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Correspondence
Pre-operative informationabout anaesthesia – is morebetter?
We were interested to read the letter
entitled �Consent for anaesthesia�(Chapman & Wolff. Anaesthesia 2002;
57: 710) as we grapple with the
problem of what and how much to
tell patients about their anaesthetic. As
a follow up to the audit of Drs
Chapman and Wolff, we asked a group
of 100 patients the same questions
before and then after surgery and
whether, in retrospect, they felt they
had received an appropriate amount of
information.
Before surgery, the patients were
asked to indicate their preference as
follows:1. I would like to be given a full and
detailed explanation of the anaesthetic,
any possible alternatives, together with
all the risks and benefits of each tech-
nique.2. I would like a simple description of
the anaesthetic together with an explan-
ation of the main risks and benefits.3. I expect that my best interests will
be followed and I would like to be
told as little as possible about the anaes-
thetic.
The postoperative questions were:1. Did you receive an appropriate
amount of information about the anaes-
thetic prior to the operation?2. If no, would you have liked less
information or more information either
written or verbal?
We also collected basic demographic
data of age, gender and occupation.
Of the 100 patients presenting for
general or urological surgery, 88 were
elective and 12 urgent. The gender ratio
was male 44, female 56, and the age
distribution is shown in Table 1. The
results of the audit are summarised in
Tables 2 and 3:
When broken down by gender, there
was little difference in the amount of
information desired or received. When
analysed by age, the majority in each
age group wanted Level 2 information
except in the over 80s who preferred
Level 3 (minimal) information. There
were more in the 40–59 age group who
wanted Level 1 than in other age
groups, but a consistent one-third in
each group between 20 and 80 years
only wanted Level 3. No trends
emerged with regard to occupational
group.
In contrast to the audit by Chapman
and Wolff, the majority of our patients
wanted Level 2 information, i.e. a
simple explanation of the procedure
and main risks and benefits (which
perhaps reflects our more elderly popu-
lation). Patients wanting Level 1 infor-
mation were in a minority regardless of
age. Nevertheless, it was gratifying that
83% of those wanting Level 1 and over
90% of those wanting partial or minimal
information were satisfied with what
they were told. At present, all our
patients get a pamphlet about coming
to theatre but not one purely dedicated
to anaesthesia, although we are planning
to introduce new ones based on the
Royal College of Anaesthetists pub-
lished booklets. However, this audit
reminds us that about a third of our
patients only want minimal information
anyway and are happy with what they
are getting. More detailed written
information probably should be offered
All correspondence should be addressed to Dr David Bogod, Editor of Anaesthesia, Anaesthesia, Ist Floor, Maternity Unit, Nottingham
City Hospital, Hucknall Road, Nottingham NG5 1PB, UK.
Letters (two copies) must be typewritten on one side of the paper only and double spaced with wide margins. In addition, please
include your letter as a Word for Windows or .rtf document on disk or alternatively submit as an e-mail attachment addressed to
[email protected]. Alternatively, a response to a previously published article or letter can be submitted online at
www.anaesthesia correspondence.com. Copy should be prepared in the usual style and format of the Correspondence section. Authors must
follow the advice about references and other matters contained in the Notice to Contributors to Anaesthesia printed at the back of the
January and July issues. Author guidelines can also be found on www.blackwellpublishing.com/journals/ana/submiss.htm. The degree and
diploma of each author must be given in a covering letter personally signed by all the authors.
Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for
revision.
Table 1 Age distribution.
Age Male Female Total
0–19 0 1 120–39 7 11 1840–59 14 21 3560–79 19 14 3380 + 4 9 13
Table 2 The desired level of information.
Level 1 (full) 18%Level 2 (partial) 47%Level 3 (minimal) 35%
Table 3 Information desired vs. information
given.
satisfied%
wanting
more%
wanting
less%
Level 1 (full) 83 6 11Level 2 (partial) 91 9 0Level 3 (minimal) 94 0 6
Anaesthesia, 2003, 58, pages 1119–1146.....................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1119
but not necessarily thrust upon all
patients. When we do introduce our
new booklets we will be auditing how
many patients actually read them! As
always, you can’t please all of the
patients all of the time.
S. El-Sayeh
N. G. Lavies
Worthing and Southlands Hospitals,
NHS Trust,
Worthing BN11 2DH, UK
Patient refusal of riskinformation and consent
We read with interest the recent article
�The information requested by patients
prior to giving consent to anaesthesia�(Moore & Pace. Anaesthesia 2003; 58:
703–7) which again demonstrates diffi-
culties in obtaining fully informed
consent for anaesthesia. The authors
question whether patients in the study
who specifically refused information
should have been forced into accepting
further relevant information and disclo-
sure about risks.
The GMC require that patients asked
to consent to treatment be given not
only the information that they want but
also that enables them to make an
informed decision about their care [1].
Discussing risk is an essential part of
informing patients about anaesthesia and
is now enshrined in the Department of
Health guidance on consent [2]. How-
ever, not all patients want to know
about risk because it frightens them [3]
and this problem is alluded to in the
Association of Anaesthetists recommen-
dations [4] that the estimated capacity of
the patient to want to know about risk
should be considered when deciding
what to explain. Can these apparently
conflicting viewpoints be resolved?
Consent derives from the principles
of autonomy, the Kantian doctrine that
the human will carries its guiding
principles within itself and elegantly
stated in law in the Schloendorff vs.
Society of New York Hospital case [5].
When patients explicitly state that they
prefer not to discuss risk issues and leave
all decisions to the doctor, and as long as
that decision to be dependent is made
freely, it is an autonomous one
and should be respected [6]. This is
consistent with the work of Skene and
Smallwood [7], which suggests modify-
ing the detail of the information given
to each patient according to their
present wishes. To address the problem
of patients whose wishes change in
retrospect, risks not disclosed along
with the reason why they were not
disclosed, should be documented [1].
Risk communication strategies with-
in the NHS are evolving as evidenced
by the recent publication: �Raising the
Standard; Information for Patients� [8]
and attempts to find and publicise
up-to-date and accurate estimates of
the risks of anaesthesia continue. But at
the centre of this process, anaesthetists
and patients need to be comfortable
about discussing how much information
and how much part in decision-making
the patient wants. Certainly, informa-
tion has to be offered in a sensitive
manner as fully as each patient wishes to
have it and in such a way that it is easily
accessible to those who do not yet
know exactly what it is they want.
However, within the concept of shared
decision-making, some clinical deci-
sions will be made by the patient alone
and this includes the decision to accept
or refuse information.
N. G. Smart
D. A. Varveris
S. Hivey
Glasgow Royal Infirmary,
Glasgow G4 OSF, UK
E-mail: [email protected]
References1 Seeking Patients’ Consent: the Ethical
Considerations. General Medical
Council, 1999.
2 Reference Guide to Consent for
Examination or Treatment. Depart-
ment of Health, 2001.
3 Smart NG, Varveris DA. Communi-
cation of Risk and Patient Satisfaction.
European Journal of Anaesthesia 2002;
19 (Suppl. 24): 10.
4 Information and Consent for
Anaesthesia. The Association of
Anaesthetists of Great Britain and
Ireland, 1999.
5 Scholendorff v Society of New York
Hospital, 1914: 211 NY 125.
6 Harrison A. Choice is a gift from the
patient to the doctor, not the other way
around. British Medical Journal 2000;
320: 874.
7 Skene L, Smallwood R. Informed
consent: Lessons from Australia. British
Medical Journal 2002; 324: 39–41.
8 Raising the Standard. Information for
Patients. The Royal College of
Anaesthetists, 2003, London.
Mortgage advice – helping youto choose your anaesthetic
I have recently seen a mortgage adviser
and, before the consultation began, was
given a leaflet about the Mortgage Code
[1]. The adviser explained to me that
there are three possible levels of advice
and that she would offer me levels one
and three only. It occurred to me that I
could usefully offer the same service to
patients about to have an anaesthetic by
substituting the word mortgage for
anaesthetic throughout a large portion
of the leaflet.
�Level One: advice and a recommen-
dation as to which mortgage is most
suitable for you. When giving advice, we
will take care to help you to select a
mortgage to fit your needs by asking for
relevant information about your circum-
stances and objectives. Our advice will
also depend on your particular require-
ments and on the market conditions at
the time.� �Level Two: information on
the different types of mortgage product
we offer so that you can make an
informed choice of which to take.� �Level
Three: information on a single mortgage
product only if we only offer one
mortgage product or if you have already
made up your mind.’ Although I think
leaflets are over-rated as we are over-
loaded with written information already,
I found it interesting that the adviser was
quite clear that she would not tell me
about every mortgage available, but only
the ones which she had chosen as being
good products. She was effectively saying
that she would use her knowledge of the
current market and our circumstances to
pick the best mortgage available.
I feel that there is a trend towards
offering Level Two advice when Level
One might be more appropriate. The
patient has to come to a decision over
minutes or hours when it has taken us
years to come to our own informed
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1120 � 2003 Blackwell Publishing Ltd
decisions. I have felt a guilty sense of
relief when a patient has chosen the
easier option for me as an anaesthetist –
guilty because my conscience doubts
the facts on which their decision was
based, despite careful explanation.
Paternalism in healthcare is out of place,
but is it wrong to offer someone what
you might like for yourself or your
relatives given similar circumstances,
and say so?
Of course, we will always meet the
Level Three patients who greet us
enthusiastically with a download about
Combined Spinal Epidurals as tech-
nique of choice for varicose veins, and
we will also occasionally resort to our
single mortgage product as we only
offer one product at that time of night.
F. Martin
Royal Cornwall Hospital,
Truro, UK
Reference1 The Mortgage Code 2nd edn. April,
1998; Reprinted January 2003 Pub-
lished by the Council of Mortgage
Lenders.
Consultation beforeanaesthesia
The authors of the article who investi-
gated the information patients requested
prior to consent (Moores & Pace.
Anaesthesia 2003; 58: 703) are to be
congratulated. As an anaesthetist and
Head of Department of Anaesthesia and
ICU in cardiovascular surgery, I share
similar preoccupations about pre-
anaesthesia information. Indeed, similar
humanitarian and medico-legal issues
seem to exist in Scotland and France.
However, our duty is somewhat facili-
tated by the legal rules issued on
December 5 1994 which is applicable
to all anaesthesia in France except
emergencies: an anaesthetic consulta-
tion is compulsory at least 2 days prior
to anaesthesia and must be held in a
dedicated office. This consultation is
complemented by an anaesthetic visit
within hours prior to anaesthesia.
Therefore, a full explanation and
anaesthetic consent are delivered during
the consultation and this allows time for
the patient to think and ask further
questions during the visit. The anaes-
thetic consent is no longer obtained �the
night before or the morning of theatre�.Of course, this consultation is a burden
for anaesthetists but after nearly 9 years
experience, this arrangement has proved
to be beneficial both for patients and
professionals.
J.-J. Lehot
Lyon, France
E-mail: [email protected]
Consent in patients withlanguage dificulties
The recent article on consent for
anaesthesia (White & Baldwin. Anaes-
thesia 2003; 58: 760–74) is very inform-
ative and timely. However, we would
like to add some comments about the
consent in patients with language diffi-
culties, an issue not covered in this
article. This matter has not got the
attention it deserves, either in the
guidelines of professional bodies [1,2]
or local trust guidelines. The matter
goes much deeper than the provision of
patient advocates. We recently carried
out a survey which showed that a large
proportion of patients (32%) attending
inner city day surgery units in and
around London spoke very little or no
English. Although 60% of these units
have interpreting services, they have no
written peri-operative information in
other languages. The interpreting ser-
vices in these hospitals are under-
resourced and often available only
between 9 and 5 on weekdays. The
already difficult situation is made worse
when the only available interpreters are
the relatives who, according to legal
experts, can’t act legally as interpreters
or patient advocates. Also, for cultural
and religious reasons, patients some-
times are not comfortable with relatives
acting as their interpreters. For example,
they may not want their relatives to be
aware of the nature of the procedure
(e.g. termination of pregnancy) or its
risks (e.g. retrograde ejaculation follow-
ing TURP). Even when interpreted
correctly, this group of patients may
not fully understand what exactly the
consent involves, reflecting the poor
knowledge of health relevant aspects in
some ethnic minority groups [3]. The
provision of peri-operative written
information in languages other than
English would go some way in addres-
sing this problem. But in view of the
possibility of courts moving towards a
reasonable patient standard of informa-
tion disclosure, more needs to be done.
S. Quadri
P. Saunders
St Bartholomew’s Hospital,
London EC1A 7BE, UK
E-mail: [email protected]
References1 Association of Anaesthetists of Great
Britain and Ireland. Information
and Consent for Anaesthesia.
http://www.aagbi/pdf/consent1.pdf.
2 Department of Health. Good Practice in
Consent Implementation Guide Consent
to Examination or Treatment. London:
Department of Health 2001.
3 David M, Borde T, Kentenich H.
Knowledge among German and
Turkish. women about specifically
female bodily functions, contraception,
preventive medical examinations and
menopause. Ethnic Health 2000; 5:
101–12.
The use of ethnicity to identifythe population at risk inpre-operative sickle cellscreening
In their recent study to determine the
ethnic mix of those patients being pre-
operatively screened for sickle cell dis-
ease in a London teaching hospital
(Pemberton et al. Anaesthesia 2002; 57:
334–7), the authors raise issues con-
cerning the operational scope of their
PAS system to record ethnicity, the
reasons for low levels of ethnicity
recording, the unsuitability of the eth-
nic categories, and the difficulties that
may be experienced in interpreting such
data. There is now an evidence base that
can be used to address some of these
matters. Moreover, a substantial pro-
gramme of work on designing and
testing candidate ethnicity questions
for antenatal sickle cell screening is
nearing completion. The investigators
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1121
report that 32% of the patients
(593 ⁄ 1879) studied have no ethnic
origin entered into the PAS system.
Surprisingly, they remark that �…ethnic
origin and religion remain non-
compulsory fields within this system�and so continue to be poorly recorded,
a conclusion which they may have felt
to be justified by the figures. In fact,
ethnic group became a mandatory data
item for all patients admitted to NHS
hospitals from 1st April 1995 [1]. In
spite of this and the long time – now
over 8 years – that the data has been
collected, only modest improvements
have been achieved in levels of com-
pleteness and very little use has been
made of these data [2]. In 2002, the
NHS Executive’s London Office set a
regional target of no more than 20% of
records uncoded in an attempt to
improve quality.
With respect to the low completion
rate of ethnicity data on the PAS
system, the investigators query whether
this is due to reluctance on the patients’
part to give this information or the
clerical staff to record it. Refusals on the
ground of an objection to the ethnic
origin question are likely to be low. In
pooled data from general practice ethnic
monitoring for 6655 patients, only 0.1%
refused to give their ethnicity [3]. In
another set of data from general practice
relating to 12 027 patients, only 0.5%
refused [4]. Of a total of 51 417 coded
hospital inpatient finished consultant
episodes recorded for NHS trusts in
the former South Thames Region that
reported refusals, only 1.8% gave eth-
nicity information as refused (range,
0.9–3.0%) [2]. Similar proportions are
reported in Government social surveys:
1% refusals for 270 156 respondents in
pooled General Household Survey data
for Britain, 1984–94 [5] and 0.9% for
pooled Labour Force Survey Data,
1989–91. Finally, in the analysis of
response to the 1989 Census Test
[6], < 0.5% of 1889 respondents
�refused in principle because of the
ethnic group question� (range: �Asian�(all groups), 0% – �Black� (all groups),
1%). Thus, consistently around only
0.1–1.8% of respondents in censuses and
surveys and ethnicity data collections
refuse to answer the ethnic question.
Administrative failure to collect the data
is likely to be the main reason. For
example, of data reported for the 338
NHS trusts admitting patients in Eng-
land in 2001–02, 11.5% of trusts
(n ¼ 39) were able to achieve usable
ethnicity coding on > 95% of all fin-
ished general and delivery episodes,
46.4% of trusts (n ¼ 157) on > 75% of
episodes, but 18.3% of trusts (n ¼ 62)
on < 40% of episodes, the figure for
England being 63.4% [7].
Attention is also drawn to the unsuit-
ability of the 1991 Census ethnic cat-
egories on the PAS system for the
purposes of risk assessment for sickle
cell screening, especially the fact that
they fail to capture the rapidly expand-
ing �mixed race� population and conceal
the Eastern Mediterranean groups. In
October 2000, NHS Trusts were noti-
fied that they would need to start
collecting ethnicity data using the
2001 Census classification from 1 April
2001 [8]. This is an improvement on
the 1991 options in that there is a
�Mixed� group broken down into
�White and Black Caribbean�, �White
and Black African�, �White and Asian�,and �Any other mixed background�.However, it still falls short of what is
needed for screening purposes. The
Mediterranean groups remain subsumed
within the �White� group and mixed
groups involving these Mediterranean
ethnicities are not distinguishable.
Moreover, there is no Arab or Middle
Eastern category. The investigators also
rightly point to the potential for errors
arising from misinterpretation of the
ethnicity recorded by those deciding
who should get screened, emphasizing
the importance of guidance and training
in this area.
A comprehensive review has been
undertaken of the literature on ethnicity
concepts and classifications for the NHS
Sickle Cell and Thalassaemia Screening
Programme and an evidence-based
question proposed for selective antena-
tal screening for sickle cell disorders
[9,10]. This question adds the options of
�Greek or Greek Cypriot�, �Turkish or
Turkish Cypriot�, and �Italian, Maltese,
or other Mediterranean� under the
�White� group and �North African,
Arab, or Iranian� under the �Other�
group, and contains an instruction to
�please tick all boxes…that apply to you�from those listed for persons of �Mixed�ethnic ⁄ family origins. It is currently
being tested – along with an
open response ethnic ⁄ family origins
question – in a formal trial in four
centres (Birmingham, Exeter, Leicester,
and London) and the results for some
4000 women interviewed at their first
antenatal booking visit will be posted on
the NHS Sickle Cell and Thalassaemia
Screening Programme’s website in
October 2003.
P. Aspinall
University of Kent
Canterbury CT2 7NF, UK
E-mail: [email protected]
References1 NHS Executive. Collection of Ethnic
Group Data for Admitted Patients, Letter
EL 94, 77. Leeds: NHS Executive
1994 (September).
2 Aspinall PJ. The mandatory collection
of data on ethnic group of inpatients:
Experience of NHS trusts in England
in the first reporting years. Public
Health 2000; 114: 254–9.
3 Sangowawa O, Bhopal R. Can we
implement ethnic monitoring in pri-
mary health care and use the data? A
feasibility study and staff attitudes in
North East England. Public Health
Medicine 2000; 2: 106–8.
4 Alves B, Kapasi R, Silvera M, Thomas
M. The primary care ethnicity project.
Evaluation Report. London: Primary
Care Ethnicity Project 2000.
5 Evandrou M. Ethnic inequalities in
health in later life. Health Statistics
Quarterly 2000; 8: 20–8.
6 Sillitoe K, White PH. Ethnic group
and the British census: The search for
the question. Journal of the Royal Statis-
tical Society Series A 1992; 155: 141–63.
7 Department of Health. HES data
quality report: data year 2001 ⁄ 02:
http://www.doh.gov.uk/hes/qual-
ity_zone/summary_dqi_01.xls. Date
last accessed, 22 July 2003.
8 NHS Information Authority, DSC
Notice, 21 ⁄ , 2000. CDS, HES &
Workforce: Ethnic data. Birmingham:
NHS. Information Authority 2000
(October).
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1122 � 2003 Blackwell Publishing Ltd
9 Aspinall PJ, Dyson SM, Anionwu EN.
The feasibility of using ethnicity as a
primary tool for antenatal selective
screening for sickle cell disorders:
pointers from the research evidence.
Social Science and Medicine 2003;
56: 285–97.
10 Aspinall PJ. Synthesis of the Literature.
In: Aspinall, PJ, Dyson, SM, eds.
Secondary, Review of Existing Informa-
tion in relation to the Ethnic Question.
London: 2002, NHS Sickle Cell &
Thalassaemia Screening Programme,
3–132 (http://www-phm.umds.ac.uk/
haemscreening Date last accessed,
22 July 2003).
Sleep quality followinggeneral anaesthesia
We write to report a pilot study
undertaken in our institution using
Actigraphs to observe sleep during the
postoperative period. The Actigraph is a
wristwatch-sized device that responds
to movement of its wearer, the record-
ings from which are used to differentiate
between sleep and wake periods. They
have been used to assess objectively the
length and quality of sleep in both
normal subjects and patients with sleep
disorders, and their use for evaluating
within-subject treatment effects has
been established [1]. A small number
of studies have used EEG recording for
assessment of sleep in postoperative
patients [2,3]. Unlike EEG recordings,
Actigraphs do not show a �first night
effect�, because the device is unobtru-
sive, making them a potentially more
useful tool for patients in the peri-
operative period.
After approval by the local hospital
ethical committee, 11 female patients
scheduled to undergo elective breast
surgery were recruited. Patients were
admitted the day before surgery,
interviewed, and written informed con-
sent was obtained. Use of the Gaeh-
wiler actigraph (Gaehwiler Electronics,
Hombrechtikon, Switzerland) was
explained and the patient completed a
sleep questionnaire. The Actigraph was
attached to the wrist and remained in
place until 48 h after surgery. It was
removed only for the duration of sur-
gery, and to bath or shower, being
reattached immediately after.
A personal computer (PC) holding
the appropriate software was used to
activate the devices. At the end of the
study period, they were re interfaced
and movement information down loa-
ded. The software computed periods of
wakefulness and sleep, duration of
sleep, movement during sleep, and
time in the 24 h at which sleep
occurred. The periods of sleep were
divided into epochs of one minute for
further analysis. Quality of sleep is
judged in terms of two indices: the
movement index and the frequency of
movement onsets. The movement
index is the number of epochs with
movement occurring during the sleep
period as a percentage of the total
number of epochs asleep. The fre-
quency of movement onsets is the
number of epochs with movement that
follow an epoch with no movement as
a percentage of the total number of
epochs asleep. In the postoperative
period, the patients were interviewed
and a sleep questionnaire completed
for each postoperative night. The
patients all received patient-controlled
analgesia of intravenous boluses of
morphine 1 mg, with a 5-min lockout
time and no 4 h limit, from a Graseby
PCA machine.
We obtained Actigraph data sets for
the 3-day period for all 11 patients.
These were analysed statistically using
Friedmans two-way ANOVA Chi Square
test. We found that movement index,
frequency of movement onsets and
duration of sleep did not differ signifi-
cantly between the pre-operative and
postoperative nights (Table 4). Sleep
duration was short on all nights, bet-
ween 5 and 6 h, but was longest on
the first postoperative night. Time of
waking differed significantly across the
three nights, with waking on the first
night after surgery being earlier (Chi
Square ¼ 6.05, d.f. ¼ 2, p < 0.05); time
of going to sleep did not differ sig-
nificantly across the three nights.
Self reported awakenings were few.
However, there was a significant differ-
ence between the first two nights and
the third night. Patients reported more
awakenings on the first two nights,
between which there was no significant
difference, and fewer on the third night.
Patients reported significantly more
awakenings on each night in hospital
than normally at home. We have shown
that the mean sleep duration in our study
was short on each night. Patients went
to sleep late, and woke early. On the first
postoperative night, there was a trend
towards going to sleep earlier, but
wakening was still between 5 and 6 am
in the morning. The quality of sleep as
judged by the movement index and
frequency of movement onsets did not
differ across the three nights. The indices
recorded are comparable to those recor-
ded in other studies for normal subjects
sleeping at home. Movement onsets of
5% in females aged between 35 and 49
and 7% in women over 50 years have
been recorded [4,5]. This suggests that
the patients maintained their sleep qual-
ity at levels similar to those that control
subjects might obtain, and that this did
not change across the operative period.
We have studied female patients under-
going breast surgery. Sleep quality after
Table 4 Means (SD) of sleep length, movement index, and frequency of movement onsets, and
medians (range) of time starting sleep and waking. Sleep time and movement variables assessed by
actigraph; number of awakenings assessment by self-report.
Pre-operative 24 h Postoperative 48 h Postoperative
Sleep length (min) 334.8 (80.2) 385.5 (129.4) 353.5 (120.8)Movement index(%)
10.1 (3.5) 9.8 (6.9) 9.9 (6.3)
Movement onset(%)
6.1 (2.1) 5.1 (3.2) 4.9 (2.2)
Time startingsleep h
24.00 (22 : 25–01 : 14) 22.47 (19 : 12–02 : 42) 23 : 35 (21 : 47–02 : 54)
Time waking 05 : 34 (03 : 54–07 : 51) 05 : 19 (02 : 14–06 : 35) 05 : 56 (03 : 36–07 : 10)Number ofawakenings
2.8 (1.7) 3.8 (2.1) 1.4 (0.9)
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1123
more major surgery may be very differ-
ent. Studies of nocturnal hypoxaemia
following surgery have suggested that
the periods of de-saturation are maximal
on the second postoperative night [6].
The Actigraph technique would be a
useful tool for studying such patients.
In conclusion, our study suggests that
patients in hospital for elective surgery
sleep less than at home, have more
reported awakenings during the night,
but maintain their quality of the sleep
close to that which they might enjoy
at home. These data indicate the use-
fulness of the Actigraph for measur-
ing sleep quality in the peri-operative
period.
L. M. Bromley
B. Brandner
The Middlesex Hospital,
London, UK
M. Blagrove
University of Wales,
Swansea, UK
References1 Chambers MJ. Actigraphy and
Insomnia: a closer look Part 1. Sleep
1994; 17: 405–8.
2 Rosenberg-Adamsen S, Kehlet H,
Dodds C, Rosenberg J. Post-operative
sleep disturbances: mechanisms and
clinical implications. British Journal of
Anaesthesia 1996; 76: 552–9.
3 Edell-Gustafsson U, Hetta JE, Aren
CB. Sleep and Quality of life assess-
ment in patients undergoing coronary
artery bypass grafting. Journal of
Advanced Nursing 1999; 29: 1213–20.
4 Blagrove M, Owens DS, MacDonald I,
Syntik N, Tucker P, Folkard S. Time
of day effects in, and relationship
between, sleep quality and movement.
Journal of Sleep Research 1998; 7:
233–9.
5 Horne JA, Pankhurst FL, Reyner LA,
Hume K, Diamond ID. A Field study
of sleep disturbances. effects of aircraft
noise and other factors of 5742 nights
of actimetrically monitored sleep in a
large subject sample. Sleep 1994; 17:
146–59.
6 Rosenberg J, Ullstad T, Rasmussen J,
Hjorne FP, Poulsen NJ, Goldman
MD. Time course of postoperative
hypoxaemia. European Journal of Surgery
1994; 160: 137–43
An interesting case ofpostoperative stridor
I recently anaesthetised a 52-year-old
lady for an elective hysteroscopy. She
had C1 esterase inhibitor deficiency, also
known as hereditary angioedema. Dur-
ing the pre-operative assessment, it was
established that she suffered frequent
bouts of oedema, often affecting the
upper respiratory tract. One episode had
required the administration of C1 inhib-
itor concentrate. She took regular Dan-
azol (200 mg twice daily), a recognised
prophylactic and she was to receive 1500
IU of C1 inhibitor concentrate 12 h
prior to surgery. She was otherwise fit
with no other medical history, drug
history or allergies. She had a Mallampati
score of I with good mouth opening.
Intubation, I felt, would be the safest
option as peri-operative laryngeal
oedema was a definite possibility. I also
planned to release as little histamine as
possible, choosing propofol as my induc-
tion agent and vecuronium for neuro-
muscular blockade. On laryngoscopy
there was a good view of the larynx
and was intubated easily with an 8-mm
cuffed tracheal tube. Oxygen, nitrous
oxide and isoflurane maintained the
anaesthetic and the 20 min procedure
passed without incident, although a short
delay occurred waiting for the vecuro-
nium to wear-off. She received neostig-
mine and glycopyrolonium reversal and
was extubated shortly afterwards.
On arrival in recovery, she appeared
comfortable with no evidence of respir-
atory distress, no stridor, with a saturation
of 98% on oxygen 4 l. The recovery staff
members were instructed to keep close
observation and were informed of the
seriousness of her inherited condition.
Within 10 min, I was called back to
recovery urgently, where the patient had
developed obvious stridor with an oxy-
gen saturation of 84%. Her condition,
fortunately, settled with nebulised epi-
nephrine (5 ml of 1 in 1000 ¼ 5 mg) and
intravenous chlorphenamine 20 mg. She
also received intravenous hydrocortisone
100 mg. She was feeling �back to nor-
mal� within the hour with an oxygen
saturation of 99% and no evidence of
respiratory distress. On discharge to the
gynaecology ward, the nursing staff
members were instructed to keep close,
regular observations overnight and to call
an anaesthetist at the first sign of any
respiratory distress. The patient was dis-
charged from hospital the following day.
C1 esterase inhibitor deficiency pre-
sents with recurrent bouts of cutaneous
and mucus membrane oedema in any
part of the body. It is an autosomal
dominant disorder with a prevalence
of 1 in 50 000. In the presence of C1
inhibitor deficiency, the classical com-
plement pathway can be inappropriately
activated, resulting in the stimulation
of anaphylactoid and vasoactive sub-
stances. Attacks can occur as regularly as
weekly and can be precipitated by
minor trauma, infection and possibly
emotional stress as well as a variety of
exogenous compounds. Danazol and
other attenuated androgens have been
shown to reduce both the severity and
frequency of symptoms by stimulating
the hepatic production of C1 inhibitor.
Tranexamic acid appears to inhibit C1
and plasmin directly.
For those undergoing a surgical pro-
cedure, prophylaxis with an infusion of
C1 inhibitor concentrate should be
given 6–12 h before surgery (as in the
above case) and an infusion of concen-
trate is also recommended in a severe
acute attack.
I am quite sure this patient developed
laryngeal oedema as a consequence of
the trauma of intubation ⁄ extubation.
The real question is this: how should
one manage such a patient’s airway for a
relatively minor surgical procedure?
Other choices include insertion of
a laryngeal mask airway or even holding
a facemask. Would either of these be a
safer option? They would avoid the
mucosal trauma of extubation but not
the potentially disastrous consequences
of laryngeal ⁄ pharyngeal oedema on the
operating table.
P. Hynam
Musgrove Park Hospital,
Taunton, UK
E-mail: [email protected]
References1 Fay A, Abinun M. Current manage-
ment of hereditary angio-oedema
(C1 esterase inhibitor deficiency).
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1124 � 2003 Blackwell Publishing Ltd
Journal of Clinical Pathology 2002;
55: 266.
2 Visentin DE, Yang WH, Karsh J. C1
esterase inhibitor transfusions in
patients with hereditary angioedema.
Annals of Allergy Asthma and
Immunolology 1998; 80: 457–61.
Cannabis abuse and anaesthesia
Patients were asked to complete a form
asking about their recreational drug use
in the last 6 months and also to specify
frequency of illicit drug use. All patients
completed a form (n ¼ 57) of whom
nine patients reported cannabis use in
the last 6 months and eight were regular
users. This is a prevalence of 14% in this
day surgical population.
Government figures confirm that
recreational cannabis use has increased
significantly in the last 10 years [1] and
therefore the likelihood of a patient
presenting for anaesthesia who is a
regular or occasional user has risen. As
cannabis is very slowly eliminated, the
tissue half-life is approximately 7 days
[2], it may be present in the body for
many weeks after abstinence and con-
tinue to react cumulatively with sedat-
ive agents [3].
Cannabis smoking is also associated
with upper airway irritability as well as
the impairment in lung function that is
seen in tobacco smokers. It has been
estimated that 3–4 cannabis cigarettes
smoked daily are equivalent to 20
tobacco cigarettes in terms of causing
acute and chronic bronchitis and dam-
age to the bronchial tissue [4]. There
have also been reports of acute upper
airway oedema and obstruction in can-
nabis smokers undergoing general
anaesthesia [5]. Concern has been
expressed in the literature about
adverse psychiatric and autonomic reac-
tions in patients who are regular canna-
bis users receiving anaesthetic agents [3].
In light of the increasing use of
cannabis in the general population, we
would recommend that questioning
about illicit drug use becomes a part of
routine preanaesthetic assessment. In
addition, anaesthetists should have a
high index of suspicion of illicit drug
use in patients who prove unusually
difficult to �settle� with no other easily
identifiable cause as unrecognised can-
nabis users can present particular prob-
lems in anaesthetic management.
P. M. Mills
N. Penfold
West Suffolk Hospital,
Bury St Edmunds, UK
E-mail: [email protected]
References1 Parliamentary Office. of science and
Technology (1996). Common illegal
drugs and their effects-Cannabis,
Ecstasy, Amphetamines and LSD.
House of Commons 1996.
2 Busto U, Bendayan R, Sellers EM.
Clinical pharmacokinetics of non-
opiate abused drugs. Clinical Pharmaco-
kinetics 1989; 16: 1–26.
3 Ashton CH. Adverse effects of cannabis
and cannaboids. British Journal of
Anaesthesia 1999; 83: 637–49.
4 Wu TC, Tashkin DP, Djahed B, Rose
JE. Pulmonary hazards of smoking
marijuana as compared with tobacco.
New England Journal of Medicine 1988;
318: 347–51.
5 Mallat AM, Robertson J, Broch-Utne
JG. Perioperative marijuana inhalation –
an airway concern. Canadian Journal of
Anaesthesia 1996; 43: 691–3.
Double labelling syringes
There has been anxiety over an
increased risk of drug error whilst the
changeover to the new �International�standardised syringe labelling system is
made [1]. Indeed, the Royal College of
Anaesthetists and the Association of
Anaesthetists suggests heightened vigil-
ance during the period of transition. It
has been suggested that double-labelling
syringes may reduce errors from
so-called �drug swap� [2]. I describe a
simple experiment conducted in our
department to explore this concept.
Labels for 21 different drugs were
arbitrarily chosen to label 42 syringes.
For each drug, one syringe was labelled
with a single label wrapped around the
base and another with one around the
base in the same fashion plus a second
label applied on the opposite side from
the graduated markings in line with the
long axis of the syringe (Fig. 1). A
mixture of new �international� labels and
Medilabel style (currently in use in our
department) were used. Anaesthetists and
ODAs from the department were then
asked to take part in the experiment and
were given the following instructions:
They would be presented with a
sample of syringes (tipped onto a flat
surface randomly from a bag), each was
labelled, some with the �new� style labels
and others with those in current use.
Syringes were labelled appropriately
for their size, i.e. vecuronium in a 5-ml,
thiopental in a 20-ml, etc. Any local
anaesthetic would be in a 20-ml syringe.
They would be asked to pick out
sequentially, drugs from the sample as
dictated from a list.
Syringes could be handled but not
sorted into sizes or colours.
The first syringe found with the
name of the drug asked for should be
picked out and placed to the side. Once
the syringe was released from the hand
they could not change their mind and
the name of the next drug to be found
was called out.
The exercise was to be timed but
accuracy was the most important aspect.
They were not told the following:
Every drug appeared twice
That they would be asked to locate
every drug in the sample
That half the syringes were double
labelled.
The sample consisted of 16 2.5 ml,
eight 5 ml, 12 10 ml and six 20 ml
syringes; 18 syringes had new style labels
(Fig. 2). A limited selection of new
labels was available, a random sample of
these were used.
A total of 34 people took part in the
test: 11 consultants, five non-consultant
career grades, four specialist registrars,
five senior house officers (SHO) and
nine operating department assistants
(ODA). Times to complete the task
ranged from 81 to 457 s. There were
three mistakes, all by different people:
two by ODAs (both involving muscle
relaxants) and one by an SHO (mis-
taking ephedrine for epinephrine). In
all, 714 syringes were picked out (34
people each selecting out 21). Of the
syringes selected, 417 were double
labelled; this accounts for 58.4%
(CI 54.8–62) of the sample.
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1125
Figure 1 There were 2 syringes for each drug. One double labelled, the other with one label.
Figure 2 42 Syringes were randomly tipped onto a flat surface for the experiment.
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1126 � 2003 Blackwell Publishing Ltd
Although syringes were not replaced,
so long as the candidate had previously
identified the correct drugs, the chance
of selecting a double-labelled syringe
correctly remained 0.5. The results
indicate that there is a tendency for
double labelled syringes to be selected
more often than single labelled ones.
Although this result is statistically signi-
ficant (the 95% confidence interval does
not cross 50%, the point at which there
is no tendency, i.e. double are selected
as often as single labelled syringes), the
effect is modest.
Various methods have been suggested
to improve recognition of a syringe
label and minimise the risk of drug error
[2–4]. Various cues are involved at
various stages in selecting the correct
syringe from a drug tray. The size of the
syringe is one of the initial cues and
remains an important source of �drug
swap� error [5,6]. Reading and register-
ing the drug name on the label is the
final essential stage of this process.
Colour coded labels are an aid to the
process, although their impact on redu-
cing drug error is debatable [7].
Standardisation of syringe labelling by
the introduction of the new �Interna-
tional System� is upon us and will
hopefully help to reduce risks of drug
errors in the future. However, recent
concerns over how to make the trans-
ition from one system to the other are
understandable [8,9].
The importance of syringe size as a
primary cue remains with an unfamiliar
colour coding system. However, any-
thing that minimises the tendency to
rely on colour as a cue for the correct
drug but maximises the chances of
reading and registering the name of the
drug on the label should help to reduce
the tendency for �drug swap� error. This
experiment indicates that double-label-
ling syringes in the way described makes
syringes more readily identifiable from a
pile. Whether it would reduce �drug
swap� error is uncertain. Common sense
would say that such a simple interven-
tion is an aid to heightening vigilance
during the period of transition.
B. Phypers
Royal Hampshire County Hospital,
Winchester SO22 5DG, UK
E-mail: [email protected]
References1 Christie IW, Hill MR. Standardized
colour coding for syringe drug labels: a
national survey. Anaesthesia 2002; 57:
793–8.
2 Suriani RJ. Double labelling of syringes
to prevent �drug swaps�. Anaestheisa and
Analgesia 1993; 76: 665.
3 Latson TW. Labelling of syringes to
prevent �drug swaps�. Anesthesia and
Analgesia 1992; 75: 306–7.
4 Merry AF, Webster CS, Mathew DJ.
A new, safety-oriented, integrated
drug administration and automated
anesthesia record system. Anesthesia
and Analgesia 2001; 93: 385–90.
5 Jayasuriya JP. Syringe drug labels.
Anaesthesia 2000; 55: 201–2.
6 Webb RK, Currie M. Morgan CA et al.
The Australian incident monitoring
study: the �wrong drug� problem in
anaesthesia: an analysis of 2000 incident
reports. Anaesthesia and Intensive Care
1993; 21: 596–601.
7 Fasting S, Gisvold SE. Adverse drug
errors in anesthesia, and the impact of
coloured syringe labels. Canadian
Journal of Anaesthesia 2000; 47:
1060–7.
8 Souter A. Syringe labelling in critical
care areas. Anaesthesia 2003; 58: 713.
9 Frerk C, Webster R. Labels. Anaesthesia
News 2003; 192: 5.
Paediatric central venouscatheter insertion
In September 2002, the National Insti-
tute for Clinical Excellence (NICE)
report on the use of ultrasound locating
devices for placing central venous cath-
eters recommended the use of such
devices in both adult and paediatric
practise [1]. This has generated much
discussion within the profession (and
some terrible puns) and continues to be
an area of controversy [2,3]. We have
analysed the immediate complications
of central venous catheter (CVC) place-
ment in a paediatric cardiothoracic
surgery centre.
Information was gathered from 43
consecutive children undergoing CVC
insertion by anaesthetists either in
theatre (36) or the cardiac catheterisa-
tion suite (7) between October 2002
and January 2003. The information
collected included age, weight, diagno-
sis, the site and type of central venous
catheter and number of attempts made.
The grade of the operator and the use of
an ultrasound-locating device were
documented as well as a history of
previous CVC placement. Immediate
complications were defined as inability
to cannulate the vessel, inability to pass
a wire (in instances where a Seldinger
technique was used), arterial puncture
and cannulation, abandonment of pro-
cedure and any other complications
(such as pneumothorax).
A total of 71 CVCs were inserted into
�central� veins in our 43 children, aged
1 day to 12 years (median 14 months)
and weighing 1.3–38 kg (median
10.0 kg). Fifty-four CVCs were inserted
by consultants and 17 by specialist reg-
istrars. The sites of insertion was: right
internal jugular – 41; left internal jugu-
lar – 7; right femoral – 13, left femoral –
7, subclavian (left or right) – 3. The
overall rate of one or more complications
was 17 ⁄ 71 (24%). In 13 cases, the
operator was unable to cannulate a vessel,
in six cases, a wire could not be passed,
there was arterial puncture in five cases
and nine procedures were abandoned.
No arterial cannulation, pneumothorax
or any other adverse outcome related to
CVC placement occurred in this study.
Unexpectedly, there was a significantly
higher complication rate of 37.5% in the
12–48 months age group than in infants,
where 19% of insertions had one or more
complications. This phenomenon may
be partly explained by the fact that these
older patients frequently presented for
second stage or revision procedures
making repeat CVC insertion more
difficult. In support of this theory, we
found that complications occurred in just
13% of children who had no previous
central access, compared with 33% who
had previous access at a different site and
43% who had previous access at the same
site. Left internal jugular line insertion
had a complication rate of 43% (n ¼ 14)
compared to 20% of right internal jugular
lines, which is probably due to both
experience and the right-handedness of
most operators.
Ultrasound guidance was used in 11
insertions with complications occurring
in 4 of these (36%). At the time of the
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1127
study, ultrasound guidance was used as a
rescue rather than a routine technique
by most operators and further research is
warranted to determine the effect of the
widespread use of ultrasound devices on
complication rates. From this study, it
can be clearly seen that central venous
catheter insertion in paediatric cardio-
thoracic surgical patients can be difficult
and has a high rate of immediate
complications, even amongst experi-
enced operators. The overall immediate
complication rate of 24% is similar to
the placement-related complication rate
of 22% in a large previous study by
Casado-Flores and colleagues in a pae-
diatric intensive care unit [4]. In par-
ticular, insertion of CVCs into left
internal jugular veins or insertion in
patients who had previous central
venous access carries an increased risk.
In our view, ultrasound guidance devi-
ces may be especially useful in these
particular subgroups of patients.
C. R. Carey
R. Stenz
Royal Brompton Hospital,
London, UK
E-mail: [email protected]
References1 National Institute for Clinical Excel-
lence. September 2002. Guidance on the
Use of Ultrasound Locating Devices for
Placing Central Venous Catheters. Tech-
nology Appraisal Guidance No. 49.
2 Scott DHT. It’s NICE to see in the
dark. British Journal of Anaesthesia 2003;
90: 269–72.
3 White SM. Not NICE advice.
Anaesthesia 2003; 58: 295–6.
4 Casado-Flores J, Barja J, Martino R
et al. Complications of central venous
catheterisation in critically ill children.
Paediatric Critical Care Medicine 2001; 2:
57–62.
Medico legal awarenessregarding unlicensed drugadministration
Anaesthesia is unique amongst medical
specialities in requiring a high level of
performance from all practitioners, even
the most junior. One of the methods
used by the anaesthetists to improve the
quality of their technique is to extend
their use of drugs, either by using them
outside their licensed indications, or to
administer a mixture of drugs (Table 5),
which is unlicensed if not specified in
the data sheet [1]. Medico-legal con-
cerns in anaesthetics have been a hot
topic and it is of interest to know how
overseas anaesthetists think about it.
Therefore, we report the preliminary
results of a questionnaire survey, which
investigated the degree of awareness of
Egyptian anaesthetists about the medi-
co-legal aspect concerning unlicensed
drug administration, and compare it
with the experience of British anaes-
thetists. Because of the similarity of
medical practices in the Southern Medi-
terranean region, Egypt has been selec-
ted to represent the anaesthetists from
this area, while the UK has been chosen
to represent European practice.
This pilot study assesses the problem
and discusses the changes that could be
recommended to protect patients and
guide anaesthetists, not only in Europe,
but also all over the world. Three
hundred and forty-five consultant anaes-
thetists from both countries (200 British
vs. 145 Egyptians) were asked to com-
plete a postal survey anonymously
(Appendix 1). The anaesthetists from
both countries were selected at random
from the Medical Tele-Fax: Guide List
[2,3]. Working alphabetically down the
list, each person on the list had a 50%
chance of being included in the study.
This process was stopped when the
predetermined number was reached.
The figure chosen for the number of
anaesthetists was thought to be a good
representation of the consultant body in
both countries, but was a compromise
between our estimate for the number to
prove the hypothesis and being realistic
about the budget allocation and the time
limit to finish the study.
It was apparent that British anaes-
thetists (100%) were more aware than
Egyptian anaesthetists (13%) of the
problem under investigation and do
give their patients unlicensed drugs but
on a clinical basis.
We appreciate that the survey was
simple and might be criticised for being
unsystematic with a small sample size.
We are also aware that the apparent
difference between UK and Egyptian
anaesthetists’ responses could easily be
explained by cultural differences and not
due to any real difference in knowledge.
However, we have shown a difference
in approach to the problem suggesting a
need for international collaboration
between the European Association of
Anaesthetists and those in the develop-
ing countries. The Royal College of
Anaesthetists, the British Medical
Association (BMA) and the General
Medical Council (GMC) should also
seek a role in this area and give periodic
written guidance on what should be
considered �reasonable� drug practice for
anaesthetists. These guidelines could be
exchanged internationally to widen the
scope of the anaesthetists and increase
their information background.
E. A. Elrazek
St. Mary’s Hospital,
Newport PO30 5GT, UK
E-mail: [email protected]
References1 Mann Rd. Unlicensed Medicines and the
Use of Drugs in Unlicensed Indications.
Table 5 A list of some of the drugs that are regularly used by anaesthetists outside the licensed
indications.
Adults Children
Epidural opioids Intravenous dopamineSpinal lidocaine and opioids Intravenous dobutamineEpidural epinephrine Ketorolac (if < 16 years)Epidural depo-medrone Diclofenac (postoperative analgesia)Clonidine – pain relief (neuroaxial ⁄ parentral) Oral midazolamDexamethasone (antiemesis) Clonidine
DexamethasonePropofol (< 2 years)Almost everything for the neonate
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1128 � 2003 Blackwell Publishing Ltd
In: Goldberg A, Dodds-Smith, ed.
Pharmaceutical, Medicine and the Law,
1st edn. London: 1991, Royal College
of Physicians, 103–10.
2 Medical Tele-Fax. Guide List.
Thomas communications (UK) Ltd,
Portsmouth, 1997.
3 Medical Tele-Fax. Guide List. Egypt
telecommunication group, Cairo,
1999.
Appendix 1: A detailedquestionnaire sent to allanaesthetists involved in thissurvey
Q1. Are you aware about the Medi-
cines Act, which regulates the activities
of pharmaceutical companies and others
involved with the supply of the medi-
cines in your country?
Yes No
Q2. Do you usually give your patient
unlicensed medicine?
Yes No (If yes, please mention
an example)
Q3. Are you willing to give your
patient unlicensed medicine on your
responsibility?
Yes No (If yes, please explain)
Q4. Are you aware of the medico
legal implications of giving unlicensed
medicine?
Yes No
Q5. Are you aware about any compli-
cations that might have happened to
one of your patients because of giving
an unlicensed medicine?
Yes No (If yes, please men-
tion details).
Nasotracheal intubation forhead and neck surgery
According to the authors of this review
(Hall & Shutt. Anaesthesia 2003; 58:
249–56) a base of skull fracture, actual
or suspected, is an absolute contraindi-
cation to nasotracheal intubation. They
cite one reference when there is some
controversy [1–4]. Only three instances
of intracranial (anterior cranial fossa)
tracheal tube [1,5], and one of naso-
pharyngeal tube [6], misplacement have
been described. There have been more
cases with nasogastric tubes. Is the
number so low because it is not done
or is done correctly? As Goodisson,
Shaw and Snape [1] rightly point out,
for a tube to penetrate the cribriform
plate or frontal bone, it has to follow an
unconventional pathway. Clearly this
cannot happen if the tube is always
inserted in line with the hard palate
along the floor of the nose. They
concede that a correctly introduced
tube might risk entering the middle
cranial fossa if there is a compound
sphenoid body fracture; it has happened
to nasogastric tubes. However, to me,
the point of a curved tube entering the
nasopharynx abuts against the arch of
the atlas region. There seems general
agreement that each patient should be
treated individually according to clinical
and X-ray findings [1–3]. In the acute
situation, perhaps with less experienced
personnel, oral intubation can protect
the airway and breathing [1]. Electiv-
ely, where the jaws need to be wired
in occlusion, some authorities [1–3]
believe that nasotracheal intubation
can be performed routinely and safely,
whether awake topical local anaesthesia
with or without fibreoptic assistance or
rapid sequence technique with pre-
oxygenation and cricoid pressure, but
others are extremely reluctant to con-
sider it [1,2]. Several studies, in patients
with base of skull fractures, did not
show complications differed between
nasal and oral intubation [1].
Similarly, Hall and Schutt say
�patients with advanced upper airway
obstruction having difficulty maintain-
ing their airway are unsafe for any form
of awake intubation and require trach-
eostomy under local anaesthesia or
careful inhalational induction of anaes-
thesia�, but again give only one refer-
ence [7]. It is a wide field, including
areas of debate, and the cited editorial
[7] actually queried awake fibreoptic
intubation as �the method of choice in
obstructing laryngeal tumours�, which
are by no means typical of the whole.
The evidence they [7] offered against
topical anaesthesia, one unusual case
and one remote research paper, hardly
justify absolute avoidance. In fact,
Mason and Fielder [8] later admitted
that �there is no universal recipe for the
obstructed airway, it is difficult to
compare patients on paper, and anaes-
thetists will continue to argue about the
best way to achieve safe anaesthesia in
any particular circumstances�.Topical anaesthesia for fibreoptic
intubation, and for awake laryngo-
scopy ⁄ intubation, differ greatly. In the
former, it impacts on the glottis as a
sudden liquid jet (with too little applied
force the fluid dribbles out and misses
the target causing poor anaesthesia)
and reactions of varying degree are
observed. The latter, in contrast, invol-
ves the gradual spraying of the posterior
tongue, epiglottis, pyriform fossae and
glottis. After spraying only the posterior
tongue and anterior epiglottis, it may be
apparent that the glottis cannot be
visualised because of the pathology, or
inadequate cooperation, relaxation, or
mouth opening. Nebulisation of 4%
lidocaine can aid either approach. Text-
books [9,10], over the years [11], con-
sider awake laryngoscopy under topical
laryngeal block as a safe choice for
severe cases of upper airway pathology.
It retains spontaneous breathing and
helps the anaesthetist decide between
awake intubation, inhalational anaes-
thesia and awake tracheostomy [10]. In
137 awake patients with a wide range of
conditions, intubation was not achieved
in three cases (gunshot injury to
mandible ⁄ tongue, large friable pyriform
fossa tumour, and combined dental ⁄bilateral parapharyngeal abscesses with
trismus) and awake tracheostomy done.
The technique was blind nasal intuba-
tion in 68, oral unlighted stylet intuba-
tion [12] 18, fibreoptic nasal intubation
25, and laryngoscopic intubation 23;
60 had advanced cancer of the larynx.
Before inhalational induction, some
patients with laryngeal pathology exhi-
bit large excursions of the reservoir bag
but completely obstruct as anaesthesia
deepens despite measures to prevent it.
Other patients with much smaller bag
movements retain them through to
intubation. Also uncertain until after
induction is the ability to see behind the
epiglottis and view the glottis. It pays to
preoxygenate at length and induce on
100% oxygen. In doubtful cases, I ask
the surgeon to inject local anaesthesia,
including intratracheal for tracheo-
stomy. I have not seen this provoke
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1129
laryngospasm but it, and obstruction, do
occur with general anaesthesia. I try
using the laryngoscope to open the
airway, or attempt intubation (with
tube or Magill forceps or stylet or
bougie), or spray [9] the piriform fossae
and glottis. They mostly resolve as
anaesthesia lightens, or local anaesthesia
takes effect, or intubation is possible.
Obstructed airway management is a
career long apprenticeship. For every
case the least risky option is chosen
according to the assessed severity.
Things can go wrong with every
method, it is not necessarily its fault,
and the situation can usually be saved as
the following examples show.
ENT surgeons were reluctant to
attempt awake tracheostomy on a patient
in marked respiratory distress from a stab
injury to neck (zones I ⁄ II), because of
the swelling. During fibrescope intro-
duction, the patient obstructed, stopped
breathing, and lost consciousness. Trach-
eostomy was begun simultaneously with
laryngoscopy, which revealed only the
top of a grossly oedematous epiglottis
filling the distal pharynx. Blind nasal
intubation succeeded and the tracheo-
stomy was completed unhurriedly.
A 50-year-old female betel nut
chewer came with severe respiratory
obstruction months after undergoing
partial mandibulectomy, free radial graft,
neck dissection, tracheostomy, and
resection of a malignant ulcer of the
cheek. She had no jaw movement and
blocked nasal passages. Helium ⁄ oxygen
was given by mask and awake tracheos-
tomy begun through the scar. The
surgeon opened �the trachea�, removed
some tumour, and inserted a tube but
ventilation was impossible and the cap-
nograph trace was flat. As he was unable
to define the trachea, the oxygen satura-
tion fell and the patient became uncons-
cious and apnoeic. Oral unlighted stylet
intubation [12] (5.0 mm cuffed) was
successful, the trachea defined, and the
patient recovered.
A 70-year-old male came for dental
clearance preparatory to radiotherapy
for cancer of the larynx. After inhala-
tional induction, laryngoscopy could
not display the glottis and blind nasal
intubation failed. It became increasingly
difficult to keep a patent airway. A
transtracheal venous cannula obstructed
with blood after several minutes. As the
pulse rate fell, oral unlighted stylet
intubation [12] succeeded.
The CAT scan on a 26-year-old
female complaining of sore throat,
showed a large mass extending from the
left side of the nasopharynx to near the
vallecula. In the mouth, tumour could be
seen extending partway across the soft
palate. To assess grade of glottic view,
awake laryngoscopy was begun, but after
five separate puffs of aerosol lidocaine
onto the posterior tongue and adjacent
soft palate, the patient became distressed,
then obstructed, stopped breathing, and
the pupils dilated. Blind nasal intubation
was quickly done. Under anaesthesia
laryngoscopy was grade 1.
R. Williamson
Nelson R Mandela School of
Medicine, Congella 4013,
South Africa
E-mail: [email protected]
References1 Goodisson DW, Shaw GM, Snape L.
Intracranial intubation in patients with
maxillofacial injuries associated with
base of skull fractures. Journal of Trauma
2001; 50: 363–6.
2 Zymslowski WP, Maloney PL.
Nasotracheal intubation in the pres-
ence of facial fractures. Journal of the
American Medical Association 1989; 262:
1327–8.
3 Schultz RC. Nasotracheal intubation
in the presence of facial fractures.
Plastic and Reconstructive Surgery 1990;
86: 1046.
4 Williamson R. Blind nasotracheal
intubation. Anaesthesia and Intensive
Care 1998; 26: 331–2.
5 Taylor TH, Major E. Hazards
and Complications of Anesthesia.
New York: Churchill Livingstone
1987, 340–1.
6 Muzzi DA, Losasso TJ, Cucchiara RF.
Complication from a nasopharyngeal
airway in a patient with a basilar
skull fracture. Anesthesiology 1991;
74: 366–8.
7 Mason RA, Fielder CP. The
obstructed airway in head and
neck surgery. Anaesthesia 1999; 54:
625–8.
8 Hawkins TJ. The obstructed airway.
Anaesthesia 1999; 54: 1114.
9 Morrison JD, Mirakhur RK, Craig
HJL. The Larynx. In: Anaesthesia for
Eye, Ear, Nose and Throat Surgery. 2nd
edn. Edinburgh: Churchill Living-
stone 1985, 21–50.
10 Donlon Jr. JV. Anesthesia for Eye,
Ear, Nose, and Throat Surgery.
In: Miller, RD, ed. Anesthesia.
New York. Churchill Livingstone
1981, 1265–321.
11 Donlon Jr. JV. Anesthesia for Eye,
Ear, Nose and Throat Surgery. In:
Miller, RD, ed. Anesthesia, 5th edn.
Philadelphia: Churchill Livingstone
2000, 2173–98.
12 Williamson R. Unlighted stylet
tracheal intubation. Anesthesia and
Analgesia 2001; 92: 1355–6.
A replyWe welcome Dr Williamson’s adden-
dum in response to our review. He
makes comments in respect of the
intubation of patients with a base of
skull fracture, the skill of awake intuba-
tion, the career long apprenticeship in
the management of patients with com-
promised airways, and gives examples
from his own clinical experience. We
would agree that contraindications to
nasotracheal intubation, which would
be absolute contraindications for a novice,
might become relative in expert hands.
Also, the choice of intubation technique
in these patients is always influenced by
the clinical findings and X-ray ⁄CT
appearances in the individual patient.
We recognise from his contributions to
the literature that Dr Williamson has
specialist expertise in this area.
However, the management of the
difficult airway was not the principal
focus of our review. The main thrust of
the review, as stated in the introduction,
was to encourage the use of nasotracheal
intubation for routine head and neck
surgery for the benefits offered to the
surgeon as well as to endeavour to
promote maintenance of this apparently
declining skill in the next generation of
anaesthetists. In 1988, Baraka [1], in
response to a letter from Williamson [2]
promoting blind nasal intubation with or
without a stylet in a case with a difficult
airway, similarly mourned the apparent
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1130 � 2003 Blackwell Publishing Ltd
passing amongst colleagues of the blind
nasal intubation skill in favour of fibre-
optic intubation. Thus, in our review,
we sought to offer simple guidance to
both sceptics and trainees in respect of
nasal preparation, choice of tube and
technique of nasal intubation so as to
minimise the principal complication of
nasal bleeding that is often advanced as a
reason for avoiding the technique. The
anaesthetist who gains experience in
the technique of nasal intubation may
acquire the skill of blind nasal intubation
and eventually come to value this capa-
bility amongst other talents in the
acute ⁄ emergency situations cited by
Dr Williamson in his letter.
L. E. Shutt
C. E. J. Hall
St Michael’s Hospital,
Bristol BS2 8EG, UK
E-mail: [email protected]
References1 Baraka A. Endotracheal intubation
in temporomandibular ankylosis.
Anesthesia and Analgesia 1988; 67:
603.
2 Williamson R. Endotracheal intuba-
tion in temporomandibular ankylosis.
Anesthesia and Analgesia 1988;
67: 602–3
Capnography during fibreopticintubation
A tracheal tube may inadvertently
migrate into the oesophagus, even when
a fibrescope has been correctly inserted
into the trachea during fibreoptic intu-
bation [1–3]. The incidence of the tip of
a tube migrating toward the oesophageal
inlet can be high: in one report, this
occurred in four of 10 patients (40%) [4],
whereas it occurred in eight of 13
patients (62%) when a tube was passed
over a gum elastic bougie [5]. Inadvert-
ent insertion of a tube into the oeso-
phageal inlet may be noticed and the
tube pulled back, because there may be
resistance when a tube pushes the mid-
segment of the fibrescope into the
oesophagus [4]. Nevertheless, oeso-
phageal intubation may sometimes
be unnoticed and the tube might be
advanced fully and the fibrescope
removed from the trachea in 5–10% of
occasions [2,3]. It will be particularly
inconvenient if, after a successful inser-
tion of a fibrescope with considerable
difficulty in a patient with a difficult
airway, the fibrescope is pulled out of
the trachea due to inadvertent oesopha-
geal intubation. Therefore, any method
that can detect migration of the tip of
the tube into the oesophageal inlet
before inadvertent removal of a fibre-
scope from the trachea would be useful.
We suggest that capnography via a
tracheal tube is useful for this purpose.
A tracheal tube is attached to the
breathing system via a purpose built
swivel connector, and a fibreoptic
bronchoscope is passed through the
swivel connector and the tracheal tube.
Ventilation is controlled manually by
obstructing the mouth and a patent
nostril (or nostrils), during insertion of
a fibrescope into the trachea. After
successful insertion of the fibrescope
into the trachea, the tube is advanced
over a fibrescope while the presence of
the carbon dioxide waveforms is being
confirmed. When the tube is correctly
inserted into the trachea, the carbon
dioxide waveform will continue to
appear. If, in contrast, the tip of the tube
migrates toward the oesophageal inlet,
the carbon dioxide waveform will dis-
appear. By detecting inadvertent inser-
tion of the tube into the oesophagus at an
early stage and withdrawing the tube
(taking care that the fibrescope is also not
removed), the tube is less likely to push
the fibrescope into the oesophagus and
pull the scope out of the trachea.
Wolf and Gravenstein attached a
carbon dioxide sampling tube to the
suction port of the fibrescope to detect
tracheal intubation [6]. We feel that
with our method, the carbon dioxide
waveform is less likely to disappear for
other reasons, such as obstruction of the
suction port by secretions, and migra-
tion of the tip of the tube into the
oesophagus is more likely to be detected
at an early stage.
T. Asai
K. Murao
K. Shingu
Kansai Medical University,
Moriguchi, Osaka, 570–8507, Japan
E-mail: [email protected]
References1 Moorthy SS, Dierdorf SF. An unusual
difficulty in fiberoptic intubation.
Anesthesiology 1985; 63: 229.
2 Koga K, Asai T, Latto IP, Vaughan RS.
Effect of size of a tracheal tube and
the efficacy of the use of the laryngeal
mask for fibrescope-aided tracheal
intubation. Anaesthesia 1997; 52:
131–5.
3 Hakala P, Randall T.Comparison
between two fibrescopes with different
diameter insertion cords for fibreoptic
intubation. Anaesthesia 1995; 50:
735–7.
4 Asai T, Murao K, Johmura S, Shingu
K. Effect of cricoid pressure on the ease
of fibrescope-aided tracheal intubation.
Anaesthesia 2002; 57: 909–13.
5 Dogra S, Falconer R, Latto IP.
Successful difficult intubation. Tracheal
tube placement over a gum-elastic
bougie. Anaesthesia 1990; 45: 774–6.
6 Wolf LH, Gravenstein D. Capno-
graphy during fiberoptic bronchoscopy
to verify tracheal intubation. Anesthesia
and Analgesia 1997; 85: 701–3.
Breathing system malfunctionand the ‘extra circuit’
Obstruction of an anaesthetic breathing
system by a foreign body has recently
been implicated in the death of a patient
[1]. Similar incidents of breathing circuit
blockage are reported in 1 in 5 million
anaesthetics [2]. It may be this rarity
which makes such problems so difficult
to recognise – detecting a breathing
system fault during use requires a high
degree of suspicion. If suspected, rather
than spending valuable time trying to
find the exact cause, the easiest remedy
is to quickly substitute a fresh breathing
system. However, the practice of keep-
ing an extra breathing system on all
anaesthetic machines for use in such
circumstances seems to have become
uncommon. It is also uncommonly
documented and is not mentioned in the
Association of Anaesthetists’ guidelines
on checking anaesthetic apparatus [3].
We have recently reinstated this
practice in our hospital and recommen-
ded that confirming the presence of such
an extra circuit is part of our depart-
ment’s anaesthetic machine checks. It is
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1131
important to remember that however
sophisticated the technology associated
with anaesthesia becomes, simple solu-
tions are often the safest.
O. Sanehi
Trafford General Hospital,
Manchester M41 5SL, UK
E-mail: [email protected]
References1 Press Association. �Neglect� behind
operation death. http://www.
guardian.co.uk/medicine/story/
0,11381,959344,00.html.
2 Department of Health. Chief Medical
Officer Announces Action on Blocked
Breathing. Tubing. Press release:
reference 2002 ⁄ 0320, 2002.
3 Checklist for Anaesthetic Apparatus 2.
Association of Anaesthetists of Great
Britain and Ireland 1997, London.
A replyThank you for asking me to comment
on Dr Sanehi’s letter.
Dr Sanehi is quite correct, both in
recommending that an alternative brea-
thing system should be immediately
available during every anaesthetic, and
also that this is not mentioned in the
1997 Checklist for Anaesthetic Appar-
atus 2, published by the Association of
Anaesthetists.
However, I am concerned that
Dr Sanehi’s recommended solution
may give a false sense of security. In
the tragic case referred to by him, the
blockage in the anaesthetic breathing
system was caused by the disposable cap
of an intravenous giving set occluding a
single-use catheter-mount that had
been stored, loose, in a drawer along
with other catheter-mounts. It would
not be sufficient to merely confirm the
presence of an extra circuit to prevent
such a tragedy. To act as a rapidly
available, complete replacement for the
potential blocked system, every aspect
of that system including filter, catheter-
mount and ⁄ or angle-piece must be
replaced. Furthermore, it must all be
checked as patent to allow free flow of
gases through the whole system; after
all, the fault in the original system may
be a manufacturing fault, with the
replacement system coming from the
same batch. To have a second complete
breathing system checked and immedi-
ately available for each case would
have both cost and safety implications,
as wrapped single-use items should
be kept wrapped until immediately
before use specifically to prevent poss-
ible ingress of foreign bodies.
In July 2002, the Chief Medical
Officer (CMO) set up an Expert Group,
which included representation from the
Association of Anaesthetists, to look into
such incidents and make recommenda-
tions to reduce the likelihood of recur-
rence. The Group is due to report later
this year, and its recommendations are
likely to be far-reaching. Also due out
later this year is the revised Association
publication on checking anaesthetic
equipment, and the laminated �Check-
list� derived from this publication. This
was already due to be revised at the end
of last year to take into account changes
in anaesthetic practice. The widespread
use of sophisticated anaesthetic work-
stations which are, to a degree, self-
checking; the increased use of single-use
disposables in the anaesthetic breathing
system; and the recognition that the
previous version did not extend to
checking every part of the breathing
system, had resulted in a number of
hazard notices issued by the Medical
Devices Agency and had highlighted the
need for new guidelines. Publication has
been delayed to incorporate the recom-
mendations of the CMO’s Expert
Group.
The new AAGBI guidelines �Check-
ing Anaesthetic Equipment 3: 2003�will recommend that the whole brea-
thing system including a new single-use
filter, catheter-mount and airway device
are checked for patency and free flow of
gas immediately before use on each new
patient. Furthermore, because in the
event of failure of some anaesthetic
workstations, all gas flow may cease,
it will be recommended that a self-
inflating bag and oxygen cylinder is
always checked and immediately avail-
able as part of the regular presession
machine check. If, despite the check of
the breathing system immediately prior
to use, a blockage of the system is
suspected, the use of the self-inflating
bag would be more appropriate than
replacing the whole system, and would
immediately differentiate between an
airway problem and a blocked circuit. It
would be very similar to the old strategy
of blowing directly down the tube or
airway in the event of machine or
breathing circuit failure.
Finally, whilst I agree with Dr Sanehi
that simple solutions may often be safer
than sophisticated technology, some
aspects of such technology add consid-
erably to safety. In particular, the use of
capnography at induction will help to
confirm not only correct airway man-
agement, but also a patent circuit.
Furthermore, the use of highly sophis-
ticated simulator training may enable
these rare events to be encountered and
made more familiar in a safe, controlled
environment.
J. A. Carter
Chairman, Safety Committee,
Association of Anaesthetists of
Great Britain and Ireland
E-mail: john.carter@
north-bristol.swest.nhs.uk
Use of a Proseal LMA formaintenance after failedintubation during a modifiedrapid sequence induction
We report a case where unexpected
difficulty was encountered during a
modified rapid sequence induction of
anaesthesia (RSI) and was successfully
managed with a Proseal laryngeal mask
airway (PLMA: Intravent Orthofix,
Maidenhead, UK).
A 50-year-old man with severe oral
steroid dependent asthma and gastro-
oespohageal reflux presented with
appendicitis. Pre-operative assessment
revealed obvious Cushingoid features
(body mass index of 30 kg.m)2), a
Mallampati class I view with normal
neck extension and mandibular protru-
sion. Respiratory examination revealed
a mild polyphonic wheeze in the upper
zones. The patient was premedicated
with nebulised salbutamol and ipratr-
opium bromide.
Prior to induction, the patient’s
airway position was optimised. The
patient was adequately preoxygenated
with an end tidal oxygen concentration
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1132 � 2003 Blackwell Publishing Ltd
of 80%. Anaesthesia was induced with
propofol, fentanyl and succinylcholine
with cricoid pressure. Direct laryngo-
scopy revealed a Cormack and Lehane
grade 3 view with a deep and posterior
larynx. Cricoid manipulation and a
McCoy blade did not improve laryngo-
scopic view. A gum elastic bougie was
passed with difficulty. A tracheal tube
could not be railroaded over the bougie
despite numerous manoeuvres, changes
of tube size and a brief removal of
cricoid pressure. The patient’s oxygen
saturation had fallen to 84%. Ventilation
was possible but difficult with an oro-
pharyngeal airway and jaw thrust with
cricoid pressure. The patient’s oxygen
saturation had improved to 88%.
A size 5 classic laryngeal mask airway
was inserted with brief release of cricoid
pressure during placement then reappli-
cation. Ventilation was inadequate with
peak airway pressures of 32 cm of
water, tidal volumes of 150 ml and a
large leak. Oxygen saturation had not
improved. A size 5 PLMA was then
inserted which provided an excellent
seal and enabled ventilation with tidal
volumes of 600 ml with peak airway
pressures of 26 cm H2O. A gastric tube
was then inserted down the oesophageal
port, which drained gastric contents.
In view of the need for urgent surgery,
reluctance to further instrument the
airway of a brittle asthmatic and satisfac-
tory ventilatory parameters, it was deci-
ded to proceed with surgery at this point.
Surgery and emergence from anaesthesia
both proceeded uneventfully.
The significance of the difficulties
experienced was explained to the
patient and he was provided with a
letter summarizing the events.
The PLMA does not appear in any
currently published airway algorithms
but it is likely to be included in the UK
Difficult Airway Society guidelines
when they are published (J. Henderson.
Difficult Airway Society Meeting, Lon-
don 2002.) The PLMA has been
recommended for use in obstetrics to
salvage failed intubation [1,2] and such a
case recently occurred in this hospital
[3].
Our case is noteworthy as the initial
management of failure to intubate dur-
ing RSI was insertion of a classic
laryngeal mask airway as recommended
in several algorithms [4,5] and routinely
practised by most anaesthetists in this
country [6]. While the classic laryngeal
mask provided a clear airway, ventila-
tion was inadequate because of airway
leak. Substitution with the PLMA pro-
vided a clear airway, reliable ventilation
and access to drain the stomach. In
addition, this is only the second case
reported where the PLMA has been
used to secure the airway after failure to
intubate during RSI and the first in
non-obstetric surgery.
The PLMA was introduced in the
UK in 2001. It has several important
potential advantages over the classic
laryngeal mask in these circumstances.
It allows functional separation of the
gastrointestinal and respiratory tracts [7]
and provides a 50% better airway seal,
which facilitates controlled ventilation
[8]. The drain tube assists in confirma-
tion of correct mask placement [7],
reduces the likelihood of gastric infla-
tion, allows drainage of the stomach and
provides an �escape route� if regurgita-
tion does occur [9]. These potential
advantages must be balanced against
slightly greater difficulty in PLMA
insertion and the likelihood that the
PLMA has a longer learning curve than
the classic laryngeal mask [8]. On the
basis of the available evidence, we
believe the PLMA does offer advantages
in the circumstance of failed urgent
intubation in a patient with a potentially
full stomach.
Finally, it is of further interest that two
cases of failed intubation during RSI
both managed with a PLMA should be
reported from the same hospital. This
department has considerable experience
with the PLMA; trainees are taught in its
use during elective cases and the PLMA
has been part of our difficult airway
trolley for over a year. It is likely that
theoretical knowledge and practical
familiarity with the PLMA has meant
that trainees are confident to use the
PLMA during these difficult cases.
S. Baxter
A. Brooks
T. Cook
Royal United Hospital,
Bath BA1 3NG, UK
References1 Levy DM. Anaesthesia for Caesarean
section. British Journal of Anaesthesia
Continuing Education and Professional
Development 2002; 1: 171–6.
2 Ovassapian A. Management of failed
intubation in a septic patient. British
Journal of Anaesthesia 2003; 91:
154–5.
3 Awan R, Nolan JP, Cook TM. The
use of a Proseal LMA for airway
maintenance during emergency.
Caesarean section after failed tracheal
intubation. British Journal of Anaesthesia
2003.
4 Benumof JL. Laryngeal mask airway
and the ASA difficult airway algo-
rithm. Anesthesiology 1996; 84: 686–
99.
5 Crosby ET, Cooper RM, Douglas MJ,
Doyle DJ, Hung OR, Labrecque P,
Muir H, Murphy MF, Preston RP,
Rose DK, Roy L. The unanticipated
difficult airway with recommenda-
tions for management. Canadian
Journal of Anaesthesia 1998; 45:
757–76.
6 Morris J, Cook TM. National survey of
rapid sequence induction. Anaesthesia
2001; 56: 1090–7.
7 Brain AIJ, Verghese P, Strube PJ. The
LMA �Proseal� – a laryngeal mask with
an oesophageal vent. British Journal of
Anaesthesia 2000; 84: 650–4.
8 Cook TM, Nolan JP, Verghese C et al.
RCT of the Proseal with the Classic
LMA in unparalysed patients. British
Journal of Anaesthesia 2002; 88: 527–
33.
9 Keller C, Brimacombe J, Kleinsasser
A, Loekinger A. Does the Pro-Seal
laryngeal mask airway prevent
aspiration of regurgitated fluid?
Anesthesia and Analgesia 2000; 91:
1017–20.
ProSeal exchange using a gumelastic bougie in the lateralbody position
A healthy 40-year-old male was sched-
uled for removal of a femoral plate in
the lateral position. After induction of
anaesthesia in the supine position
and easy facemask ventilation, a size 5
ProSealTM laryngeal mask airway
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1133
(PLMA), which had passed the preuse
check tests, was inserted (using the
digital technique) with some difficulty
(small mouth and sharp teeth), the cuff
inflated with 30 ml air and the tubing
taped to the face. The PLMA was
correctly positioned, as judged by
adequate ventilation, a lack of oropha-
ryngeal or drain tube air leaks, and easy
passage of a gastric tube. During sur-
gery, however, an oropharyngeal leak
developed. Palpation of the pilot bal-
loon revealed that the cuff had sponta-
neously deflated. More air was added,
but the balloon remained deflated,
indicating that the cuff, inflation line
or pilot balloon had been damaged. To
replace the PLMA, the gastric tube was
removed and a lubricated gum elastic
bougie (GEB) was inserted into the
drain tube with its straight end first, and
advanced without resistance into the
proximal oesophagus. The damaged
PLMA was then removed over the
GEB and the replacement PLMA inser-
ted using the GEB as a guide, as
previously described [1]. The replace-
ment PLMA functioned perfectly with-
out an oropharyngeal leak. The GEB
was removed and the gastric tube
reinserted. Inspection of the removed
PLMA revealed a small tear on the
posterolateral aspect of the ventral cuff
consistent with damage from teeth. The
patient’s oxygen saturation remained
above 98% throughout and there were
no sequelae.
J. Brimacombe
T. Diprose
Cairns Base Hospital,
Cairns, Australia
E-mail: [email protected]
Y. Lim
Kerdang Kerbau Woman’s and
Children’s Hospital,
Singapore
C. Keller
Leopold-Franzens University,
Innsbruck, Austria
Reference1 Howarth A, Brimacombe J, Keller C.
Gum elastic bougie-guided insertion of
the ProSeal laryngeal mask airway.
A new technique. Anaesthesia and
Intensive Care 2002; 30: 624–7.
Lingual tonsil hypertrophy:airway management
�The tissue at the base of the tongue is
a most fertile source of trouble� [1].
Lingual tonsil hypertrophy (LTH) is
one such tissue. Tokumine et al. report
their case of an 11-year-old-patient
with severe bleeding following planned
lingual tonsillectomy (Tokumine et al.
Anaesthesia 2003; 58: 390–1). We
report here our experience in man-
aging severe bleeding from unantici-
pated and asymptomatic LTH in a
patient presenting for maxillofacial sur-
gery.
Following induction of anaesthesia,
direct laryngoscopy with a size 3
Macintosh blade was impossible. A
mass of polypoid tissue arising from
the tongue base obliterated the pa-
tient’s vallecula and completely ob-
scured the glottis, and bled freely
following instrumentation. External
laryngeal pressure did not improve
the view.
Facemask ventilation was restarted
and pharyngeal suction applied, but
the bleeding continued. With contin-
ual pharyngeal suction, a Miller 4
straight blade laryngoscope was chosen
and a �paraglossal straight blade tech-
nique� [2] was used. The blade was
advanced from the right side of the
patient’s mouth into the groove be-
tween the tongue and the palatine
tonsil base, passing the blade tip
posterior to the epiglottis with eleva-
tion to expose the posterior commis-
sure. The view was further improved
by an assistant providing external
laryngeal pressure, allowing a gum
elastic bougie and a size 7.0 tracheal
tube to be passed into the trachea
under direct vision.
Whilst the Macintosh technique
failed, the paraglossal straight blade
succeeded.
An urgent consultant ENT opinion
was sought and it was decided that
surgical reduction of the lesion was
needed for haemorrhage control.
In the first postoperative hour, there
was severe surgical site bleeding which
needed further treatment under general
anaesthesia. A rapid sequence induc-
tion of anaesthesia with cricoid
pressure was done. On this occasion,
Macintosh laryngoscopy was chosen,
which showed a Cormack and Lehane
Grade 2 view and the trachea was
successfully intubated with an oral
and then a nasal tracheal tube. Hae-
mostasis was achieved, and a gastric
tube was passed to allow drainage of
blood. Recovery was uncomplicated
thereafter.
LTH is implicated in major prob-
lems in airway management. Difficult
or failed facemask ventilation with
resort to the laryngeal mask airway is
described [3–7]. Davies et al. report
the anaesthetic management of three
patients found to have unexpected
LTH [6]. One patient needed a laryn-
geal mask for rescue, but when this
was removed, complete airway
obstruction occurred, which needed
two cricothyroidotomies. However,
difficulty in using a laryngeal mask in
a patient with LTH is reported [8] and
it has been suggested that the laryngeal
mask airway could worsen the situation
by either pushing the tonsillar tissue to
block the glottic opening or causing
more bleeding [9].
The �cannot-intubate-cannot-venti-
late� situation has been reported
[6,10,11]. In each case, emergency
tracheostomy was done, but death fol-
lowed in one case [11].
Ovassapian et al. have reported the
largest series, to date, on unanticipated
difficult airway management with
LTH [7]. Thirty-three patients were
identified with unexpected failed tra-
cheal intubation using conventional
laryngoscopes. Of these, facemask ven-
tilation was difficult or impossible in
12 (35%) and the laryngeal mask
airway was used for rescue in two.
Awake flexible endoscopy showed that
all these patients had unrecognised
LTH.
In our case, straight blade laryngo-
scopy succeeded when the conven-
tional Macintosh technique failed.
LTH can be asymptomatic and unpre-
dictable. Effective airway management
is essential in the presence of LTH
and a range of equipment and skills
should be readily available. We
believe that straight blade techniques
are undervalued, but are potentially
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1134 � 2003 Blackwell Publishing Ltd
lifesaving in some difficult airway
scenarios.
M. Al Shamaa
P. Jefferson
D. R. Ball
Dumfries and Galloway Royal
Infirmary,
Dumfries DG1 4AP, UK
E-mail: [email protected]
References1 Elia JC. Lingual tonsillitis. Annals of the
New York Academy of Sciences 1959; 82:
52–6.
2 Henderson JJ. The use of paraglossal
straight blade laryngoscopy in difficult
tracheal intubation. Anaesthesia 1997;
52: 552–60.
3 Biro P, Shahinian H. Management of
difficult intubation caused by lingual
tonsil hyperplasia. Anesthesia and
Analgesia 1994; 79: 389.
4 Conacher ID, McMahon CC, Meikle
D. �Chicane-like� airway as a compli-
cation of lingual tonsils. Lancet 1996;
384: 475.
5 Dell RG. Upper airway obstruction
secondary to a lingual tonsil. Anaes-
thesia 2000; 55: 393.
6 Davies S, Ananthanarayan C, Castro
C. Asymptomatic lingual tonsil
hypertrophy and difficult airway
management: a report of three cases.
Canadian Journal of Anaesthesia 2001;
48: 1020–4.
7 Ovasappian A, Glassenberg R,
Randel GI, Klocte A, Mesnick PS,
Klafta JM. The unexpected difficult
airway and lingual tonsil hyperplasia.
A case series and a review of the
literature. Anesthesiology 2002; 97:
124–328.
8 Fundingsland BW, Benumof JL. Dif-
ficulty using a laryngeal mask airway in
a patient with lingual tonsil hyper-
plasia. Anesthesiology 1996; 84: 1265–6.
9 Andrews SR, Mabey MF. Tubular
fiberoptic laryngoscope (Wu Scope)
and lingual tonsil airway obstruction.
Anesthesiology 2000; 93: 904–5.
10 Johnson CA, Mehdiabadi RJ, Ruff T.
Infection and hypertrophy of the
lingual tonsil as a cause of airway
obstruction. Texas Medicine 1986; 82:
29–31.
11 Jones DH, Cole SD. Unanticipated
difficult airway secondary to lingual
tonsillar hyperplasia. Anesthesia and
Analgesia 1993; 77: 1285–8.
No pressure! Just feel theforce...
Many methods have been proposed for
demonstrating the force required for
cricoid pressure, or Sellick’s manoeuvre
[1–3]. I recently learnt of perhaps the
simplest and most elegant of these, and
in testing its theory, realised that as well
as being a convenient demonstration, it
also serves as a good teaching aid for the
First Gas Law. There has been much
controversy over the amount of force
that should be applied during Sellick’s
manoeuvre, and in common with other
authors, I have settled on 30 N in this
model [3].
The plunger of a 20-ml syringe (B-D
Plastipak) is withdrawn to the 20 ml
mark so that the syringe contains 20 ml
of air. The end is then occluded with an
obturator (Vygon dualend stopper; a
push-and-twist technique is recommen-
ded for reasons that will become obvi-
ous when tried in practice). Depressing
the plunger to the 10 ml mark requires
a force of 30 N to be exerted by the
operator’s fingers.
The physics of this model illustrate
the First Gas Law (Boyle’s Law). At
equilibrium, with 20 ml contents of air
(¼ 2 · 10)5 m3) (V1) at normal atmo-
spheric pressure, the pressure in the
syringe (and hence acting on the plun-
ger) is atmospheric, 101.325 kPa ¼101325 Pa (P1).
The area of the plunger of the 20 ml
syringe may be calculated from its
internal diameter, 19.5 mm. Internal
radius (r) is thus 9.75 mm ¼ 9.75 ·10)3 m. Plunger area (pr2) is thus
2.98 · 10)4 m2.
Since Pressure ¼ Force ⁄ Area; re-
arranging gives Pressure · Area ¼Force. The force applied to plunger by
atmospheric pressure is therefore
P1 multiplied by plunger area,
101325 Pa · 2.98 · 10)4 m2 ¼ 30.2 N
When the plunger of our syringe is
depressed to 10 ml contents, the pres-
sure in the syringe increases according
to Boyle’s Law, which states that at
constant temperature the volume of a
given mass of gas varies inversely with
the absolute pressure. It is often expres-
sed as P1V1 ¼ P2V2. Rearranging
gives P2 ¼ P1V1 ⁄V2. Substituting our
values, the pressure in our syringe (P2)
when plunger is depressed to 10 ml
contents (¼ 1 · 10)5 m3) (V2) is
101325 Pa · 2 · 10)5 m3 ⁄1 · 10)5 m3 ¼202650 Pa (i.e. twice atmospheric
pressure).
At equilibrium, with plunger dep-
ressed to 10 ml content, force on plunger
is P2 multiplied by plunger area,
202650 Pa · 0.000298 m2 ¼ 60.4 N.
Given that 30.2 N of this force is due
to atmospheric pressure, force exerted
by fingers is thus: 60.4 N – 30.2 N ¼30.2 N.
Q.E.D. the force required to depress
plunger of 20 ml syringe from 20 ml
volume of air to 10 ml volume of air
against closed end is 30.2 N, approxi-
mately equal to the 30 N force recom-
mended for cricoid pressure.
Whilst thinking of forces and pres-
sures in the above calculations, the
misnomer of cricoid pressure is obvious,
since we talk in units of force (Newtons)
when referring to its strength. To
illustrate this, a transparent plastic film
(Tegaderm) was applied to the anterior
aspect of my neck and I adopted the
position of a patient about to undergo
application of cricoid pressure (sic).
With gloved hands and inked fingers
an operating department practitioner
(ODP) from our department performed
Sellick’s manoeuvre on me in his nor-
mal manner (for a very short period of
time!). The imprint of his two-fingered
technique was left in ink on the plastic
film. The film was then stuck on graph
paper and squares counted to estimate
the area of contact, which was
308 mm2, or 3.08 · 10)4 m2. Since
Pressure ¼ Force ⁄ Area, if a force of
30 N is applied to an area of 3.08 ·10)4 m2, the pressure resulting is 9.7 ·104 Pa, or 97 kPa, i.e. nearly one
atmosphere of pressure.
Pedantic I know, but until we start
asking our assistants to apply one atmo-
sphere of pressure during Sellick’s man-
oeuvre, shouldn’t cricoid pressure be
more correctly known as cricoid force?
There we have it, a cheap and
convenient way to demonstrate the
force required for Sellick’s manoeuvre,
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1135
and a practical demonstration of the Gas
Laws and simple physics terminology.
Should pass the time on the next
teaching list!
N. P. Wilson
Broomfield Hospital,
Chelmsford CM1 7ET, UK
References1 Ashurst N, Rout CC, Rocke DA,
Gouws E. Use of a mechanical simu-
lator for training in applying cricoid
pressure. British Journal of Anaesthesia
1996; 77: 468–72.
2 Flucker CJ, Hart E, Weisz M, Griffiths
R, Ruth M. The 50 millilitre syringe
as an inexpensive training aid in the
application of cricoid pressure. Euro-
pean Journal of Anaesthesiology 2000; 17:
443–7.
3 Clayton TJ, Vanner RG. A novel
method of measuring cricoid force.
Anaesthesia 2002; 57: 326–9.
One handed central linetechnique
Many people are unaware that you do
not have to use the feeder to straighten
the J tipped guide wire of central lines.
Although guide wires are supplied
preloaded into introducers, after one
attempt they have to be reloaded to
straighten the guide wire tip.
This is a two-handed procedure
which means letting go of the introducer
needle which could then be dislodged.
The pictures below demonstrate that the
tip can be easily straightened by clasping
the proximal part of the wire in the palm
and using the thumb and first finger to
apply traction through the wire (Fig. 3).
This pushes the external portion of the
wire over its inner core making it
extend. Once the traction is removed
(when the tip is in the vein), the wire
curls again, retaining this safety feature.
M. Wilson
Sevenoaks TN14 7HF, UK
E-mail: [email protected]
Evaluation of an insulatedTuohy needle system for theplacement of interscalenebrachial plexus catheters
I read with interest the recent article
(Denny et al. Anaesthesia 2003; 58:
554–7), which stated in the introduc-
tion that �Indeed, a study by Singelyn
et al. reported an 80% incidence of
difficulties with catheter placement
when using a Seldinger technique.�;they are, however, mistaken. In our
study [1], difficulty (i.e. more than 2
attempts) at insertion of the catheter
was noted in eight out of 60 patients,
i.e. an incidence of 13% (in our article,
the table is expressed in percentage and
not in number of patients). In their
study, they reported a �difficult� (i.e.
score of 3 on a 5-level scale) catheter
threading in 2 ⁄ 20 patients (in Table 2),
i.e. an incidence of 10%. Thus, from
both studies, it appears that insertion of
an interscalene brachial plexus catheter
remains problematic in about 10% of
patients, whatever the equipment used.
The suggested superiority of a Tuohy
needle system over a Seldinger tech-
nique is not substantiated by data and
remains thus controversial.
F. J. Singelyn
St Luc Hospital,
Brussels, Belgium
Reference1 Singelyn FJ, Seguy S, Gouverneur JM.
Interscalene brachial plexus analgesia
after open shoulder surgery: continuous
versus patient-controlled infusion.
Anesthesia and Analgesia 1999; 89:
1216–20.
A replyWe thank Dr Singelyn for his comments
on our paper and we must apologise for
misinterpreting the data in his paper. We
agree with his comment that our results
in terms of difficulty in threading cath-
eters are probably similar to his. How-
ever, we do not believe that this
interpretation adversely affects the pri-
mary purpose of our study, which was to
evaluate a new catheterisation system
that we had not used before. The
important issue was not whether we
were as good as Dr Singelyn when using
the new equipment, but whether our
results improved when changing from a
�cannula over needle ⁄ catheter through
cannula� technique to the new �catheter
through Tuohy needle� technique. Our
conclusion was that our success rate was
substantially increased by the use of the
new equipment.
Had Dr Singelyn read our paper with
the assiduity with which we should
have read his, he would have appreci-
ated that at no point did we suggest that
the Tuohy technique is superior to the
Seldinger technique; such a statement
could only have resulted from a con-
trolled comparison of the two tech-
niques. May we draw his attention to
the conclusion in the summary of our
paper: �It is concluded that the insulatedFigure 3 J wire straightened by applying traction through the wire with thumb and first finger.
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1136 � 2003 Blackwell Publishing Ltd
Tuohy needle system for interscalene
catheterisation proved easy to use in the
hands of someone who had not used it
before, and can be recommended�? We
stand by this conclusion.
N. M. Denny
N. Barber
D. J. Sildown
E-mail: nick@crimplesham.
demon.co.uk
Prolonged succinylcholineapnoea resulting fromacquired deficiency of plasmacholinesterase
A course of chemotherapy was pre-
scribed for a 65-year-old male with
non-Hodgkins lymphoma. He had no
other significant medical history. The
patient was given a high dose combina-
tion, which included cyclophosphamide,
doxorubicin, vincristine and predniso-
lone. Following his first dose, he became
severely depressed and refused further
chemotherapy. He was admitted to the
psychiatric ward and treatment was com-
menced with venlafaxine, olanzapine
and lithium. As his condition did not
improve with antidepressant drugs, a
course of electroconvulsive therapy
(ECT) was started. After three unevent-
ful ECT treatments, he improved suffi-
ciently to restart his chemotherapy.
After the fourth ECT treatment,
however, he suffered a prolonged
apnoea. He received the same dose of
thiopental (200 mg) and succinyl-
choline (40 mg) as in previous treat-
ments. The ECT was uneventful but
spontaneous respiration did not return
for 45 min. During this time his lungs
were ventilated with oxygen. The
ECG, blood pressure, oxygen saturation
and end-tidal CO2 were monitored and
midazolam 1 mg was administered to
prevent awareness. Testing with a per-
ipheral nerve stimulator after approxi-
mately 30 min showed four equal
twitches with the train of four. The
patient recovered fully and denied any
awareness. Blood samples were taken
for urea and electrolytes, lithium level
and cholinesterase estimation.
The first three ECTs were adminis-
tered at least 3 weeks after the first dose
of chemotherapy. The fourth ECT with
prolonged apnoea was carried out on
the day following the second dose of
chemotherapy and we felt that this
episode was related to the short interval
between chemotherapy and ECT.
The blood results are summarised in
Table 6 and the low plasma choli-
nesterase level confirmed our suspi-
cions.
Normally, 90–95% of succinylcho-
line is metabolised in the bloodstream
by plasma cholinesterase, leaving only
5–10% to reach the neuromuscular
junction. A deficiency of plasma choli-
nesterase will therefore result in a
relative overdose, which may even
result in a phase II block.
There have been reports of pro-
longed succinylcholine apnoea follow-
ing cyclophosphamide administration.
Many other drugs that are hydrolysed in
the circulation by plasma cholinesterase
have been found to prolong the action
of succinylcholine by differing degrees.
These interactions should be anticipated
especially in short procedures such as
ECT and it would therefore seem wise
to avoid succinylcholine if possible for
at least 3 weeks following high dose
chemotherapy with cyclophosphamide.
J. C. Norris
Barnet General Hospital,
Barnet EN5 3DJ, UK
E-mail: [email protected]
Use of vegetarian propofolin Jain community of India
A 6-year-old male child of the Jain
community of India presented in the
casualty department of our hospital with
a foreign body (bead) in the left ear.
The child was in agony and was rest-
less. Removal of the foreign body was
planned. Pre-anaesthetic assessment
revealed a history of a febrile convulsion
6 months previously. The mother also
informed us that the child had a cold
and runny nose for the last 2 days.
Clinical examination of the child was
within normal limits. When the anaes-
thesia plan was being discussed, the
mother interrupted the discussion say-
ing that she was not willing for any
medication of animal origin to be
administered. On inquiring her reasons,
we found that she belonged to the Jain
community, which is strictly vegetarian
because of religious beliefs. To respect
these beliefs, we conducted the short
procedure under total intravenous anaes-
thesia TIVA using glycopyronnium,
pentazocine and Cleofol� (Themis
Medicare Limited). The latter, a formu-
lation of propofol, has been recently
introduced in the market and it dose not
contain egg lecithin or any other animal
byproduct in its formulation.
Cleofol� can be used in patient’s who
are strictly vegetarian because of their
religious beliefs. Its use is also recom-
mended in patients allergic to egg.
M. Munjal
D. Sood
V. K.Gupta
A. Singh
T. K. Kaul
D.M.C. & Hospital,
Ludhiana – 141001, Punjab, India
E-mail: [email protected]
Remifentanil for the painof pancreatitis
We wish to report the use of remifen-
tanil as an analgesic in a patient breathing
spontaneously who suffered severe and
prolonged respiratory depression with
morphine and pethidine.
An 81-year-old female presented to
the emergency admissions unit with a
4-day history of acute abdominal pain,
unwell with vomiting and constipation.
Her previous medical history included
chronic renal failure in addition to
congestive cardiac failure and a thoraco-
plasty for old tuberculosis. She was a
deaf mute but despite all this lived a
happy and independent life. She usually
took coamilofruse and dothiepin.
Auscultation showed bibasal crepita-
tions, normal heart sounds and no
murmurs.
Urea and electrolytes: normalSerum lithium: less than therapeutic
levelDibucaine number: 73 (Normal 76–83)Fluoride number: 53 (Normal 56–65)K002 ⁄ 0683 number: 86 (Normal 93–98)Plasma cholinesterase: 339 units ⁄ l (Normal
600–1400)
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1137
The abdomen was soft but generally
tender with no guarding, rigidity or
palpable mass. The only abnormality on
chest X-ray was a previous thoraco-
plasty. A CT scan of the abdomen and
pelvis showed a small amount of free
fluid in the pelvis, an inflamed pan-
creas and a large abdominal aortic
aneurysm. Blood results showed urea
21 mmol.l)1, creatinine 279 lmol.l)1,
serum sodium 144 mmol.l)1, potassium
4.4 mmol.l)1, albumin 23 gl)1, calcium
2.16 mmol.l)1, amylase 961 IUl)1,
C-reactive protein 203 mgl)1 and nor-
mal liver function tests, and a diagnosis
of acute pancreatitis was made. She was
given 50 mg of pethidine for pain relief.
An ICU referral was made.
On examination, she was hypoxic
with an oxygen saturation of 86% on
air, hypotensive with blood pressure of
90 ⁄ 50 mmHg, She had a tachycardia
and appeared dehydrated; shortly there-
after, she became cyanosed and uncons-
cious. Her blood gases were PaO2
5.92 kPa, PaCO2 8.05 kPa and pH 7.3.
There was discussion at the time
about the appropriateness of intensive
care. The recognition of pinpoint pupils
and the administration of 0.4 mg of
naloxone for opioid toxicity reversed
the respiratory depression. An infusion
of 200 mg.h)1 of naloxone was started
so that she breathed adequately and was
awake without pain. The infusion of
naloxone was stopped 6 h later. After
the infusion was stopped for 2 h, she
was in pain again, so the ward staff gave
her 10 mg of intravenous morphine.
She was treated with fluids and
antibiotics. After assessment by the
ICU outreach team, she was given
intravenous naloxone 0.4 mg, which
reversed both her drowsiness and her
respiratory depression.
Despite all this she appeared to be
improving. She was therefore admitted
to the ICU for monitoring and anal-
gesia. At this stage, an epidural was
considered, but fear of cardiovascular
instability in a frail, elderly patient with
acute pancreatitis along with the risk of
accumulation of local analgesic agents
prevented this.
Remifentanil by infusion at a con-
centration of 100 lg.kg)1 was started at
a rate of 2 ml.h)1 (2.8 lg.kg)1.h)1); this
was given for 3 days. She was awake,
pain free at rest and breathing well with
a good gas exchange. When the need for
interventions such as changing position,
sheet changes or personal hygiene that
caused her distress and further pain, we
were able to titrate the infusion rate up
to 4 ml.h)1 (5.6 lg.kg)1.h)1) to relieve
this. On the fifth day she was converted
to an epidural and subsequently dis-
charged back to the surgical ward.
Remifentanil hydrochloride is a
potent opioid mu receptor agonist
with rapid onset of action; its biologi-
cal half-life is < 10 min [1,2]. These
features of quick peak effect and rapid
offset once the infusion is stopped
make it readily titratable and even after
prolonged use the effects of remifent-
anil do not accumulate. Also its clear-
ance is independent of renal and liver
function [3,4].
It is important to note that we are not
advocating widespread use of remifent-
anil for pain from pancreatitis or other
causes for patients who are not receiv-
ing mechanical ventilation or in a high
dependency area. This patient had spe-
cific difficulties with more conventional
opioids. The use of remifentanil was
also carefully monitored in ICU. This
patient illustrates remifentanil can be an
effective analgesic and easily titrated to
provide analgesia with minimal respir-
atory depression. If too much is given,
the infusion rate can be decreased and
the effects will disappear quickly. This is
unlike conventional opioids, when an
infusion of a short-acting antagonist
(naloxone) is needed.
In summary, this case shows remi-
fentanil can be used as an effective
predictable analgesia on its own in a
spontaneously ventilating patient.
S. T. Gopal
M. P. Lane
G. R. Park
Addenbrooke’s Hospital
Cambridge CB2 2QQ
E-mail: [email protected]
References1 Kapila A, Glass P, Jacobs JR, et al.
Measured context sensitive half
times of remifentanil and alfentanil.
Anesthesiology 1995; 83: 968–75.
2 Cohen J, Royston D. Remifentanil.
Current Opinions in Critical Care 2001;
7: 227–301.
3 Park GR, Evans N. Remifentanil in the
critically ill-what will its place be?
British Journal of Intensive Care 1996;
79: 330–6.
4 Breen D, Wilmer A, Bodenham A, Bach
V, Kessler P, Albrecht S, Shaikh S. The
offset of pharmacodynamic effects of
remifentanil in ICU patients is not
affected by renal impairment. Intensive
Care Medicine 2001; 27 (S2): S207.
An unusual cause of diabeticketoacidosis
A 39-year-old female patient was admit-
ted to the Intensive Care Unit with
diabetic ketoacidosis, following a one-
day history of vomiting. There had been
nochange inher diet.With the exception
of her history of temporal lobe epilepsy,
systematic inquiry revealed nothing else
of note. She had been diagnosed with
Type I diabetes at 4 years of age. Her
insulin requirements were 18 U of
Humalin M� twice daily and had been
consistent for some time. She took
Tegretol� twice daily for control of her
epilepsy. On examination she was alert
tachycardic, dehydrated and tachy-
pnoeic. The smell of ketones was detec-
ted on her breath. Blood results
outside normal parameters were as fol-
lows: Plasma glucose concentration of
26.3 mmol.l)1, [H+] of 106.2 nmol.l)1,
a Base deficit of )26 mmol.l)1, Paco2 of
2.2 kPa, Pao2 of 17.7 kPa, [K+] of
6.1 mmol.l)1, PCV of 51.2% and a
WBC count of 24.7 · 109.l)1. Standard
treatment for diabetic ketoacidosis was
initiated and she improved over the
next 2 days wherein the WBC count
decreased to 13.9 · 109.l)1.
On further questioning, the patient
reported that she had changed the
cartridge of her insulin pen 3 days
previously. On inspection of the Hum-
apen�, a cracked cartridge (Fig. 4) was
only apparent once removed from the
Humapen�. The smell was characteris-
tic of insulin (smells of Band Aids�).
Although she had a raised white cell
count, no underlying focus of infection
was found. Leakage of the insulin
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1138 � 2003 Blackwell Publishing Ltd
during administration appears to be the
primary cause of her ketoacidosis and
even with an underlying infection,
could only have added to her develop-
ment of ketoacidosis.
This illustrates the importance of
checking drugs before administration,
but also begs the question whether
the design of the Humapen� needs
re-evaluation.
A. Myburgh
Warwick Hospital,
Warwick CV34 5BW, UK
E-mail: [email protected]
Sciatic nerve block in amputees
We read with interest the letter �prob-
lems performing a sciatic nerve block in
an amputee� (Lok & Kirk. Anaesthesia
2003; 58: 289–90) and the subsequent
response (MacLeod et al. Anaesthesia
2003; 58: 612–13). We recognise the
authors’ experiences of technically dif-
ficult blocks in amputees. In such cases,
we have utilised the motor response in
the proximal calf of a below-knee
amputee as an end-point for successful
sciatic nerve block. We describe one
example of this technique.
A 54-year-old female was scheduled
for refashioning of left below knee
amputation stump as an elective proce-
dure on a plastic surgery operating list.
Her past medical history included myo-
cardial infarction, seven years previ-
ously, and stable angina. She was on
aspirin and clopidogrel, both of which
she stopped taking a week pre-opera-
tively. She had had previous general
anaesthetics for left below knee ampu-
tation for peripheral vascular disease, and
a revision of amputation. On both
occasions, she suffered from severe
postoperative nausea and vomiting
(PONV).
Our initial plan was to site a lumbar
epidural awake, and a general anaes-
thetic. However, the patient declined
an epidural because of concerns regard-
ing epidural haematoma. She also
refused peripheral nerve blocks whilst
awake. Our aim was to provide her
with optimum postoperative analgesia
with minimum risk of PONV. After
due consideration, it was agreed that the
most suitable option was a general
anaesthetic and a femoral and sciatic
nerve block whilst under general anaes-
thesia. After full and frank discussion
about the potential risks and benefits of
the nerve block while under general
anaesthesia, the patient consented to this
approach.
The general anaesthesia was provi-
ded by fentanyl, propofol and sponta-
neous ventilation with a size 4
laryngeal mask using oxygen, air and
sevoflurane.
The sciatic nerve block was per-
formed by a posterior approach with
the patient in the right lateral position.
Under aseptic precautions, we used a
150-mm, 21-gauge pencil tip needle
(Polymedic UPA) and a Polymedic
Polystim nerve locator to perform the
sciatic nerve block. We were seeking
contractions of the proximal calf mus-
cle to aid localisation of the sciatic
nerve. Initially, we set a current of 3
mA and reduced to 0.7 mA to locate
the nerve. After obtaining visible
motor response in the proximal calf
and negative aspirations for blood,
20 ml of ropivacaine 0.75% was injec-
ted in 5 ml aliquots. Femoral nerve
block was performed with 10 ml of
ropivacaine 0.375% using the nerve
locator. The patient did not require
subsequent opioid analgesia intra-
operatively. She was also provided
with patient-controlled analgesia
(PCA) at the end of the procedure to
cover the possibility of failure of the
peripheral nerve block.
We interviewed the patient 24 h later
to assess the quality and duration of
postoperative analgesia. She was virtu-
ally pain free during this period, and had
not used her PCA at all. She was also
free of PONV.
M. Hariprasad
D. Greig
Wythenshaw Hospital,
Manchester M23 9LT, UK
E-mail: [email protected]
Confirming the position of thethoracic epidural catheter
The observation of Corry and colleagues
(Corry et al. Anaesthesia 2003; 58:
929–30) that a patient who responds
�upwards� when it is suggested as one of
a choice of three in response to the
question: �In which direction is your
catheter threading?� never has a failed or
unilateral block is an interesting one.
Clearly, he and his colleagues have great
experience of this test in their patients. I
look forward to trying it out in patients
for hepatobiliary surgery.
To suggest that their observations
�provide further support for inserting
thoracic epidurals in conscious patients�is nonsense. To provide such support,
one would need a properly conducted
prospective randomised controlled trial,
with block assessment being performed
by a suitably blinded clinician. Since Dr
Corry and colleagues insert many hun-
dreds of thoracic epidurals, they would
be well placed to trial their test scien-
tifically.
J. Isaac
University Hospital, Birmingham,
Birmingham B15 2TH, UK
E-mail: [email protected]
Managing accidentally cutepidural catheters
A recent incident involving a patient’s
epidural catheter raised some interesting
management questions. A pair of non-
sterile scissors were being used to cut to
size the transpore dressing securing the
epidural catheter to the patient’s skin
following insertion. Unfortunately, the
catheter itself was accidentally severed at
the level of the patients shoulder. The
anaesthetist was then left with the
dilemma of choosing one of three
courses of action:
1. Simply removing the cut portion of
catheter and reconnecting the hub of
the filter to the remaining length.
However, the sterility of the interior
of the catheter was no longer assured.
2. Removing the epidural catheter from
the patient and re-siting a fresh one
with the attendant risk of re-instrumen-
tation.
Figure 4
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1139
3. Removing the catheter and aban-
doning epidural anaesthesia to avoid the
risks of re-instrumentation but depri-
ving the patient of the benefit of an
epidural, which was previously consid-
ered to be in their best interests.
A survey of departmental colleagues
revealed that although infrequent, many
had encountered similar accidents dur-
ing their careers. A literature search
revealed only one published example in
a letter from 20 years ago in which the
author recommended reconnection but
gave no consideration to infection risk
[1].
However, the situation is akin to
accidental disconnection of the catheter
from the filter (usually occurring during
a restless nights sleep on a general ward)
as this presents the anaesthetist with the
same dilemma regarding reconnection.
One study has been published which
looks specifically at this problem and the
nature of the risk of pathogen transmis-
sion via the catheter. Twenty-four
epidural catheters were contaminated
at one end with a variety of pathogens
and then incubated to determine if a
segment of the catheter might remain
internally sterile distal to the point of
disconnection. They also tested the
effectiveness of decontaminating the
exterior of the catheter. They found
that 8 h after contamination, no bacteria
were detected more than 20 cm from
the contaminated end of catheters filled
with a saline and fentanyl solution,
provided there had been no significant
displacement of the fluid along the tube
i.e. less than 12.5 cm (remember there
is a negative pressure within the epidu-
ral space).
They also took 10 catheters with
highly contaminated exteriors and
found that soaking them in betadine
for 2 min and airing them for 3 min
before cutting with a sterile blade
precluded bacteria from entering the
catheter on 10 out of 10 occasions [2].
In our situation where the desterilised
catheter had been accidentally cut in the
anaesthetic room, by extrapolation of
these results we can conclude that the
best course of action would be as
follows:
If the fluid within the catheter has
remained static or if the meniscus has
moved less than 12.5 cm, then recon-
nection can be considered.
A segment of catheter distal to the cut
end should be immersed in betadine for
at least 2 min and then allowed to dry
completely to prevent its entry into the
epidural system where it could provoke
arachnoiditis. A sterile blade should
then be used to cut the catheter in the
centre of this cleaned area. The filter
hub can then be safely reconnected.
The issue of how much catheter to
remove may be affected by where the
accidental cut has been made and by
how much catheter remains for it to be
practically useful. The time frame
clearly will be considerably less than
the 8 h in which the bacteria colonised
up to 20 cm of the catheters in the
study. However, if it is possible to
remove in excess of 20 cm of catheter
and retain enough length to be useful,
this would be the ideal as it is evidence-
based with regards to the results of this
study.
Although obvious, it should be added
the easiest solution would be to precut
the transpore before applying it to the
patient, thus preventing such mishaps.
J. Armstrong
Bristol Royal Infirmary,
Bristol BS2 8HW, UK
E-mail: james.Armstrong@
blueyonder.co.uk
References1 Kay J, Rouman WC. Technique for
rejoining cut epidural catheter.
Anesthesia and Analgesia 1984; 63: 783.
2 Langevin PB, Gravenstein N, Langevin
SO, Gulig PA. Epidural catheter
reconnection. Safe and unsafe practice.
Anesthesiology 1996; 85: 883–8.
Scabies: a differential diagnosisof pruritus followingsubarachnoid opioidadministration
I read with interest the correspondence
(Ng & Plaat. Anaesthesia 2003; 58: 399–
400), which describes the anaesthetic
management of a parturient with recur-
rent scabies infection presenting for
elective Caesarean section. I have to
agree with the authors that despite the
worldwide prevalence of this ectopara-
sitic skin disease, no other reports
addressing the anaesthetic implica-
tions and safety of regional anaesthe-
sia in patients with active Sarcoptes
scabiei infestation can be found in the
literature.
The diagnosis of scabies is essentially
clinical [1]. Patients typically present
with a history of recurrent pruritus with
scratch marks in suggestive areas (inter-
digital folds, cubital margins of the
hands, anterior face of the wrists,
anterior axillae, around the navel and
nipples, external genitalia, and the
anterointernal aspect of the thighs),
most often associated with specific signs
(burrow, pearl-like vesicular eruptions
and scabious nodules). The diagnosis is
microscopically confirmed when skin
scrapings of external burrows or papule
material reveal mites, ova or faecal
pellets [2]. In primary infestations, the
incubation time is 15–20 days, but may
sometimes be longer than 6 weeks.
Therefore, initial infestation may be
relatively asymptomatic, and without
suggestive skin lesions for the first
2–6 weeks.
Ectoparasitic skin infestation with
Sarcoptes scabiei remains a common
cause of skin rash and pruritus world-
wide. However, pruritus is also the
most common side-effect of sub-
arachnoid and ⁄ or epidural opioid
administration [3]. Pruritus follows sub-
arachnoid opioid administration more
often in obstetric patients than in any
other patient group, with the incidence
ranging from 40 to 80% of parturients
treated with subarachnoid opioids. Opi-
oid-induced pruritus is typically mild
and involves the face and ⁄ or chest
(breast) area. Occasionally, the intensity
of itching is so annoying that it inter-
feres with sleep and breast-feeding. The
aetiology of opioid-related pruritus is
unclear. To date, no reports have
specifically addressed the coexistence
and ⁄ or the differential diagnosis
between the scabies-related and sub-
arachnoid opioid-related pruritus in a
parturient.
In my practice of obstetric anaesthe-
sia, I encountered a parturient whose
first lifetime diagnosis of primary
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1140 � 2003 Blackwell Publishing Ltd
scabies infection was brought about by
the differential diagnosis of persistent
peripartum itching initially solely
attributed to subarachnoid opioid
administration for labour analgesia
(unpublished data). An otherwise
healthy 29-year-old pregnant woman
at 39 weeks gestation was in labour
(with painful uterine contractions) and
consented to a combined spinal-epidu-
ral analgesia (CSEA), which was per-
formed in a standard manner with an
18-gauge Tuohy-Schliff epidural nee-
dle and a 27-gauge Whitacre spinal
needle. Following the appearance of
CSF at the hub of the spinal needle,
5 lg of fentanyl combined with
2.0 mg of ropivacaine (1 ml of 0.2%
solution) was injected into the sub-
arachnoid space. A 20-gauge multior-
ifice epidural catheter was inserted
5 cm into the epidural space. Aspir-
ation from the epidural catheter was
negative for blood and CSF. The
patient reported pain relief approxi-
mately 2 min after the subarachnoid
injection.
However, approximately 10 min
later, she reported onset of moderate
to severe pruritus involving the chest
(breasts), mid abdomen, lower back,
anterolateral thighs, perineum and the
buttocks. Interestingly, the patient
reported no facial (perioral) pruritus.
Treatment with subhypnotic doses
of intravenous propofol (10 mg) and
small doses of intravenous naloxone
(0.08 mg) provided no relief of pruri-
tus, which continued throughout the
course of her labour, the uneventful
vaginal delivery and into the postpar-
tum period. Consultation with the
dermatologist, aided by the micro-
scopic skin scraping examination,
established the diagnosis of primary
scabies infection and the patient admit-
ted to recent (6 weeks prior) travel to
rural regions in South America.
In conclusion, it is difficult to spe-
culate if the onset of scabies-related
pruritus in our patient (which seemed
to have been triggered by subarachnoid
opioid administration) would have
been significantly delayed had the
patient not received subarachnoid opi-
oids for labour analgesia. It is also
possible that initially the coexistence of
opioid-induced and scabies-induced
pruritus was responsible for our pati-
ent’s symptoms.
K. M. Kuczkowski
University of California San Diego,
San Diego, California, USA
E-mail: [email protected]
References1 Buffet M, Dupin N. Current treat-
ments for scabies. Fundamental of
Clinical Pharmacology 2003; 17:
217–25.
2 Judge MR, Kobza-Black A. Crusted
scabies in pregnancy. British Journal of
Dermatology 1995; 132: 116–19.
3 Riley ET, Ross RK. Epidural and
Spinal Analgesia ⁄ Anesthesia: Section
II. Opioid Techniques. In: Chestnut,
DH, ed. Obstetric Anesthesia: Principles
and Practice. Mosby, St. Louis 1999,
pp. 386–408.
A new sign of successfulpaediatric caudal placement
Caudal block is one of the most com-
mon methods of regional blockade used
by UK paediatric anaesthetists [1]. In
children, it is a quick and simple
technique, with low complication and
failure rates [2]. Several methods exist to
confirm correct needle placement.
These include the �whoosh� test, the
�swoosh� test, the use of a peripheral
nerve stimulator, and bulging of the
sacrococcygeal ligament [3–5]. We des-
cribe the �kink� sign of successful caudal
placement in children.
The sacral hiatus is palpated, and a
22G or 24G intravenous cannula is
inserted at an angle of 45� to the
sacrococcygeal membrane. Usually, a
distinct �pop� can be felt as the needle
passes through this membrane. The
needle is then immobilised and the
catheter advanced into the caudal canal
with very little resistance. Overt dural
and venous puncture is excluded by
opening the cannula to air for 30 s. After
initial aspiration, local anaesthetic is
injected, with further intermittent aspir-
ation for blood and CSF. When the
cannula is removed, a visible �kink� at
approximately 4 mm from the exit point
at the skin is seen (Fig. 5, indicated by
white arrow). MRI studies of the caudal
canal, would suggest that this corres-
ponds to the depth of the caudal canal
adjacent to the point of entry at the
sacrococcygeal membrane [6]. The
�kink� is probably formed when
the cannula, having passed through the
sacrococcygeal membrane, hits the sac-
rum on the opposite side of caudal canal,
bends, and is driven in a cephalad
direction up the canal. This �kink� is a
useful confirmatory sign of correct cau-
dal placement, and demonstrates the
cannula has been correctly sited in the
caudal canal when the local anaesthetic
was delivered.
O. Hill
S. Rolfe
Manchester Royal Infirmary,
Manchester M13 DWL, UK
References1 Sanders JC. Paediatric regional
anaesthesia, a survey of practice in the
United Kingdom. British Journal of
Anaesthesia 2002; 89: 707–10.
2 Dalen B, Hasnaoui A. Caudal
anesthesia in paediatric surgery:
success rate and adverse effects in 750
consecutive patients. Anesthesia and
Analgesia 1989; 68: 83–9.
3 Orme RM, Berg SJ. The �swoosh�test – an evaluation of a modified
�whoosh� test in children. British
Journal of Anaesthesia 2003; 90:
62–5.
4 Tsui BCH, Tarkilla P, Gupta S,
Kearney R. Confirmation of caudal
needle placement using nerve stimu-
lation. Anesthesia and Analgesia 1999; 91:
374–8.
Figure 5
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1141
5 Schwartz RE, Stayer SA, Pasquariello
CA. An additional sign of correct
needle placement when performing
a caudal block in pediatric patients.
Anesthesia and Analgesia 1994; 79: 818.
6 Adewale L, Dearlove O, Wilson B,
Hindle K, Robinson DN. The caudal
canal in children: a study using mag-
netic resonance imaging. Paediatric
Anaesthesia 2000; 10: 137–41.
Use of mini Doppler for arterialcannulation
The following case illustrates how a
mini Doppler can be useful in helping
arterial cannulation in some situations.
A 77-year-old female patient was
admitted to our ITU following a
laparotomy for revision of Hartmann’s,
repair of entero-cutaneous fistula and
drainage of pelvic abscess. She was
previously admitted to the ITU follow-
ing laparotomy for multiple sigmoid
perforations and peritonitis. During the
previous admission, she suffered multi
organ failure and took approximately
3 weeks before she was discharged to
the ward; she was very oedematous on
discharge. During the following weeks,
she became very unwell and her wound
broke down and she was suspected of
having an abdominal abscess. She was
taken to theatre for another laparotomy
as the only option left. She was anaes-
thetised and a triple lumen was sited in
her right internal jugular vein with no
success at arterial cannulation. She was
then transferred to ITU for further
management. She was sedated and ven-
tilated and required minimal inotropic
support.
On admission to ITU, arterial cann-
ulation was attempted and was difficult
as arterial pulsations were either absent
or feeble and made worse by the
oedema on top of her obesity, after
an hour of struggling, we managed to
cannulate the left brachial artery,
which lasted for only a couple of
hours. At this stage, I borrowed a
Mini Doppler D 500 (Huntleigh Tech-
nologies) from the surgical ward. Using
an 8 Mz probe, I found the flow in the
right radial artery and after eliciting a
maximum flow signal made impres-
sions proximally in the oedematous
arm along the path of the artery. Using
a 20 G arterial cannula and following
the direction of the artery, I was able
to cannulate it at the first attempt and
on transducing showed a good arterial
waveform that lasted for a few days.
The research literature indicates that
Doppler ultrasound has been used to
cannulate radial arteries in mostly the
paediatric age group and occasionally
in adults. The mini Doppler has been
shown to be a useful tool when faced
with a patient similar to ours who is
obese, oedematous and with previous
admission to ITU.
R. K. Kota
Queen Elizabeth II Hospital,
Welwyn Garden City, AL7 4HQ, UK
E-mail: [email protected]
The eye of a pregnant womanand obstetric anaesthesia
Despite success with contact lenses
prior to pregnancy, some women
may develop contact lens intolerance
when pregnant [1]. Anaesthetists cause
damage to the eye by not protecting it
peri-operatively [2]. I herein report a
case of a healthy parturient who
developed bilateral corneal photosensi-
tivity and foreign body sensation after
an uneventful Caesarean section under
general anaesthesia. These symptoms
were initially believed to result from
peri-operative corneal damage. How-
ever, consultation with an ophthalm-
ologist established the diagnosis of
pregnancy-related contact lens intoler-
ance.
A 26-year-old, gravida 2, para 1,
otherwise healthy female (specifically
pre eclampsia and diabetes were not
present) with a history of myopia (cor-
rected with contact lenses), at 39 weeks
gestation required an emergent Caesar-
ean section for fetal distress, which was
conducted under general anaesthesia.
The surgery and anaesthesia were
uneventful. Her contact lenses had been
removed pre-operatively in the holding
area. After induction of anaesthesia,
both eyes were lubricated with sterile
lubricant ophthalmic ointment (Tears
Renewed, Akorn, Inc., Buffalo Grove,
IL 60089, USA), and intra-operatively
remained taped in a standard manner.
Two hours after the surgery end, the
patient reported bilateral eye tearing,
photophobia, and decreased visual acu-
ity (at that time her contact lenses were
back in place). The possibility that her
eyes had been damaged peri-operatively
was entertained (although bilateral
symptomatology seemed puzzling for
the presumed aetiology) and ophthal-
mology consultation was requested. No
damage to her eyes was found and the
patient admitted to fitting new contact
lenses.
Visual disturbances are not uncom-
mon among pregnant women [1].
Although some ocular changes associ-
ated with pregnancy may offer insight
into the pathophysiology of a pregnancy
specific (e.g. pre eclampsia) or non-
pregnancy specific (e.g. diabetes, glau-
coma) disease, many visual changes in a
parturient are of a benign nature, war-
rant no ophthalmic referral and require
no treatment. Weinreb et al. measured
the corneal thickness in 89 pregnant
women and found an increase by about
3% in comparison to the control group
of non-pregnant women [3]. The
increase was attributed to increased
water retention during pregnancy. Park
et al. followed 24 women throughout
pregnancy and found an increase in the
corneal curvature during the second and
third trimesters [4]. The curvature
either resolved postpartum or after the
cessation of breast-feeding. The preg-
nancy-related contact lens intolerance is
unlikely to be due to an increase in
corneal sensitivity. Conversely, corneal
sensitivity either does not change [4] or
decreases in pregnancy, possibly relating
to water retention [5]. The intolerance
may actually be due to an increase in
either corneal curvature or thickness
associated with pregnancy [3,4]. These
findings have led to the recommenda-
tions that pregnant women should delay
fitting new contact lenses until several
weeks postpartum.
Anaesthetised patients in an operating
room environment are at risk for inci-
dental trauma to the eye related to
positioning, non-surgical manipulation,
and equipment. The most common
ocular complication of general anaes-
thesia is corneal abrasion caused by the
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1142 � 2003 Blackwell Publishing Ltd
mask or surgical drapes [1]. Corneal
injury caused by drying or inadvertent
eye injury, often presents during recov-
ery with tearing, decreased visual acuity,
pain and photophobia. An immediate
consultation with an ophthalmologist is
indicated. Abrasion is diagnosed with
fluoroscein staining and usually heals
spontaneously over 24–48 h, leaving no
permanent damage. Treatment with
application of artificial tears and eye
closure is primarily symptomatic.
The author of this letter is not aware
of any other reports documenting the
occurrence of new onset pregnancy-
related contact lens intolerance in the
immediate post anaesthesia period. In
conclusion, this case report should alert
the anaesthetist that temporal associ-
ation of ocular complications with
general anaesthesia might falsely suggest
anaesthesia-related eye injury.
K. M. Kuczkowski
UCSD Medical Center,
San Diego, CA 92103–8770, USA
E-mail: [email protected]
References1 Dinn RB, Harris A, Marcus PS.
Ocular changes in pregnancy. Obstet-
rics and Gynecology Survey 2003; 58:
137–44.
2 Grover VK, Kumar KV, Sharma S,
Sethi N, Grewal SP. Comparison of
methods of eye protection under
general anaesthesia. Canadian Journal of
Anaesthesia 1998; 45: 575–7.
3 Weinreb RN, Lu A, Beeson C.
Maternal corneal thickness during
pregnancy. American Journal of Oph-
thalmology 1988; 105: 258–60.
4 Park SB, Lindahl KJ, Temnycky GO,
Aquavella JV. The effect of pregnancy
on corneal curvature. CLAO Journal
1992; 18: 256–9.
5 Riss B, Riss P. Corneal sensitivity in
pregnancy. Ophthalmologica 1981; 183:
57–62.
A novel use for the ProSeallaryngeal mask
We would like to report a novel use of
the ProSeal laryngeal mask airway.
The patient was a 65-year-old,
72 kg, ASA 3 male with a history of
cardiac disease, scheduled for elective
laparoscopic cholecystectomy [1].
Following induction with propofol
and fentanyl, the ProSeal laryngeal
mask was inserted in the normal way.
A nasogastric tube was inserted via the
drainage port and the stomach was
aspirated. After pneumoperitoneum
was established, the nasogastric tube
was withdrawn and a Deltex oesopha-
geal Doppler probe inserted. The
probe was easy to introduce using
water-based lubrication jelly. The first
depth marker was moved up to the
level of the second marker to allow the
probe to fit comfortably in the port
(Fig. 6). The probe was focused and
cardiac output parameters obtained: the
trace remained steady as the Doppler
probe was held firmly in position in
the port. Following removal of the
Doppler probe, the nasogastric tube
was reinserted to empty the stomach
prior to emergence from anaesthesia.
We would recommend the use of the
oesophageal Doppler in the ProSeal
laryngeal mask for high-risk patients
[2] where intubation is not required.
S. Green
M. Soskin
West Hertfordshire Hospitals, UK
E-mail: stupen@greenwil.
freeserve.co.uk
References1 Maltby JR, Beriault MT, Watson
NC, Liepert D, Fick GH. The
LMA-ProSeal is an effective alter-
native to tracheal intubation for
laparoscopic cholecystectomy.
Canadian Journal of Anaesthesia 2002;
49: 857–62.
2 Haxby EJ, Gray MR, Rodriguez C,
Nott D, Springall M, Mythen M.
Assessment of cardiovascular changes
during laparoscopic hernia repair using
oesophageal Doppler. British Journal of
Anaesthesia 1997; 78: 515–19.
Radiographic guided epiduralplacement
We write in support of the recently
reported observations (Johnson et al.
Anaesthesia 2003; 58: 485–6) that fluo-
roscopic guidance of placement of epi-
dural catheters offers advantages over
traditional methods. We have been using
fluoroscopic guidance for epidural cath-
eter placement in our clinic for more
than 10 years. While the catheters are
generally placed for treatment of chronic
pain conditions such as back pain, arm or
leg pain, we have also done a number for
patients with cancer pain, and a number
for acute pain problems such as fractured
ribs or fractured sternum. On request of
our anaesthetic colleagues, we have
occasionally placed epidural catheters
pre-operatively under fluoroscopic guid-
ance for use for postoperative pain.
From 1999 to 2003 we placed 78
epidural catheters under fluoroscopic
guidance, five in the cervical, 12 in the
thoracic and the remainder in the lum-
bar epidural space. In our experience,
fluoroscopic guided epidural placement
is quick, simple and safe. We have the
advantage, however, of having routine
lists with fluoroscopy available and can
simply add patients on to this twice a
week list as required. Placement of
epidural catheters under fluoroscopy
can be done in just a matter of minutes
and does not add substantially to the
time of placement compared to tradi-
tional techniques. Catheters are placed
with the patients awake but under
sedation and lying prone, which pro-
vides a stable platform for performance
of the technique.
There are many advantages in fluoro-
scopic guidance. Catheters can be placed
accurately at the site of the appropriate
dermatome. Catheters can be placed
selectively either on the right or left side
of the spine. This is true in both the
lumbar and cervical epidural space but it
is more difficult to get lateral placement
in the thoracic spine because the gap in
the lamina where the needle needs to be
Figure 6
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1143
placed is narrower. Unilateral catheter
placement is easily obtained and is ideal
for unilateral pain. Fluoroscopic guid-
ance may provide greater safety, as using
a lateral view gives a clear indication of
exactly where the needle is at all times.
After loss of resistance to saline, con-
trast (Isovist 240 mg.ml)1, 0.5 ml) is
injected through the Tuohy needle to
confirm that it is in the epidural space.
The epidural catheter is then advanced
into the epidural space to the 20 cm
mark; this leaves anywhere between 10
and 15 cm of catheter in the epidural
space. This is substantially greater than
is traditionally used in anaesthetic or
obstetric practice. Contrast (0.5–1.0 ml)
is then injected down the catheter and
the exact position of the tip determined.
If the catheter is not in the correct place
or on the correct side, it can be readily
repositioned. The main concern anaes-
thetists have about putting excessive
catheter in the epidural space is that the
catheter may migrate through the inter-
vertebral foramen. In our experience this
is unusual occurring in 1–2% of patients.
Catheter migration is easily rectified by
repositioning the catheter and then
injecting more contrast to make sure
that the catheter is in the correct place.
We have found that inserting excess
catheter prevents it falling out.
We support the use of fluoroscopic
guidance for placement of epidural
catheters in situations where epidural
analgesia is important postoperatively or
where spinal anatomy may present a
particular challenge. Screening may be
relatively easily obtained by liaison with
Pain Clinic colleagues.
M. Khan
S. J. Dolin
St Richard’s Hospital,
Chichester PO19 6SE, UK
E-mail: [email protected]
References1 Wildsmith JAW, Fischer HBJ,
Gruning T. Regional Anaesthesia
before or after general anaesthesia?
Anaesthesia 1999; 54: 86–7.
2 Johnson TW, Morgan E, Smally P.
Radiographic guided epidural place-
ment. Anaesthesia 2003; 58: 485–6.
3 Picard J. Awake or asleep. Anaesthesia
2002; 57: 1233.
The management ofsuccinylcholine apnoea
The more I read the letter concerning
the treatment of succinylcholine apnoea
(Dahas & Vohra. Anaesthesia 2003; 58:
815–6), the more concerned I became. I
remembered well the teaching I recei-
ved as a junior that succinylcholine
apnoea never killed anybody but atte-
mpts to treat it might.
Can I remind readers of the case
report by Vickers written some 40 years
ago entitled �The mismanagement of
succinylcholine apnoea�? [1] He, too,
tried several doses of neostigmine, pro-
longing the patient’s eventual recovery.
He commented: �Adequate patience is
the best and least toxic therapeutic
agent, although the use of fresh plasma,
or blood, would be likely to terminate
the apnoea.� Vickers was writing in the
days before blood-borne virus infec-
tions came to the fore.
I wonder if our present authors really
believe that a proven risk of 1 in
220 000 of contracting HIV or viral
hepatitis is a price worth paying for the
accelerated conclusion of a self-limiting
condition? Are they confident that all
the infectious agents in donor blood
have now been discovered?
I. Barker
Sheffield Children’s Hospital,
Sheffield S10 2TH, UK
Reference1 Vickers MDA. The mismanagement of
Suxamethonium Apnoea. British Journal
of Anaesthesia 1963; 35: 260–8.
Scavenging malfunction
Scavenging is an essential component
of anaesthetic machines, and its pres-
ence and function should be con-
firmed as part of the routine preuse
check of anaesthetic equipment, in
accordance with AAGBI guidelines
[1]. As the function of the scavenging
system is to vent waste gases away
from the patient breathing circuit, the
performance of these two systems is
closely related.
An anaesthetised patient was connec-
ted to a previously checked anaesthetic
machine when the reservoir bag was
heard to collapse. Inspection confirmed
it was completely empty and not mov-
ing. The patient’s chest movement and
observations were all satisfactory and
there was no leak or disconnection of
the breathing circuit. The flow meters
were unchanged. Activation of the
oxygen flush did not refill the reservoir
bag. The capnograph trace and meas-
ured gas concentrations in the breathing
circuit started to decrease.
The scavenging unit (AGSS) was
suspected as the cause of this problem,
emptying the circuit by venting all gas
flow. This was tested by disconnecting
the scavenging pipe from the wall socket,
which resulted in the reservoir bag
refilling and the return of all measured
gas parameters to normal. The patient
was unharmed by this incident, and the
case was completed with the scavenging
disconnected and waste gases vented out
of the window via �elephant tubing�.Investigation revealed the absence of
the grille attachment from the bottom
of the scavenging unit (Fig. 7), which
is used on this unit to filter out dust
and debris. This had allowed the build
up of dust and particulate matter
within the scavenging system, which
had reached a critical point sufficient to
affect the function of the unit (personal
communication: Mr B Bailey, Hospital
Engineer).
Figure 7 AGSS scavenging unit.
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1144 � 2003 Blackwell Publishing Ltd
Increasing the negative pressure in
the scavenging system will cause vent-
ing of increasing amounts of gas. When
this reaches a critical point, the entire
fresh gas flow is vented through the
scavenging with none going to the
patient as in this case.
This incident highlights the need to
be familiar with the components and
function of this essential piece of equip-
ment in order that potential hazards can
be identified.
J. S. Gray
G. A. Evans
Walsgrave Hospital,
Coventry CV2 2DX, UK
E-mail: [email protected]
Reference1 The Association of Anaesthetists of
Great Britain and Ireland. Checklist for
anaesthetic apparatus 1997.
A comparison of simulateddifficult intubation withmultiple-use and single-usebougies
The authors (Annamaneni et al. Anaes-
thesia 2003; 58: 45–9) are to be com-
plimented on an ingenious and elegant
investigation into the efficacy of single-
use bougies. Whilst we are extremely
sympathetic to the conclusions of the
authors, we have noticed a minor flaw
in the design of their study in that
the grade 3 laryngoscopic view was
achieved whilst the manikin was not in
the �sniffing-the-morning-air� position.
This may or may not have biased the
results against the single-use bougie.
The �sniffing-the-morning-air� posi-
tion is designed to align the oral,
pharyngeal and laryngeal axes as closely
as possible to a straight line. Figure 8
illustrates the various angles between
the different axes with the head and
neck in a �neutral� position. Whilst the
laryngeal and pharyngeal axes are in a
relatively good alignment, there is an
almost perpendicular angle between the
pharyngeal and oral axes. Whilst
extending the neck will improve the
angle between the pharyngeal and the
oral axes, it exacerbates the angle
between the pharynx and the larynx
(Fig. 9). It is only the addition of a
pillow, with the neck extended, that
brings all three axes into alignment with
each other (Fig. 10).
The second experiment described by
the authors demonstrates the inferior
ability of the single-use bougie to
maintain its curvature once so posi-
tioned. Clearly, this is of paramount
importance whilst trying to negotiate
the perpendicular bend between the
pharyngeal and oral axes caused by the
omission of the pillow; however, you
may �just about get away with� a
straighter bougie when there is better
alignment of the three axes once the
pillow is employed.
We do not believe that anyone with
clinical experience of both bougies
would prefer the single-use over the
multiple-use bougie. Nonetheless, there
is a possibility that the single-use bougie
is not as inferior as suggested by this
otherwise excellent study.
M. M. Lim
M. Pead
Royal London Hospital,
London E1 1BB, UK
E-mail: [email protected]
A replyThank you for giving us the opportunity
to reply and we thank Drs Lim and Pead
for their interest in our paper. In order to
produce the grade 3 laryngoscopic view
in our study, the head of the manikin was
positioned without a pillow and conse-
quently the axes were not optimally
aligned. However, the intubating con-
ditions for both bougies were the same.
The Laerdal Airway Management Trai-
ner was not designed to be used with a
pillow. We therefore believe that the
absence of the pillow did not bias our
results against the single use bougie.
We agree that the �sniffing the morn-
ing air� position is intended to align the
three axes and improve the laryngoscop-
ic view. Difficult laryngoscopy may be
caused by an inability to obtain appro-
priate axial alignment. The availability of
a device that will successfully negotiate
the curvature of the airway may be
crucial with a grade 3 view. We do not
support the view that �you may just
about get away with a straighter bougie�in grade 3 laryngoscopy when a pillow is
employed. In clinical practice, the pillow
is routinely employed, whereas the
manikin set up is designed to produce a
grade 3 view without a pillow.
Marfin et al. simulated grade-3a
laryngeal view (epiglottis only just
obscuring the view of the arytenoids)
Figure 8 Head and neck in neutral position.
Figure 10 Upper neck extended with head on
pillow. OA Oral Axis; PA Pharyngeal Axis; LA
Laryngeal Axis. Adapted from Miller RD.
Anaesthesia, 5th edn. Philadelphia: Churchill &
Livingstone, 2000.
Figure 9 Upper neck extended but head not
on pillow.
Anaesthesia, 2003, 58, pages 1119–1146 Correspondence......................................................................................................................................................................................................................
� 2003 Blackwell Publishing Ltd 1145
on patients by lowering the Macintosh
laryngoscope blade [1]. The multiple-
use bougie in the Marfin study was
successful in 15 ⁄ 16 (94%) cases and
the single-use bougie success rate was
9 ⁄ 16 (56%) cases. A pillow was pre-
sumably used in this study. Therefore,
even in aligned axes, a bougie that is
able to maintain the curve (multiple-
use) is much more likely to be
successful. We believe there was no
bias in the Marfin clinical study, which
produced similar results to our manikin
study. Both favoured the multiple-use
bougie.
The multiple use bougie is designed
to be used five times [2]. The Technical
Data sheet for the Eschmann Healthcare
Tracheal Tube Introducer (bougie) is,
however, very confusing. The first
symbol on the front page of the Tech-
nical Data sheet is a symbol for single use
device (a crossed out 2). The manufac-
turer claims that the symbols on the
front page are merely illustrative of their
meaning. Only with careful scrutiny of
the Description section on the second
page is it apparent that it is recommen-
ded that the device �can be re-used a
maximum of five times�. We believe that
the Technical Data sheet needs to be
urgently changed to illustrate clearly that
it is a multiple-use device. We are aware
of number of colleagues who errone-
ously presumed on the basis of reading
the Technical Data sheet that it was
recommended that the device should be
used once only.
A number of multiple-use devices
such as the laryngeal mask, laryngoscope
blade and fibreoptic scope are widely
used in routine anaesthetic practice. It
does not seem logical to support the use
of an inferior and potentially dangerous
single-use bougie in the management of
difficult intubation. Some departments
are currently using single-use bougies
only. Other departments are using
multiple-use bougies a variable number
of times. Some departments are using
multiple-use bougie but only once. If all
departments adopted this latter strategy
shortages would quickly become appar-
ent because the supply of the multiple-
use bougie is limited by the complexity
of the manufacturing process. It appears
that confusion reigns.
The manufacturer has never released
the data justifying the maximum num-
ber of uses. The maximum five times
use was based on the fact that cracks
appeared in the varnish of �some� bou-
gies after 10 cycles of disinfection. For
the sake of safety, the number of uses
was arbitrarily halved to five (C Russell
personal communication). Test details
have, however, never been released and
may need to be reviewed.
An alternative strategy would be to
use a multiple-use bougie more than
five times after examining it carefully
for cracks before use [3,4]. Variation of
this strategy has been used by numerous
departments for many years. It appears
accurate records of the number of uses
are not kept by many departments.
At the moment, we do not have
available a suitably tested single-use
device. We believe that under these
circumstances, the use of the long
established Eschmann Introducer should
not be abandoned.
The single-use bougie performed
poorly in both in-vivo and in-vitro
studies. Therefore, the conclusion of
our manikin study is that the single-use
bougie is an inferior alternative to the
multiple-use bougie when intubating in
a grade 3 laryngoscopic view. Since it is
also likely to be more traumatic [5], we
believe that this device should no longer
be used.
I. Hodzovic
R. Annamaneni
A. R. Wilkes
I. P. Latto
University Hospital of Wales,
Cardiff CF14 0RA, UK
References1 Marfin AG, Hames KC, Pandit JJ,
Popat MT. Comparison of single-use
plastic bougie and multiple-use gum
elastic bougie for tracheal intubation in
simulated grade III difficult intubation.
Anaesthesia 2003; 58: 511–12.
2 Technical Data sheet Eschmann
Healthcare Tracheal Tube Introducer
SIMS, Portex, Hythe Kent.
3 Robins PM. Critical incident with gum
elastic bougie. Anaesthesia and Intensive
Care 1995; 23: 654.
4 Latto IP. Fracture of the outer
varnish layer of a gum elastic bougie.
Anaesthesia 1999; 54: 497–8.
5 Wilkes AR, Hodzovic I, Latto IP.
Comparison of the peak forces
that can be exerted by multiple-use
and single-use bougies in vitro.
British Journal of Anaesthesia 2002;
89: 671.
Correspondence Anaesthesia, 2003, 58, pages 1119–1146......................................................................................................................................................................................................................
1146 � 2003 Blackwell Publishing Ltd