Managing accidentally cut epidural catheters

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


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


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......................................................................................................................................................................................................................


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


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).



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)



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


References1 Fay A, Abinun M. Current manage-

ment of hereditary angio-oedema

(C1 esterase inhibitor deficiency).



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


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.



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.



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


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



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


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


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



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



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


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



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


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


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



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


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



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


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


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?


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



(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


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



lifesaving in some difficult airway

scenarios.

M. Al Shamaa

P. Jefferson

D. R. Ball

Dumfries and Galloway Royal

Infirmary,

Dumfries DG1 4AP, UK


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,



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


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.


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.



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


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


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)



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


References1 Kapila A, Glass P, Jacobs JR, et al.

Measured context sensitive half

times of remifentanil and alfentanil.


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



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


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


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


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



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.


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



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


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


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



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


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



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


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



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


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.



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


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


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.



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.



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