PREDICTING THE AIRWAY CHANGES DURING THE

COURSE OF PREGNANCY, LABOUR AND AFTER

DELIVERY USING MALLAMPATI CLASSIFICATION

AMONG INDIAN WOMEN – A PROSPECTIVE

OBSERVATIONAL STUDY.

Dissertation submitted to the Tamil Nadu Dr.M.G.R Medical University in

partial fulfilment of the rules and regulations for MD Degree examination in

Anaesthesiology to be held in April 2017.

Dr. JAYAPRAKASH ARUNACHALAM

DEPARTMENT OF ANAESTHESIOLOGY,

PSG INSTITUTE OF MEDICAL SCIENCES AND RESEARCH,

COIMBATORE 641004.

TAMIL NADU, INDIA

CERTIFICATE

CERTIFICATE

This is to certify that Dr. JAYAPRAKASH ARUNACHALAM a post

graduate student (2014-2017) in the Department of Anaesthesiology, PSG

Institute of Medical Sciences & Research, Coimbatore has done this dissertation

titled "PREDICTING THE AIRWAY CHANGES DURING THE COURSE

OF PREGNANCY, LABOUR AND AFTER DELIVERY USING

MALLAMPATI CLASSIFICATION AMONG INDIAN WOMEN." under

the direct guidance and supervision of guide Prof. Dr.C.GANESAN in partial

fulfillment of the regulations laid down by the Tamilnadu Dr.M.G.R. Medical

University.

Prof. Dr. C. GANESAN MD,DNB, PDCCA Prof. Dr. RAMALINGAM MD

HEAD OF THE DEPARTMENT PRINCIPAL

DEPARTMENT OF ANAESTHESIOLOGY PSGIMS&R

PSGIMS&R

CERTIFICATE BY THE GUIDE

This is to certify that Dr. JAYAPRAKASH ARUNACHALAM a post

graduate student (2014-2017) in the Department of Anaesthesiology, PSG

Institute of Medical Sciences & Research, Coimbatore has done this dissertation

titled "PREDICTING THE AIRWAY CHANGES DURING THE COURSE

OF PREGNANCY, LABOUR AND AFTER DELIVERY USING

MALLAMPATI CLASSIFICATION AMONG INDIAN WOMEN." under

the direct guidance and supervision of guide Prof. Dr.C.GANESAN in partial

fulfillment of the regulations laid down by the Tamilnadu Dr.M.G.R. Medical

University.

Prof. Dr. C. GANESAN MD,DNB, PDCCA

HEAD OF THE DEPARTMENT

DEPARTMENT OF ANAESTHESIOLOGY

PSGIMS&R

DECLARATION

DECLARATION

I hereby declare that this dissertation entitled "PREDICTING THE

AIRWAY CHANGES DURING THE COURSE OF PREGNANCY,

LABOUR AND AFTER DELIVERY USING MALLAMPATI

CLASSIFICATION AMONG INDIAN WOMEN" was prepared by me under

the direct guidance and supervision of Prof. Dr. C. GANESAN, PSG Hospitals,

Coimbatore.

This dissertation is submitted to the Dr.M.G.R Medical university in

partial fulfillment of the university regulations for the award of MD degree in

Anaesthesiology, Examination to be held in April 2017.

PLACE: Coimbatore Dr. JAYAPRAKASH ARUNACHALAM

DATE:

ACKNOWLEDGEMENT

ACKNOWLEDGEMENTS

At the outset I am extremely indebted to the Department of

Anaesthesiology, PSGIMS&R, Coimbatore and the Institutional Human Ethics

Committee for permitting me to carry out this thesis.

I am fortunate enough to do research with the scholarly supervision of

Professor and Head of the department Dr.C.GANESAN. His words of

encouragement, academic discussions and valuable guidance have enabled me in

completing this thesis. But for his good sense and large hearted forbearance I

would not have completed it. His contribution is visible in the outcome of this

thesis. So I record my heartfelt gratitude and indebtedness to him.

I take this opportunity to express my gratitude to Professor Dr.SEETHA

PANICKER, Head of the Department of Obstetrics and Gynaecology and other

members for providing me all facilities to undertake this research work.

It is my privilege to express my thankfulness to my revered teachers and

my colleagues of my department for helping me at various stages to complete

this thesis.

Though it is like thanking myself, my heartfelt gratitude always goes to

my parents Dr. R. Arunachalam and Dr.P.Amirtha Rani Manimekalai and

memebers of my family who shape my life with utmost care and affection.

Last but not the least I am thankful to the patients who cooperated with

me in this study for survey and Dr .S. Preethi, Post graduate, Department of

Community Medicine, Yenopaya Medical College, Mangalore for her timely

statistical assistance.

Dr. JAYAPRAKASH ARUNACHALAM

LIST OF ABBREVATIONS

ASA : AMERICAN SOCIETY OF ANAESTHESIOLOGISTS

BMI : BODY MASS INDEX

Cms : CENTIMETRES

IV : INTRAVENOUS

IV 1 : INTRAVENOUS FLUIDS GIVEN DURING FIRST

STAGE OF LABOUR

MP : MALLAMPATI

MPC : MALLAMPATI CLASSIFICATION

MP I : MALLAMPATI CLASS AT FIRST TIME INTERVAL

MP II : MALLAMPATI CLASS AT SECOND TIME INTERVAL

MP III : MALLAMPATI CLASS AT THIRD TIME INTERVAL

MP IV : MALLAMPATI CLASS AT FOURTH TIME INTERVAL

TMD : THYROMENTAL DISTANCE

TMJ : TEMPOROMANDIBULAR JOINT

VC : VOCAL CORDS

INDEX

CONTENT PAGE NO.

1) INTRODUCTON 1

2) AIMS OF THE STUDY 3

3) OBJECTIVES OF THE STUDY 4

4) REVIEW OF LITERATURE 5

5) METHODOLOGY 42

6) RESULTS 46

7) DISSCUSSION 76

8) CONCLUSION 81

9) BIBLIOGRAPHY

10) ANNEXURE

INTRODUCTION

1

INTRODUCTION

Ability to predict a difficult airway aids in conducting anaesthesia safely

and effectively by keeping all the equipment and personnel ready. A difficulty in

airway management in patients is highly stressful for an anaesthetist and

especially in obstetrics patients it is even more catastrophic1-4

.

In obstetrical anaesthesia the risk associated with difficult airway leading

to failed tracheal intubation which finally causes anaesthesia related deaths are

high. It is said that obstetric patients carry 8 times more risk than normal

population for failed intubation5.

Difficult tracheal intubation during induction of general

anaesthesia for obstetric patients remains the major contributing factor to

anaesthesia related obstetric complications. A proper preoperative evaluation is

required to anticipate and be prepared for these situations. It is also very

important to have knowledge about the factors which are more associated with

these airway changes in obstetric patients so an anaesthesiologist can have all the

equipment ready before hand and handle the situation seamlessly thereby

improving the safety of pregnant patients5.

A variety of examinations and measures are used to predict difficult

airway including Mouth opening, range of neck movements, thyromental

distance, sternomental distance etc. Mallampati classification of airway with

2

Samsoon modification is a bedside test to asses difficulty of airway by looking at

the oropharyngeal structures.

This test is universally accepted and highly specific bedside test for

assessing airway difficulty. We have used this test in our study because of its

convenience to the patient and a very good tool to assess the airway difficulty.

Numbers of studies have proven that there are changes in airway during

pregnancy and labour. These changes are mostly soft tissue changes such as

airway oedema which can increase in pregnancy which can be examined using

Mallampati classification. Studies have also suggested that airway of pregnant

women change along the course of pregnancy and labour because of various

physiological changes such as weight gain, airway oedema etc.

However there are very few studies that has suggested about the

predicting factors causing these airway changes in pregnant women. There are

many factors such as fluids administered during labour, duration of labour which

plays an important role in changing difficulty in airway along the course of the

pregnancy and labour. There are very few studies that actually correlate with

these factors.

Keeping this in mind we evaluated the changes along the course of

pregnancy and labour and even predicting factors that are more likely to cause

these airway changes in pregnant women.

AIMS OF THE STUDY

3

AIMS OF THE STUDY

To study the incidence of changes in the airway during course of

pregnancy, labour and after delivery and to predict the factors that are influential

in causing these changes.

OBJECTIVES

4

OBJECTIVES OF THE STUDY

PRIMARY OBJECTIVE

To predict the factors causing airway changes during the course of

pregnancy, labour and delivery so that an anaesthesiologist can anticipate the

difficulty beforehand and provide safer anaesthesia.

SECONDARY OBJECTIVE

To conduct a study of this kind in Indian population as all previous

studies pertaining to this topic have been done only in western population.

REVIEW OF LITERATURE

5

REVIEW OF LITERATURE

An anaesthesiologist has many responsibilities, one of the most prime

responsibilities is to secure and maintain a patent airway. Failure in doing so can

result in catastrophic events or even death6. In a study conducted by Samsoon

GL et.al. which was a retrospective study of more than 15000 patients, it was

found out that every 1 out of 2230 in general surgical patients and every 1 out of

283 in obstetric patients had a failed intubation7. So it is noted that obstetric

patients are at 8 times more risk than general surgical population for a failed

intubation.

In the meta-analysis conducted by Shiga et al that included 35 studies

with 50,760 patients the incidence of difficult intubation was 5.8% for overall

population8.

CLINICAL PRACTICE PRINCIPLES OF TRACHEAL INTUBATION

There are four principles which help in preventing complications9

Maintaining oxygenation- this is the top priority. Preoxygenation should

be done and practised regularly before induction of anaesthesia. It is better to

prevent trauma and first attempt is always the best attempt.

Equipment for difficult airway should be kept ready if any difficulty is

suspected. Call for help as soon as possible if any difficulty in tracheal

intubation is encountered.

6

INDICATIONS FOR TRACHEAL INTUBATION10

:

SURGICAL AND ANAESTHETIC –

Providing general anaesthesia.

Requirement of neuromuscular blockade for surgical procedures such

as abdominal surgeries.

Surgeries in which airway is shared such as ENT surgeries.

Patients who are at high risk for aspiration of gastric contents such as

upper GI obstruction, sepsis, trauma.

Prolonged surgery.

Surgeries that impair gas exchange.

CRITICAL ILLNESS-

Poor or impaired respiratory function leading to hypoxia/hypercarbia

which does not respond to non-invasive ventilation.

Airway protection in patients who are unable to protect their airway such

as comatose patients.

Prevention of increase in ICP in TBI patients.

7

AIRWAY ANATOMY

An anaesthesiologist should be aware of the anatomy of airway as it helps

in securing the airway without any complications11

NOSE-

It has two parts which includes external nose and internal nasal cavity.

Cribriform plate forms the roof of nasal cavity. The lateral wall is formed by

three bony turbinates. Para nasal sinuses drain into the lateral wall. The

anaesthetic consideration is

1. Nose helps in humidification of air.

2. Nasal mucosal lining is very friable and highly vascular so nasal

decongestants prior to any procedure will help in decreasing the bleeding.

3. Cribriform plate damage can cause a communication between nasal

cavity and intracranial cavity which can lead to meningitis.

FIGURE 1- ANATOMY OF THE NOSE

8

ORAL CAVITY

Hard palate and soft palate forms roof of oral cavity

Floor of the oral cavity is made up of tongue which on either side is

bounded by teeth. The posterior part of the tongue is bounded by the lingual

tonsil. Importance to anaesthetist is that if the lingual tonsil is hypertrophied can

cause difficulty on working space.

FIGURE 2- ANATOMY OF THE ORAL CAVITY

9

PHARYNX-

It is a fibro muscular tube which extends from the skull base to the

cricoid cartilages. The upper part communicates with oral cavity and nose and

lower part communicates with the oesophagus and larynx. Anaesthetic

implications are that any blind attempt of intubation can cause trauma of

pharyngeal structures and can cause bleeding and any application of greater

force can cause sub mucosal passage of the tube.

FIGURE 3- ANATOMY OF PHARYNX

10

LARYNX-

Cartilaginous structure which extends from the epiglottis to the cricoid

cartilages. It consists of cartilages which are supported by the ligaments and

muscles.

Three paired cartilages are arytenoid, cuneiform and corniculate and three

unpaired are cricoid, thyroid and epiglottis.

The laryngeal inlet is surrounded by aryepiglottic folds, epiglottis,

posterior cartilage and inter arytenoid notches. The vocal cords are attached to

the vocal process of thyroid and arytenoid cartilages. Valleculae are space

between median and lateral glossoepiglottic folds.

Importance – while performing laryngoscopy the macintosh blade is

inserted and placed into valleculae where it tenses the epiglottic ligament and it

causes elevation of the larynx.

11

FIGURE 4- ANATOMY OF LARYNX

FIGURE 5- ANATOMY OF VOCAL CORDS

12

TRACHEA

Cartilaginous structure which extends from the cricoid cartilages to the

carina. It consists of U shaped cartilaginous rings joined by trachealis muscle

and fibroelastic tissue.

FIGURE 6- ANATOMY OF TRACHEA

13

ANATOMICAL AND PHYSIOLOGICAL FACTORS12

The factors both anatomically and physiologically that take place in

pregnancy place the pregnant woman at a bigger risk than nonpregnant woman.

ANATOMICAL FACTORS12

-

Anatomical factors that place the pregnant woman at increased risks

include

1) Pregnancy-induced weight gain

2) Enlargements of breast

3) Respiratory system mucosal oedema

4) Pulmonary aspiration.

In supine position, the breasts fall back against the neck, which can

hinder both laryngoscopy and intubation.

Certain features that are present in the non-obstetric population include

total dentition, tiny mandible, restricted mouth opening, small neck, arched

palate can cause more difficulty in airway for anaesthesiologist. Several

disorders which have systemic involvement such as diabetes milletus which can

cause of glycosalation of ligaments, rheumatoid arthritis which can cause stiff

joints, sarcoidosis, and any swellings such as tumours involving the neck can

make it difficult to produce neck extension or even make it difficulty in opening

the mouth in the obstetric patient.

14

The diaphragm can be pushed above due to an increase due to enlarged

uterus at later stages in the pregnancy can cause anatomical difficulty. Moreover,

a hip wedge that is positioned incorrectly which can result in thoracic lift effect,

improperly applied cricoid pressure due to improper explanation by the

anaesthetist to the technician, lighter planes of anaesthesia due to reduced dosage

of neuromuscular blocking drugs and less opiods due to its effect on the foetus

which is common in obstetric anaesthesia during anaesthesia can also cause

difficulty in securing an airway in obstetric population. Proper education and

preparation can help us in reducing most of the adverse events associated with

difficult airway.

PHYSIOLOGICAL CHANGES12

-

Physiological changes associated with pregnancy are well known. These

physiological changes along with the anatomical changes which are already

discussed can cause severe consequences in difficult airway in obstetric

population.

Due to increase in foetal requirements a pregnant women has higher

oxygen demand and consumption to meet the foetal demands. Approximately

the oxygen consumption is 20% to 25% in pregnant women and this is achieved

by increase in respiratory rate and work of breathing. As the diaphragm is

pushed upwards in pregnancy the compliance of the chest wall is decreased

causing increase in airway pressure and basal atelectasis.

15

Due to these changes there is decrease in functional residual capacity

causing a fall in oxygen reserve which can lead to rapid desaturation during even

a small episode of apnoea can lead to hypoxic brain injury. However closing

capacity remains normal which can result in decrease of FRC/CC ratio and it

leads to closure of smaller airways than in patients with normal functional

residual capacity. When there is airway closure at normal tidal volume it will

increase in when patient is put in supine position and also the pulmonary shunt

fraction or the blood that is shunted from the pulmonary circulation which does

not take place in gas exchange increases and these patients are more prone for

hypoxemia.

Certain factors such as patients who are started on magnesium sulphate

therapy for severe pre eclampsia or for pre-term labour and patients who are on

narcotics for labour analgesia and patients with neuromuscular disorders such as

myasthenia gravis are more prone to have a profound decrease in minute

ventilation which can lead to hypoxemia or hypercapnia. This can manifest as

dangerous situations in clinical settings with patients more prone for very rapid

hypoxemia during induction of general anaesthesia.

To prevent these catastrophic events during induction of general

anaesthesia it is utmost importance to have a proper or patent airway that could

help us administering 100% oxygen to the patient. Positioning plays a major role

in oxygenating the patient before anaesthesia ,preferably a slightly head up

position helps in aligning three axis to help keep a patent airway and it helps in

16

increasing the functional residual capacity. Supine position in a pregnant woman

is dangerous as there is aortocaval compression causing decreased venous return

and that leads to hypotension by decreased cardiac output so it is better to keep a

slight left down tilt. This hypotension has been reported in 15-20% of the

patients.

Another dangerous complication in pregnant women is that they are at

increased risk for aspiration than the non-pregnant women are they are more

prone for aspiration of the contents in the stomach during induction of

anaesthesia. It occurs in almost 60% of the pregnant women at term . The reason

behind these affects are that they have increased amount of gastric acid secretion

which is also associated with decrease in pH of gastric acid along with laxity in

the sphincter action of gastroesophageal sphincter attributed to hormonal and

mechanical changes that occur in pregnancy.

The hormonal changes in the pregnancy include increased levels of

progesterone which decreases the gastric emptying and decreased pressure in the

lower oesophageal sphincter and placental gastrin hormone causes increase in

the gastric acid production and secretion. The changes become more prominent

such as to cause significant clinical effects only 12 weeks of pregnancy. The

gravid uterus attains a size to cause physical compression on stomach and it

causes to displace the stomach upwards causing pressure on the diaphragm and

also decreases the laxity of the gastroesophageal sphincter and causes more

chance of aspiration.

17

There are many other conditions in pregnancy that can cause increase in

gastric pressure such as twin gestation, lithotomy position and also

polyhydramnios. Fundal pressure applied during labour to push the foetus

downwards and help in delivery of the foetus cab increase the gastric pressure.

These are the reasons that place pregnant women at very high risk for aspiration

during general anaesthesia and it is recommended that all pregnant patients

coming for procedures that require general anaesthesia should receive anti

aspiration prophylaxis either pharmacologically or mechanically before

induction of general anaesthesia. Pharmacologically it is recommended to use

0.3 molar soidium citrate solution 25-30 ml which is non-particulate and should

be given at least 30 minutes prior to induction.

The main disadvantage associated with giving the sodium citrate is lesser

duration of action so it can‟t protect from the risk of aspiration during extubating

the patient post-surgery. To counter this problem associated with the sodium

citrate administration it is recommended to give an intravenous dosage of H2

receptor antagonist i.e. histamine receptor antagonist at least 45 minutes before

any manipulation of the airway. Cimetidine can cause severe hemodynamic

instability and can even lead to liver dysfunction so it is not being administered

anymore.

Ranitidine is the preferred drug of administration in these situations

because it is more safer and has no major hemodynamic disturbances and can

also be safely used in case of an emergency and another advantage of ranitidine

18

is that it has a duration of action of 4-6 hours so its action will help prevent

aspiration even during emergence from general anaesthesia. Proton pump

inhibitors are another class of drugs that can be used in decreasing gastric

secretions preoperatively. Omeprazole, a proton pump inhibitor is used

frequently and it takes at least 30-40 minutes to increase the pH of gastric

secretion. Metoclopramide is another agent used, it helps by prokinesis or by

increasing the motility of the gut to empty the gastric contents at a faster rate.

The main disadvantage is that is shown to cause extrapyramidal

symptoms in the mother and it can also the cross the placental barrier causing

neurobehavioral effects in the neonate as well. All these combination of drugs

discussed before are only useful and effective only if the patient has had a solid

diet recently before anaesthesia. Another method useful in these situations are

insertion of a nasogastric tube prior to induction and emptying out all the

contents and this method is useful if the pregnant woman is sedated in view of

labour analgesia. Although these methods have been carried out there is still a

risk of aspiration in pregnant population. Another method to decrease the risk of

aspiration in pregnant women is to apply cricoid pressure or Sellick‟s manoeuvre

during induction of anaesthesia.

In this method pressure applied on the cricoid cartilage compresses the

trachea downwards using the thumb and the middle finger and the aspiration is

reduced . Cricoid cartilage is preferred because it is a complete cartilaginous

structure and applying pressure on it can occlude the oesophagus preventing

19

aspiration of gastric contents properly. First the patient should be explained

about the cricoid pressure and cricoid pressure should be started at the beginning

of administration of induction agent, anaesthesiologist should ask for help of a

trained assistant and 15-20 newton of pressure should be applied on the cricoid

cartilage and the pressure should be sustained and only removed after

confirmation of position of the endotracheal tube by the anaesthesiologist.

Cricoid pressure application has been proved to reduce the incidence of

aspiration over the years and it has become a gold standard technique in

preventing aspiration in pregnant women or any patients with a full stomach

coming for general anaesthesia.

Another important factor in pregnancy that causes difficult airway in

pregnancy is that there is increase in total water composition of body leading to

fluid accumulation in mucosal membranes. The total body water composition in

pregnancy increases due to an increase in progesterone levels in the body and

also increased sodium and water retention due to over activity of the renin

aldosterone function in pregnancy.

The consequences of increased total body water can lead to fluid

accumulation in mucosal membranes causing oedema of the upper airway and

also larynx and vocal cords. This engorgement in addition to disorders such as

pre eclampsia, increased valasalva during strenuous labour and any respiratory

tract disorders can cause more oedema in airway in pregnant women causing

more difficult airway in pregnant women. Moreover, most of the patients receive

20

oxytocin during labour and an undesirable side effect of oxytocin is its

antidiuretic effect which leads to more fluid retention and causing fluid overload

and oedema which may result in decrease in working space of laryngoscopy

causing more chances of trauma and the friability of the mucosa in pregnancy

can lead to increased bleeding. Therefore, it is recommended to keep ready

smaller sized endotracheal tubes and agents which cause vasoconstriction of

mucosa with very little effect on uteroplacental vessels. Increase of tongue size

can make it problematic to draw back onto the mandibular space while

laryngoscopy. The weightiness increase that go with pregnancy is frequently 12

kg or more. Obesity has been told to extra increase risk of anaesthetic

complications in pregnant patients. An elevation in body mass index (BMI) has

been connected with an amplified risk of airway management complications

such as difficult intubation. [BMI is the weight in kilograms divided by height in

metres square. The ordinary BMI is 20-24.9; a BMI of 25-29.9 is overweight, a

BMI of 30-39.9 is obese, and a BMI more than 40 is morbidly obese. An

overweight patient weighs fewer than 20%-25% more than the expected IBW,

obese patient weigh up more than IBW (IDEAL BODY WEIGHT), and

morbidly obese patient weighs extra than twice of IBW. The breast increase that

escorts pregnancy is more prominent in the presence of disproportionate weight

gain. Intubation of these types of patients with engorged breasts is aided by the

use of a short or small handled laryngoscope and breast retraction. Good placing

of the patient aids intubation attempts and rises the likelihood of success.

Regional anaesthesia is also difficult to execute and extra-long needles should be

21

made available. Related variations in respiratory factors in adding to the

deviations due to pregnancy consist of, reduction in functional residual capacity,

total lung capacity and chest wall compliance. Additionally, there is increase in

the work of breathing because the contents in the abdominal cavity press against

the diaphragm and makes breathing difficult. Moreover, morbidly obese

pregnant women have a greater frequency of other obscuring medical conditions

such as diabetes mellitus and pregnancy induced hypertension.

Morbid obesity has been concerned as a causative factor in up to 75% of

anaesthesia associated maternal morbidity and mortality. Thus, assessment of

airway is of utmost importance. Measurement of oxygenation using oxygen

saturation in sitting and supine positions make available an early approach to

assess the grade of airway compromise and the possible for decline with more

decline in functional residual capacity. If general anaesthesia is “unavoidable”

and airway difficulty is expected, proper arranging of the patient with raised

shoulders by keeping folded towels under the occiput and place the head in

position like a sniffing position so that, the engorged breasts could be fallen off

from the neck providing more space for laryngoscopy. These tactics would

expose up the area that is lost in rolls of fat and allowing easy performance of

the laryngoscopy. In these kind of patients, the airway “gadgets” and substitute

methods of securing the airway become very important.

The bulk of pregnant women deliver without any need for airway and

ventilator support; nonetheless, when general anaesthesia is essential, the

22

changes both anatomically and physiologically that occur in pregnancy and

labour can add to difficulty with airway management thereby increasing the

threat of maternal morbidity and mortality. The commonest indication for

intubation of a pregnant patient is emergency caesarean delivery due to a

disturbing of falling foetal heart rate form. Other indications contain an

unsuccessful regional procedure preceding to a caesarean delivery, a high

blockade from a regional anaesthetic agent, systemic toxicity of local anaesthetic

agent, respiratory emergencies, and maternal cardiac asystole or arrest.

23

INCIDENCE-

Difficult intubation has been reported in 0.45 to 5.7 percentage of

intubations in pregnant women. Although a similar proportion of the general

surgical population (5.8 percentage) has difficult intubation13

, the concerns of

difficult intubation can be bigger in the pregnant population.

Failed intubation is much less common than difficult intubation, but it

occurs much more frequently in obstetric patients than in surgical patients.

Several observational studies of obstetric patients have reported failed intubation

rates of 0.26 to 0.4 percent. In contrast, in a retrospective study of 13,380

surgical patients, only 0.045 percent had failed intubation8.

STUDIES-

An identical case record study, a prospective observational study was

done in 2005-06 in 12 maternity clinics dealing with around 49 500 deliveries a

year14

.

Records were acquired from 1095 women who underwent general

anaesthesia for caesarean section, out of which 47% were classified as category I

and 18% classified as category IV. Tracheal intubation was scheduled in all the

cases with 97% undergoing rapid-sequence induction. Grading was done using

Cormack-lehane system and 3.6% had grade III and 0.6% had grade IV

laryngoscopic view. Almost 3.3% patients had a difficult intubation. Four failed

intubations among which laryngeal mask airway was used in 3 cases. In 94% of

24

cases posted electively and 64% of cases posted as an emergency. Eight cases

(1.2%) had regurgitation and one case c of aspiration (0.1%) was found out. No

cases had airway-related morbidity and mortality.

Samsoon GL et al7. conducted a study retrospectively in which patients

had previous history of failed intubation. In the same patient he found out that

there is a relationship between the degree of difficulty and the anatomy of the

oropharynx. Obstetric patients were studied initially but the study was also

extended to patients from various surgeries to increase the amount of cases

investigated. Over a 3-year period the incidence of failed intubation in obstetric

patients were 7of 1980 cases and 6 of 13,380 patients in surgical patients. So any

screening assessment which can add to our ability to foresee difficulty in

intubation must be received, as failure to intubate can in practice lead to fatality.

Kodali BS et al15

. piloted two studies to estimate airway changes during

labour. The Samsoon and Young modification of Mallampati airway class was

used in the first study. Photographs were taken at the onset and at the end of

labour. Class 4 airways were not included from initial participation. In the

second study, acoustic reflectometry was used to measure the upper airway

volumes at the onset and at the end of labour. Oral cavity volume, pharyngeal

cavity volume were calculated using acoustic reflectometry software15

.

Study I showed, the increase in airway class increased from before labour

to after labour with a significance (P<0.001). 33% patients had one grade

increase and 3 patients had 2 grades increase after labour.8 patients had class IV

25

at the end of labour and 30 patients had airway class III or class IV. Study 2,

significant decreases in oral cavity volume (P<0.05) and pharyngeal cavity

volume (P<0.05). No association was detected between airway changes during

labour and duration of sages of labour, or fluids administered during each stage

of labour in both studies. They concluded that airways can undergo change

during the process of labour. Hence, a careful airway assessment is important

just before giving anaesthesia during labour rather than gaining this information

from prelabour information.

EurRespir J et al16

. directed a study to determine whether there was upper

airway narrowing associated with pregnancy. 100 patients in the3rd trimester of

pregnancy were enrolled and 50 patients have agreed to be studied again 3

months post-delivery. 100 non pregnant patients were recruited. Acoustic

reflection was used to measure upper airway dimensions. Snoring was less

common in non-pregnant than pregnant women and pregnant women had

significantly smaller upper airway volumes than nonpregnant women at the

when seated, and smaller pharyngeal volumes in the seated, supine and lateral

position compared with the nonpregnant women. Pregnant females had lesser

pharyngeal volume compared with post labour in the seated, supine and lateral

position. In conclusion, this study confirmed increased changes and showed that

upper airways become narrower during the last trimester of pregnancy.

Another study by Izci B et al17

. Pregnant patients with pre-eclampsia

showed increased upper airway narrowing while sleeping. The study was done to

26

compare upper airway measurements in pregnant and nonpregnant women and

in pregnant women with pre-eclampsia. 50 women in the last trimester and 37

women suffering from pre-eclampsia were enrolled from the antenatal clinic and

compared with 50 nonpregnant women. Acoustic reflection was used to

measure dimensions of upper airway. Analysis was made using Student-

Newman-Keuls tests.

Snoring : 14% in non-pregnant women

: 28% in pregnant women

: 75% in pre-eclamptic women.

When in sitting, pregnant women had differences in upper airways than in

nonpregnant women, but no difference when in supine position. Study revealed

that women with pre-eclampsia have increased upper airway narrowing in both

sitting and supine position. These changes could add to the upper airway

narrowing episodes while sleeping in patients with pre-eclampsia, which can

further cause hypertension.

A study by Rocke DA et al18

. which emphasised on factors predicting

difficult airway in pregnancy showed that the capability to foresee these kind of

cases preoperatively would be of great importance. 1,500 patients undergoing

emergency and elective caesarean section under general anaesthesia underwent

preoperative airway assessment and risk factors for predicting difficult

27

intubation was recorded. Airway assessment was done using a modified

Mallampati score. Potential risk factors noted down were

1. Obesity as per BMI

2. Short neck using thyromental distance

3. Missing, protruding maxillary incisors

4. Receding mandible

5. Facial oedema and also swollen tongue.

Following induction of anaesthesia, the view seen during laryngoscopy

and difficulty in intubation were noted. Significant correlation between the view

of oropharyngeal structures and the view at laryngoscopy and difficulty in

intubation was present. Univariate analysis demonstrated a significant

association between difficult intubation and

1) Short Neck

2) Obesity

3) Missing Maxillary Incisors

4) Protruding Maxillary Incisors

5) Single Maxillary Incisor

6) Receding Mandible .

Both facial oedema (P = 0.414) and swollen tongue (P = 0.141) were not

found to be linked with difficult intubation. Multivariable analysis removed both

obesity and missing maxillary incisors as potential risk factors. Obesity was

eliminated from the study because of its very strong association with occurrence

28

of short neck. The probability of facing a difficult intubation from various

different combinations of mentioned above risk factors were determined18

.

A retrospective study by Djabatey EA et al19

. was performed of all

obstetric cases receiving general anaesthesia at hospital to find the incidence of

both difficult and failed intubation over a 8 year period. 3430 rapid sequence

general anaesthesia were given during this period and taken for study. 23

patients had difficult intubation. None of the patients had failed intubation.3

cases required awake fibreoptic intubation.

There are three keys for making a proper management of airway , which

are

1) Anticipation of difficulty by routine preoperative assessment,

2) Adequate preparation of the patient and also keeping the equipment

ready,

3) A very detailed plan of action should any complications arise.

The condition of both the foetus and the emergency of the interventional

procedure should be taken into account while dealing with obstetric patients. The

management of a difficult airway differs on whether it is predicted before or

after intubation. There is robust agreement among experts and doctors from all

over the world in airway management that definite strategies lead to better and

improved outcome. Patients in the obstetrics unit should have been assessed

airway preoperatively and also over different periods. On doing this we can be

prepared and preparation is very important to avoid catastrophe associated with

29

airway problems in obstetrics, particularly in those patients who are at risk for

caesarean delivery19

.

Evaluation of obstetrics should be done and they should include a record

of previous anaesthesia techniques used. The assessment allows the

establishment of wellbeing and rapport between the anaesthesiologist and patient

and this will be helpful when patients come for invasive procedures such as

awake intubation.

If any anatomical features that indicate there would be difficult intubation

via conventional means such as very large breasts, large tongue, difficulty in

neck flexion and massive jaw may also indicate difficult mask ventilation. If

there is any doubt about the ability to sustain airway patency then alternative

methods such as regional anaesthesia, local anaesthesia and awake intubation.

30

ASSESSMENT OF AIRWAY10

-

Identification and documentation of difficult airway before intervention is

gold standard of clinical management10

. The revolutionary article of Cass and

colleagues almost 50 years ago stresses this point. It is the first and primary step

in preparing for patient management and care. Selection of devices to aid the

airway, techniques to be done, and procedures to be done are all important on

airway evaluation. It is difficult to investigate difficult airway events all over the

world because these events occur very infrequently and a large group of

population must be studied. Numerous factors must be taken into account as

there are variety of factors that can influence airway anatomy and patients

entered into each study must be divided into several and various groups. Each

group must contain a very large number of patients. There are many other

additional problems such as expertise of the intubator. Different skill levels

among several operators present another variable into recognizing difficult and

failed intubations. In an ideal world, laryngoscopy should be performed by a

limited number of anaesthesiologists. Factors that must be organized include10

1) Type of laryngoscope as there are many different sizes,

2) The laryngoscope blade either macintosh, mc coys and millers,

3) The intubating position (sniffing position),

4) Degree of muscle relaxation,

5) The presence of a qualified trained assistant.

31

Other techniques apart from bedside evaluation to assess airway include

radiographs of the neck and other imaging techniques such as CT scans have

been supported to predict difficult intubation more accurately but these are too

costly. Newer techniques such as acoustic reflectometry are of very dubious

dependability. More specific and non-invasive measurements like bubble

inclinometer and goniometer can give us accurate measurements but these

methods have never made it to clinical practice.

SNIFFING POSITION10

-

The airway consists of 3 visual axes. They are long axis of the mouth,

axis of oropharynx and axis of larynx. In the normal neutral position of the head,

three axes form both acute and obtuse angles. To bring all these three axes into

proper alignment, McGill advised the “sniffing the morning air” position. The

true and proper sniffing position has two major components that are flexion of

cervical vertebrae and extension of atlanto-occipital joint. Cervical flexion helps

in approximating the laryngeal and pharyngeal axes. Atlanto-occipital extension

helps in bringing the oral axis into a proper and better alignment with the other

two laryngeal and pharyngeal axes. 35 degrees is the normal atlanto occipital

extension. Laryngeal opening becomes easy to visualise with optimal alignment

of these three airway axes. A reduction in gap between atlas and occiput along

with very prominent c1 spinous process can be difficult to perform

laryngoscopy. Inability to undertake the sniffing position is a very good

32

predictor of difficult intubation. Problems that can prevent the sniffing position

are

1) Cervical Vertebrae Arthritis

2) Ankylosing Spondylitis of Cervical Vertebrae

3) Cervical Vertebrae Fractures

4) Cervical Disc Protrusion

5) Atlantoaxial Subluxation

6) Cervical Vertebrae Fusion and

7) Application of Cervical Collar.

Obese patients have posterior neck pad of fat that hinder extension of

atlanto-occipital joint.

FIGURE 7 A) Normal position FIGURE 7 B) Sniffing position

33

MOUTH OPENING10

-

This is very important as it determines the amount of available space that

is present for manipulating laryngoscopes as well as endotracheal tubes20

. A

restricted mouth opening cannot accommodate both. Mouth opening depends on

the mobility of the temporomandibular joint (TMJ), which can function in 2

ways.

1) 1)Hinge like motion and

2) Gliding motion also known as translation.

The hinge like motion helps in pivoting the mandible over the maxilla.

Measuring the interincisor distance is a test to identify adequacy of mouth

opening. An interincisor distance of more than 3 cm offers adequate space for

intubation. This approximately correlates to two finger breadths. Factors which

interfere with mouth opening are

1) Masseter muscle spasm

2) TMJ dysfunction

FIGURE 8 – MEASURING INTER INCISOR GAP

34

DENTITION-

There is a high risk of damage to the teeth while instrumentation of

airway21

. There are several problems that can occur from any dental injury.

Teeth may be dislodged or broken. The main issue with broken teeth is that it

can migrate into the trachea and into the lung and cause obstruction of the lung

segment which can result in pneumonia. Any teeth that can be pulled easily with

fingers should be removed to be safe. During laryngoscopy, proper efforts

should be made to evade inserting pressure on maxillary incisors. In doing this,

laryngoscopes are placed into improper positions causing poor vision of glottis.

FIGURE 9- DENTITION

35

TONGUE-

Tongue occupies the space present in the mouth and also oropharynx.

The base of the tongue is in close proximity to the glottis. During laryngoscopy,

the base of tongue tends to fall posteriorly thus obstructing the view of the

glottis. The tongue should be displaced from its base anteriorly so that the glottis

structures can be visualised properly. The tongue is displaced with a

laryngoscope, to which Macintosh or Miller blades are attached. These

laryngoscopes help in pushing the tongue anteriorly. A large tongue fits very

poorly into mandibular space. Always a large tongue (macroglossia) is a very

good predictor of difficult intubation.

FIGURE 10- ANATOMY OF TONGUE

36

MALLAMPATI CLASSIFICATION23

-

Knowing the consequences of tongue size for effective laryngoscopy,

Mallampati SR22

predicted a system in 1985 to predict difficulty in

laryngoscopy. There is difficult laryngoscopy when not even the slightest part of

vocal cords are visualised. Mallampati along with Samsoon rationalised that a

bigger and larger tongue could be easily identified upon inspection of the mouth

opened. Both the classification systems analyse and relate the tongue size to that

of the oropharyngeal structures visualised. As discussed earlier a normal size

tongue can allow proper visualization of oropharyngeal structures. When the

tongue size increases, some oropharyngeal structures are unseen from view.

Therefore, both the investigators suggested systems that reasoned for this

premise.

Application of both Mallampati and Samsoon classification system is

very easy and is painless to the patient as it is non-invasive. “The patient is

seated in the neutral position. The mouth is opened as wide as possible and the

tongue is protruded as far as possible. Phonation is discouraged because it raises

the soft palate and allows visualization of additional structures. The observer

looks for specified anatomic landmarks. They are the fauces, pillars, uvula, and

soft palate”. The Mallampati classification system employs 3 groups and the

Samsoon classification system utilises 4 groups.

37

FIGURE-11 MALLAMPATI CLASSIFICATION

“ORIGINAL MALLAMPATI TEST23

–

Grade 1 : Faucial pillars, soft palate, and uvula could be visualized

Grade 2 : Faucial pillars and soft palate could be visualized, but

uvula was masked by base of the tongue.

Grade 3 : Only soft palate could be visualized”

“MODIFIED MALLAMPATI TEST 24–

Class 1- : Soft palate, fauces, uvula, pillars seen

Class 2 : Soft palate, fauces, uvula seen

Class 3 : Soft palate, base of uvula seen

Class 4 : Soft palate not visible at all

Class 0 : Ability to see any part of the epiglottis on mouth”

38

A retrospective study was conducted by Samsoon and Young24

and they

concluded that the Mallampati test can be used to monitor the population to

detect those patients who are at more risk for difficult airway. Patients with class

III and IV are at risk of difficult airway. Classes I and II were not associated

with any serious problems. “Since we began the study, we have been so

impressed by the positive correlation between the classification and the ease. or

otherwise, of intubation, that in our obstetric department we most vigorously

encourage early use of regional analgesia in those classified as grades III and

IV, in the hope that general anaesthesia may be avoided”.

A meta-analysis was conducted by Shiga T et al8. of various bed side

screening tests to properly predict difficult intubation, Thirty-five studies

(50,760 patients) were selected. The overall incidence of difficult intubation was

5.8%. Screening tests included the

1. Mallampati classification,

2. Sternomental distance,

3. Thyromental distance. Each and every test yielded very poor to moderate

sensitivity (20-62%) and moderate to fair specificity (82-97%).

A combination of both Mallampati classification and thyromental

distance was found to be more useful in identifying patients for difficult airway.

When used alone the screening tests that are being used carries poor

discriminative power for prediction of difficult airway. This is the limitation of

bedside tests to be used as methods for predicting difficult airway.

39

A meta-analysis was conducted by Lee etal25

. comparing both Mallampati

and modified Mallampati classification and established their specificity and

sensitivity. The Mallampati test was used properly to correctly predict the

incidence of difficult tracheal intubation in 5 studies registering12,351 patients.

The popularity of difficult intubation ranged from 5% to 13%. In the study it

was found that Mallampati classification had low sensitivities (0.35 to 0.67) and

differing specificities (0.64 to 1.04).

40

The other tests for assessing airway bed side are –

THYROMENTAL DISTANCE–

The patient is asked to extend his head atatlanto-occipital joint26

. The

structures to be identified are mentum of mandible and thyroid cartilage in

front of the neck. “Adam's apple” (thyroid notch) serves as a very good

landmark for the thyroid cartilage as it is very superficial it can be easily

identified. The distance between the two landmarks the thyroid cartilage and

mentum is measured in three ways.

1. A set of spacers can be used

2. A pocket ruler can be used

3. Observer's or even patient‟s own fingers can be used.

The normal distance between mentum and thyroid cartilage is 6.5 cm. A

distance greater than 6 cm is indicative of easy intubation. A distance of 6 cm

or less is predictive of difficult intubation.

FIGURE 12- THE ARROWED LINE SHOWING THE MENTUM AND

THE THYROID CARTILAGE IS THE THYROMENTAL DISTANCE.

41

UPPER LIP BITE TEST27

-

The modified temporomandibular test is the upper lip bite test. The

upper lip bite test is implemented by requesting the patient to move the

incisors as high as possible on the upper lip. The exercise is like to biting the

lip. If the teeth gets above or touches the vermilion border then it is easy to

predict that there is adequate space for laryngoscopy. If the teeth cannot touch

the vermilion border then it is considered as difficult intubation as there is not

much space for laryngoscopy.

FIGURE 13- A & B SHOW THAT THE VERMILION BORDER CAN BE

TOUCHED AND IT IS A PREDICTOR FOR EASY LARYNGOSCOPY.

C&D SHOW THAT THE VERMILION BORDER CANNOT BE

TOUCHED AND THAT THERE WILL NOT BE ENOUGH SPACE FOR

LARYNGOSCOPY.

METHODOLOGY

42

METHODOLOGY

This study commenced after obtaining clearance from Institutional

Human Ethics committee (IHEC) for a study period of 10 months starting from

August 2015.

Pregnant women at 32-34 weeks of gestation coming to the Outpatient

department for antenatal check-up were approached and included in this study

after explaining them about the study thoroughly and obtaining informed and

written consent.

INCLUSION CRITERIA:

1. Above 21 years

2. Indian population

EXCLUSION CRITERIA:

1. Below 21 years

2. Non-Indian population.

3. Patients who deny consent.

4. Patients with eclampsia.

43

The investigators involved in this were

1) Principal investigator : Also the observer 1 and the postgraduate involved

in this study who was responsible for explaining and obtaining written

consent, evaluation of measurements over the time periods, compilation

of study data and statistical analysis of the study.

2) Co-investigator: Guide of the study involved in studying previous

literature and also statistical analysis of the study.

STUDY DESIGN:

Observational prospective study.

SAMPLE SIZE CALCULATION:

Formula used to calculate is:

n=(z∝^2 PQ)/L^2

Where n is sample size, zα= 95% confidence interval

1.96 standard deviation

P= Population prevalence during previous studies= 37%.

Q= [100-P].

L= Allowable error (20%).

n=(〖1.96〗^2 x37x[100-37])/〖[20/100 x37]〗^2

n = 164.

Sample size of my study is 164.

44

MEASUREMENTS:

The following measurements were taken

1) Height – was measured in centimetres (cms) with the subject standing

on a flat surface with the head, shoulders and heels touching the wall.

2) Weight – was measured in kilograms (kgs) with the subject standing

on a analogue weighing machine without any support.

3) BMI was calculated in using quartet‟s index.

4) Weight gain during pregnancy was recorded from the history.

STUDY :

Each patient‟s contact information was obtained for follow up at various

time intervals. The study consists of primary investigator observing the

Mallampati classification in the subjects at four time intervals over the course of

pregnancy and labour.

TIME INTERVALS :

1st Time interval: Between 32-34 weeks of gestation where patients are

recruited from the Outpatient department.

2nd

Time interval: At the time of admission for safe confinement usually

at 40 weeks of gestation.

3rd

Time interval: 2-4 hours after delivery of the baby.

4th

Time interval: 48-72 hours after delivery.

45

DATA OBTAINED:

1) Amount of intravenous fluids administered during each single stage

of labour.

2) Duration of each single stage of labour.

Mallampati scores recorded at each time interval were stored and studied.

The change in the scores were studied and were compared to factors such as

duration of labour, BMI, Weight gain during pregnancy and amount of

intravenous fluids administered during labour.

RESULTS

46

RESULTS

All statistical analysis were done using SPSS version 20.0 Mean,

standard deviation and P value were computed for all data. Wilcoxon signed

rank test was performed to find the association between multiple variables.

Wilcoxon signed rank test30

:

Was preferred over paired T-test because the multiple variables were not

distributed equally. It is an analysis or a hypothetical statistical analysis

which is non-parametric which can be used in conditions such as when two

related samples or a single sample with repeated measurements that can help

us in assessing whether the mean ranks of the population can differ. It is also

a paired difference test. It can be used when the population cannot be

predicted or assumed properly and also as an substitute to the paired

Student's t-test.Assumptions are:

1. Data come from the same group of population and are paired.

2. Pair is selected independently and randomised.

3. An ordinal scale is used to measure the data obtained.

47

TABLE 1: DISTRIBUTION OF STUDY POPULATION IN DIFFERENT

AGE GROUPS

Frequency

in the study

Percentage Valid

Percentage

Cumulative

Percentage

<30yrs 146 89.0 89.0 89.0

>30yrs 18 11.0 11.0 100.0

Total no. 164 100.0 100.0

FIGURE 1: DISTRIBUTION OF STUDY POPULATION IN DIFFERENT

AGE GROUPS

A total of 164 pregnant women were included in the study and about 89%

of them were below 30 years of age and remaining 11% were between 30-35

years of age.

48

TABLE 2 – CO MORBIDITIES AMONG STUDY POPULATION

Frequenc

y

Percent Valid

Percent

Cumulative

Percent

Nil 84 51.2 51.2 51.2

HYPERTENSIO 28 17.1 17.1 68.3

DIABETES MILLETUS 16 9.8 9.8 78.0

HYPOTHYROID 21 12.8 12.8 90.9

ANEMIA 15 9.1 9.1 100.0

TOTAL 164 100.0 100.0

FIGUTRE 2 – CO MORBIDITIES AMONG STUDY POPULATION

49

TABLE 3 – WEIGHT GAIN AMONG STUDY POPULATION

Frequency Percent Valid Percent Cumulative

Percent

<15 121 73.8 73.8 73.8

>15 43 26.2 26.2 100.0

Total 164 100.0 100.0

FIGURE 3 – WEIGHT GAIN AMONG STUDY POPULATION

50

TABLE 4- DURATION OF FIRST STAGE OF LABOUR

Frequency Percent Valid Percent

Cumulative

Percent

<15hrs 21 12.8 12.8 12.8

15-20hrs 111 67.7 67.7 80.5

>20hrs 32 19.5 19.5 100.0

Total 164 100.0 100.0

FIGURE 4- DURATION OF FIRST STAGE OF LABOUR

51

TABLE 5- DURATION OF SECOND STAGE OF LABOUR

Frequency Percent Valid Percent Cumulative

Percent

Valid

<1hr 81 49.4 49.4 49.4

>1hr 83 50.6 50.6 100.0

Total 164 100.0 100.0

FIGURE 5- DURATION OF SECOND STAGE OF LABOUR

52

TABLE 6- DISTRIBUTION OF INTRAVENOUS FLUIDS IN FIRST

STAGE OF LABOUR

Frequency Percent Valid Percent Cumulative

Percent

<500ml 6 3.7 3.7 3.7

500-1000ml 138 84.1 84.1 87.8

>1000ml 20 12.2 12.2 100.0

Total 164 100.0 100.0

FIGURE 6- DISTRIBUTION OF INTRAVENOUS FLUIDS IN FIRST

STAGE OF LABOUR

53

TABLE 7 – DISTRIBUTION OF SECOND STAGE OF LBOR IN

SECOND STAGE OF LABOUR

Frequency Percent Valid Percent Cumulative

Percent

<50ml 1 .6 .6 .6

50-100ml 67 40.9 40.9 41.5

>100ml 96 58.5 58.5 100.0

Total 164 100.0 100.0

FIGURE 7 – DISTRIBUTION OF SECOND STAGE OF LBOR IN

SECOND STAGE OF LABOUR

54

TABLE 8 – BMI DISTRIBUTION AMONG SUBJECTS

Frequency Percent Valid Percent Cumulative

Percent

18.5-24.9 9 5.5 5.5 5.5

25.0-29.99 104 63.4 63.4 68.9

30.0-34.99 50 30.5 30.5 99.4

35.0-39.99 1 .6 .6 100.0

Total 164 100.0 100.0

FIGURE 8 – BMI DISTRIBUTION AMONG SUBJECTS

55

TABLE 9 – DISTRIBUTION OF GRAVIDA AMONG SUBJECTS

Frequency Percent Valid Percent Cumulative

Percent

0 1 .6 .6 .6

1 99 60.4 60.4 61.0

2 39 23.8 23.8 84.8

3 17 10.4 10.4 95.1

4 6 3.7 3.7 98.8

5 1 .6 .6 99.4

6 1 .6 .6 100.0

Total 164 100.0 100.0

FIGURE 9 – DISTRIBUTION OF GRAVIDA AMONG SUBJECTS

56

TABLE 10- DISTRIBUTION OF MALLAMPPATI CLASS 1 AMONG

TIME INTERVALS

MP I

Frequency Percent Valid Percent Cumulative

Percent

1 3 1.8 1.8 1.8

2 95 57.9 57.9 59.8

3 61 37.2 37.2 97.0

4 5 3.0 3.0 100.0

Total 164 100.0 100.0

FIGURE 10- DISTRIBUTION OF MALLAMPPATI CLASS 1 AMONG

TIME INTERVALS

57

TABLE 11- DISTRIBUTION OF MALLAMPPATI CLASS II AMONG

TIME INTERVALS

MP II

Frequency Percent Valid Percent Cumulative

Percent

1 1 .6 .6 .6

2 32 19.5 19.5 20.1

3 77 47.0 47.0 67.1

4 54 32.9 32.9 100.0

Total 164 100.0 100.0

FIGURE 11 - DISTRIBUTION OF MALLAMPPATI CLASS II AMONG

TIME INTERVALS

58

TABLE 12- DISTRIBUTION OF MALLAMPPATI CLASS III AMONG

TIME INTERVALS

MP III

Frequency Percent Valid Percent Cumulative Percent

1 1 .6 .6 .6

2 35 21.3 21.3 22.0

3 79 48.2 48.2 70.1

4 49 29.9 29.9 100.0

Total 164 100.0 100.0

FIGURE 12- DISTRIBUTION OF MALLAMPPATI CLASS III AMONG

TIME INTERVALS

59

TABLE 13- DISTRIBUTION OF MALLAMPPATI CLASS IV

AMONG TIME INTERVALS

MP IV

Frequency Percent Valid Percent Cumulative

Percent

1 2 1.2 1.2 1.2

2 50 30.5 30.5 31.7

3 92 56.1 56.1 87.8

4 20 12.2 12.2 100.0

Total 164 100.0 100.0

FIGURE 13- DISTRIBUTION OF MALLAMPPATI CLASS IV AMONG

TIME INTERVALS

60

DESCRIPTIVE STATISTICS

N Mean Std. Deviation

MP I 164 2.41 .585

MP II 164 3.12 .733

MP III 164 3.07 .731

MP IV 164 2.79 .660

This table shows the mean values of all Mallampati classes, MP I is on an

average 2.41, MP II on an average is 3.12, MP III on an average is 3.07 and MP

IV on an average is 2.79.

61

WILCOXON SIGNED RANKS TEST

Test Statisticsc

MP II -

MP I

MP III -

MP I

MP IV -

MP I

MP III -

MP II

MP IV -

MP III

MP IV

- MP II

Z -9.641a -9.312

a -7.750

a -2.000

b -6.374

b -7.086

b

Asymp. Sig.

(2-tailed) .000 .000 .000 .046 .000 .000

Based on the above non-parametric test , P <0.001 is significant.

Assosciation is found out between different classes using p value.

There is significant difference between MPI-II (z-9.641, P=<0.001)

There is no significant difference between MP II-III (z -2.000, P=<0.001)

, so this signifies that the Mallampati which was recorded at second time interval

and third interval does not differ much , Mallampati at safe confinement and

Mallampati at 2-4 hours after labour.

62

COMPARISION OF MALLAMPATI CLASS AT II AND IV TIME

INTERVALS WITH THE DURATION OF FIRST STAGE OF LABOUR

Ranks

N Mean Rank Sum of

Ranks

MP II – first stage

duration

Negative Ranks 3a 39.50 118.50

Positive Ranks 123b 64.09 7882.50

Ties 38c

Total 164

MP IV – first stage

duration

Negative Ranks 9d 39.50 355.50

Positive Ranks 98e 55.33 5422.50

Ties 57f

Total 164

a. MP II < first stage duration

b. MP II > first stage duration

c. MP II = first stage duration

d. MP IV < first stage duration

e. MP IV > first stage duration

f. MP IV = first stage duration

63

Test Statisticsb

MP II – first stage

duration

MP IV – first stage

duration

Z -9.793a -8.300

a

Asymp. Sig. (2-tailed) .000 .000

a. Based on negative ranks.

b. Wilcoxon Signed Ranks Test

This shows the significance of change in Malllampati class from 2nd

time

interval to the 4th

time interval with respect to duration of first stage of

LABOUR as both the P values are 0.000.

64

COMPARISION OF MALLAMPATI CLASS AT II AND IV TIME

INTERVALS WITH DURATION OF SECOND STAGE OF LABOUR

AND AMOUNT OF INTRAVENOUS FLUIDS ADMINESTERED

DURING SECOND STAGE OF LABOUR.

Descriptive Statistics

N Mean Std. Deviation Minimum Maximum

Second stage duration 164 1.51 .501 1 2

Second stage iv 164 2.58 .507 1 3

MP II 164 3.12 .733 1 4

MP IV 164 2.79 .660 1 4

Wilcoxon Signed Ranks Test

Ranks

N Mean Rank Sum of Ranks

MP II – second stage

duration

Negative Ranks 0a .00 .00

Positive Ranks 150b 75.50 11325.00

Ties 14c

Total 164

MP IV – second stage

iv

Negative Ranks 23d 34.61 796.00

Positive Ranks 51e 38.80 1979.00

Ties 90f

Total 164

65

a. MP II < second stage duration

b. MP II > second stage duration

c. MP II = second stage duration

d. MP IV < second stage iv

e. MP IV > second stage iv

f. MP IV = second stage iv

Test Statisticsb

MP II – second stage

duration

MP IV – second

stage iv

Z -10.847a -3.490

a

Asymp. Sig. (2-tailed) .000 .000

Exact Sig. (2-tailed) .000 .000

Exact Sig. (1-tailed) .000 .000

Point Probability .000 .000

a. Based on negative ranks.

b. Wilcoxon Signed Ranks Test

This shows the significance of Mallampati class at 2nd

time interval and

amount of intravenous fluids administered during second stage of LABOUR.

66

COMPARISION OF MALLAMPATI CLASS AT III AND IV TIME

INTERVALS WITH RESPECT TO AMOUNT OF INTRAVENOUS

FLUIDS ADMINESTERED DURING FIRST STAGE OF LABOUR

Ranks

N Mean Rank Sum of Ranks

MP III – first stage

iv

Negative Ranks 1a 45.00 45.00

Positive Ranks 125b 63.65 7956.00

Ties 38c

Total 164

MP IV – first stage

iv

Negative Ranks 4d 45.50 182.00

Positive Ranks 103e 54.33 5596.00

Ties 57f

Total 164

a. MP III < first stage iv

b. MP III > first stage iv

c. MP III = first stage iv

d. MP IV < first stage iv

e. MP IV > first stage iv

f. MP IV = first stage iv

67

Test Statisticsb

MP III – first stage iv MP IV – first stage iv

Z -10.111a -9.113

a

Asymp. Sig. (2-tailed) .000 .000

a. Based on negative ranks.

b. Wilcoxon Signed Ranks Test

This shows that there is significance P values 0.000 of change in

Mallampati class at III and IV time intervals with respect to amount of

intravenous fluids administered during first stage of LABOUR.

68

COMPARISION OF MALLAMPATI CLASS AT III AND IV TIME

INTERVALS WITH RESPECT TO AMOUNT OF FLUIDS

ADMINISTERED DURING SECOND STAGE OF LABOUR

Ranks

N Mean Rank Sum of Ranks

MP III – second

stage iv

Negative Ranks 12a 34.00 408.00

Positive Ranks 74b 45.04 3333.00

Ties 78c

Total 164

MP IV – second

stage iv

Negative Ranks 23d 34.61 796.00

Positive Ranks 51e 38.80 1979.00

Ties 90f

Total 164

a. MP III < second stage iv

b. MP III > second stage iv

c. MP III = second stage iv

d. MP IV < second stage iv

e. MP IV > second stage iv

f. MP IV = second stage iv

69

Test Statistics

MP III – second

stage iv

MP IV – second stage

iv

Z -6.709 -3.490

Asymp. Sig. (2-tailed) .000 .000

a. Based on negative ranks.

This shows that there is significance P values 0.000 with increase in

Mallampati class at III and IV time intervals with respect to amount of

intravenous fluids administered during second stage of LABOUR.

70

COMPARISION OF MALLAMPATI CLASS AT I AND II TIME

INTERVALS WITH RELATION TO WEIGHT GAIN DURING

PREGNANCY

Ranks

N Mean Rank Sum of Ranks

MP I – Weight

gain

Negative Ranks 0a .00 .00

Positive Ranks 147b 74.00 10878.00

Ties 17c

Total 164

MP II – Weight

gain

Negative Ranks 0d .00 .00

Positive Ranks 163e 82.00 13366.00

Ties 1f

Total 164

a. MP I <Wt gain

b. MP I >Wt gain

c. MP I = Wt gain

d. MP II <Wt gain

e. MP II >Wt gain

f. MP II = Wtgainnew

71

Test Statisticsb

MP I - Wtgainnew MP II - Wtgainnew

Z -11.073a -11.473

a

Asymp. Sig. (2-tailed) .000 .000

a. Based on negative ranks.

b. Wilcoxon Signed Ranks Test

This shows that there is significance P values 0.000 in increasing

Mallampati class at 1st and 2

nd time intervals.

72

COMPARISION OF MALLAMPATI CLASS AT I AND II TIME

INTERVALS WITH RESPECT TO GRAVIDA OF THE PATIENT

Ranks

N Mean Rank Sum of Ranks

MP I –

Gravida

Negative Ranks 20a 53.43 1068.50

Positive Ranks 108b 66.55 7187.50

Ties 36c

Total 164

MP II –

Gravida

Negative Ranks 10d 44.75 447.50

Positive Ranks 138e 76.66 10578.50

Ties 16f

Total 164

a. MP I <Gravida

b. MP I >Gravida

c. MP I = Gravida

d. MP II <Gravida

e. MP II >Gravida

f. MP II = Gravida

73

Test Statisticsb

MP I - Gravida MP II - Gravida

Z -7.535a -9.848

a

Asymp. Sig. (2-tailed) .000 .000

a. Based on negative ranks.

b. Wilcoxon Signed Ranks Test

This shoes that there is significance P values 0.000 between increasing

Mallampati class and gravida scores of the patient.

74

COMPARISION OF MALLAMPATI CLASS AT I AND II TIME

INTERVALS IN RESPECT TO BODY MASS INDEX OF THE

PATIENTS

Ranks

N Mean Rank Sum of Ranks

MP I – BMI

Negative Ranks 119a 60.59 7210.00

Positive Ranks 1b 50.00 50.00

Ties 44c

Total 164

MP II – BMI

Negative Ranks 42d 31.74 1333.00

Positive Ranks 20e 31.00 620.00

Ties 102f

Total 164

a. MP I < BMI

b. MP I > BMI

c. MP I = BMI

d. MP II < BMI

e. MP II > BMI

f. MP II = BMI

75

Test Statisticsb

MP I - BMI MP II – BMI

Z -10.110a -2.853

a

Asymp. Sig. (2-tailed) .000 .004

a. Based on positive ranks.

b. Wilcoxon Signed Ranks Test

This shows that there is significance P values 0.000 between increasing

Mallampati class at I and II time intervals in relation to BMI.

DISCUSSION

76

DISCUSSION

Safe conduct of anaesthesia and maintenance of is an important goal for

an anaesthesiologist. Obvious airway abnormalities initiate a chain of

communications that help in getting valuable assistance; however unrecognized

difficult airway may lead to serious consequences. Several clinical tests over

many years have been suggested for recognizing patients who may have difficult

airway preoperatively but unfortunately there is still no specific test that can

accurately predict a difficult airway. As discussed before difficult intubation

remains the most important and prevalent condition to cause anaesthesia related

morbidity and mortality in obstetric population. So it remains of top priority for

an anaesthesiologist to tackle this problem.

There have been many studies which has discussed about airway

changes in pregnancy and many of the studies have shown that airway changes

in pregnancy are very much prevalent and found that airway gets more difficult

as the pregnancy progresses. But only a few studies have been conducted to

predict the factors causing these changes in airway in pregnancy. So our study

was aimed to study as to predict the factors causing these changes. Predicting

these factors can help an anaesthesiologist in anticipating difficult intubation

beforehand and be prepared for the challenge.

Previous studies conducted were from western countries and a study of

this kind has not been conducted in Indian population. According to Indian

literature airway changes during pregnancy was not a major factor in obstetrics

77

because it was believed that airway changes does not occur much in pregnancy

due to high incidence of malnutrition and less weight gain during pregnancy. But

nowadays as obesity is becoming more prevalent and improvement of nutritional

status among Indian women because of education and awareness has shown

more incidence of pregnancy related disorders becoming a major concern. This

increased prevalence in obesity and weight gain in recent times have led

increased changes in airway over the course of pregnancy , so Indian population

also are more prone for difficult intubation airway related morbidity and

mortality in obstetrics. No studies have been conducted to suggest this in Indian

population. Our Study shows that almost in 64% of pregnant women airway has

changed from either Mallampati 1or 2 to Mallampati 3or 4 in Indian population.

This shows the changing trend in Indian population.

The even more important part is to find or predict the factors causing

these changes . No study of such has been done in Indian population. Our study

aims at predicting the factors causing these changes in airway in Indian

population.

Our study has been done at PSG institute of Medical sciences and

research, Coimbatore, Tamil nadu, India by recruiting patients coming to the

outpatient department of obstetrics. Study was done as discussed in the

methodology.

In a study conducted by Pilkington and colleagues28

where they examined

the Mallampati class in pregnant women at two different time intervals. The time

78

intervals were at 12 weeks of gestation and 38 weeks of gestation. They found

out that there was significant increase in Mallampati class at 38 weeks of

gestation. There was34% increase of class IV at 38 weeks of gestation. They

emphasized a relationship between airway change and body weight gain during

pregnancy. “We observed a increase in patient‟s Mallampati class that was

significant (P< 0.001) and we also found that increase in body weight was

predictive for airway changes”. The average body weight gain in their study was

11 kg but it was 14.3 kg in our study. Consequently, it is possible that there is

increase in Mallampati class connected to increased gain in body weight can

occur before 33 weeks of gestational period.

Studies comparing BMI and increase in Mallampati during pregnanacy

are not found. In our study we compared BMI of the patients with changing

Mallampati scores in pregnancy and found out that average BMI was 26.5 and

there was a significant (P>0.001) association between increase in BMI and

increase in Mallampati during pregnancy.

In a study, Kodali and colleagues15

reported that there was significant

change in Mallampati class during pregnancy and labour and also found that

there is 1.7 times elevation in the Mallampati classes III and IV in the post-

partum in compared to pre-labour evaluation. From the findings we have

analysed in our study there were similar results accounting for almost 64%

increase in Mallampati scores evaluated pre and post labour. Agreeable with the

findings of Kodali and colleagues' findings, we succeeded in identifying the

79

factors that can be predicted to cause increase in Mallampati class. This can be

attributed to the airway oedema that can be caused by fluid accumulation and

increased straining or Valsalva efforts. We concluded that two important factors

such as volume of fluids administered intravenously during first stage of labour

and durations of both first stage of labour and second stage of labour might be

very potential factors that can cause airway changes in pregnant women.

So in our study we have decided to measure and the amount of

intravenous fluids being administered during first and second stage of labour.

We have found out that the amount of fluid being administered during first stage

of labour that there was significant ( P<0.001) increase in Mallampati from class

1or 2 to 3or 4 .

It is hypothesized that prolonged valsalva efforts during labour causing

fluid accumulation of fluid causing oedema of upper airway leading to difficult

airway in pregnant women. So we have decided to calculate the duration of the

first stage and second stage of labour. In our study we have found out that the

average first stage of labour duration was 16.2 hours and there was significant

(P<0.001) change in Mallampati scores. The average second stage of labour

duration was around 45 minutes and found out that there was no significant

(P>0.001) association with changes in the Mallampati scores. This may be

attributed to the fact that majority of the valsalva are done in first stage of labour

to help in delivery of foetus, whereas in second stage of labour the number of

valsalva done are reduced as the foetus is delivered.

80

Finally, we even evaluated whether or not the Mallampati class changes

that were present immediately after labour reversed after 48-72 hours after

delivery of foetus and also whether or not we can predict the second stage of

labour duration and the amount of intravenous fluids given during labour can be

predictive. Our results showed significant trend that there is increase of

Mallampati class in pregnant women who had Mallampati class III or IV

throughout labour, but these changes did not get fully reversed even after 48

hours post-labour in patients who had reached Mallampati class IV. We suggest

that according to our study we could identify factors such as amount of

intravenous fluids administered during first stage of labour and duration of first

stage of labour were the predictive factors that anticipated the presence of

increase in Mallampati class at 48 hours after delivery of the foetus.

In a study conducted by M.BOUTTONETT 29

published in the British

Journal of Anaesthesia in 2005 they have found that majority of the pregnant

women have undergone airway changes but they were not able to predict the

factors associated with airway changes as the couldn‟t find any significant

changes with amount of intravenous fluids administered and duration of labour.

In our study we have found that there is significant association between airway

changes and factors such as weight gain , BMI, fluids administered during first

stage of labour and also duration of first stage of labour.

CONCLUSION

81

CONCLUSION

This is a observational prospective study which consists of 164 subjects

who were examined over their period of pregnancy and labour at four different

time intervals. The Mallampati class was studied over these periods and also the

predicting factors such as weight gain during pregnancy, body mass index,

duration of first and second stage of labour and amount of intravenous fluids

administered during first and second stage of labour were noted.

Statistical analysis was done by Wilson‟s signed rank test which is a

nonparametric test used as there are many variables to be studied.

We conclude that in our study the change in Mallampati class of the first

interval i.e.; at 32-34 weeks compared to change in Mallampati class at third

interval i.e.; at 4-6 hours after delivery of the baby is present in 64% of the study

population.

On evaluating the different factors causing these changes we have found

that there is a strong association between the BMI of the patient and the change

in Mallampati score as patients over BMI of 25 were significant ( P <0.001) with

respect to Mallampati score. We conclude that BMI over 25 is a predictive factor

of increasing Mallampati class during the course of pregnancy and labour.

We found that weight gain over 15 kilograms during pregnancy has

significant ( P< 0.001) association with increasing trend of Mallampati class

over course of pregnancy an labour.

82

We also found that duration of first stage of labour carries a higher

significance (P <0.001) in increasing the Mallampati score which is attributed to

increased number of valsalva manoeuvres causing airway oedema. However the

duration of second stage of labour did not have a significance (P > 0.001) with

increasing in Mallampati score which may be due to less straining and decreased

duration.

Intravenous fluids given during the first stage of labour also had a

significance (P <0.001) in increasing Mallampati class during the course of

labour.

We conclude our study by postulating that there is definitive increase of

Mallampati class during the course of pregnancy and labour and factors that can

used to predict these changes are weight gain during pregnancy, Body mass

index (BMI), duration of first stage of labour and intravenous fluids

administered during first stage of labour.

Any pregnant woman coming for anaesthesia should be properly

examined and all the mentioned factors should be noted and taken into

consideration by an anaesthesiologist and be prepared for a difficult airway

situation.

BIBLIOGRAPHY

BIBLIOGRAPHY

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Retrieved 24 March 2011.

ANNEXURES

ANNEXURES

CONFIDENTIALITY FORM

From,

Dr.JAYAPRAKASH ARUNACHALAM,

POST GRADUATE,

DEPARTMENT OF ANAESTHESIOLOGY,

PSGIMS&R,

COIMBATORE.

TO WHOMSOEVER IT MAY CONCERN

I, Dr.JAYAPRAKASH ARUNACHALAM, am undertaking a study titled

‟ PREDICTING THE AIRWAY CHANGES DURING THE COURSE OF

PREGNANCY, LABOUR AND AFT ER DELIVERY USING

MALLAMPATI CLASSIFICATION AMONG INDIAN WOMEN.‟

I hereby assure that the data taken will be used only for the approved

study and the subject information and subject identity will not be revealed to

anybody under any circumstances.

Thanking you,

Yours sincerely,

Signature of PI Signature of Co-investigator/s:

Date:

Application form for requesting Waiver of Written Informed Consent/

waiver of consent

(To be filled by PI)

1. Proposal Number :

2. Principal Investigator‟s name:

3. Department:

4. Title of project:

5. Names of co-investigators:

6. Request for waiver of informed consent:

Please check the reason(s) for requesting waiver

1. Research involves „not more than minimal risk‟

2. There is no direct contact between the researcher and participant

3. Emergency situations

4. Any other (please specify)

I hereby assure that the rights of the participants will not be violated.

Undertaking: I hereby declare that contents of the soft and hard copies of this

document submitted to the IHEC are the same.

Principal Investigator‟s signature with date:

CONSENT FORMS IN TAMIL

DATA COLLECTION PROFORMA

NAME :

AGE :

OCCUPATION :

ADDRESS AND CONTACT INFO :

OBSTETRIC SCORE :

HEIGHT :

WEIGHT :

BMI :

LMP AND EDD :

GAIN IN BODY WEIGHT DURING PREGNANCY:

CO-MORBID ILLNESS :

MALLAMPATI AT 1ST

TIME INTERVAL:

MALLAMPATI AT 2ND

TIME INTERVAL:

MALLAMPATI AT 3RD

TIME INTERVAL:

MALLAMPATI AT 4TH

TIME INTERVAL:

DURATION OF 1ST

STAGE OF LABOUR:

DURATION OF 2ND

STAGE OF LABOUR:

AMOUNT OF INTRAVENOUS FLUIDS GIVEN IN 1ST

STAGE OF

LABOUR :

AMOUNT OF INTRAVENOUS FLUIDS GIVEN IN 2ND

STAGE OF

LABOUR :

MASTER CHART

MASTER CHART

S No. Age Weight Height BMI Wt gain Gravida Para Live Abortion MP I MP II MP III MP IV 1st stage 2nd stage IV 1st IV 2nd Co morbs

1 29 85 170 29.4 18 2 1 0 1 3 4 4 3 20 2 620 130

2 26 62 150 27.6 11 1 0 0 0 3 3 3 3 21 2 500 180

3 29 64 153 27.3 17 2 1 0 1 2 3 3 2 18 1 380 100 1

4 31 70 162 26.7 13 1 0 0 0 2 2 2 2 21 1.45 800 190

5 29 72 158 28.8 16 3 1 1 2 2 4 4 3 15 1 620 280 3

6 22 80 165 29.4 13 1 0 0 0 2 3 3 2 18 1.3 500 250

7 28 72 152 31.2 17 1 0 0 0 2 4 4 3 20 2 760 400

8 24 66 151 28.9 12 2 0 0 1 2 3 3 3 21 2 780 120

9 26 78 163 29.4 15 1 0 0 0 1 3 3 2 23 2.3 1000 250 4

10 22 68 160 26.6 12 1 0 0 0 2 3 3 1 20 1.3 750 180

11 26 68 160 26.6 15 1 0 0 0 2 3 3 2 22 1.45 650 170

12 28 63 149 28.4 12 1 0 0 0 2 2 2 2 19 2 800 125

13 23 78 168 27.6 11 2 1 1 0 2 2 2 2 16 1 700 300

14 25 73 162 27.8 16 1 0 0 0 2 4 4 3 21 2.3 720 200 3

15 25 60 153 25.6 15 2 0 0 1 2 4 4 3 18 1 500 100

16 25 68 158 27.2 11 4 1 1 2 2 3 3 3 14 1 450 75

17 29 72 152 31.2 13 2 1 1 0 2 3 3 2 15 1 600 125 2

18 27 68 162 25.9 14 1 0 0 0 2 3 3 3 19 2 800 150

19 27 76 164 28.3 13 2 0 0 1 3 3 3 3 16 1.3 550 200 1

20 25 77 159 30.5 16 1 0 0 0 3 4 4 4 18 1 600 150 1

21 22 65 154 27.4 16 1 0 0 0 2 4 4 3 22 2 780 120 2

22 23 79 165 29 17 2 1 1 0 2 4 3 3 21 1 650 120 1

23 25 78 165 28.7 15 1 0 0 0 3 3 3 3 20 2 800 130 4

24 23 67 159 26.5 16 1 0 0 0 3 4 3 3 18 1.3 650 110

25 32 68 165 25 13 2 1 0 1 2 4 3 3 16 1.2 750 130 2

26 22 75 163 28.2 16 1 0 0 0 2 3 3 3 19 2 860 140

27 22 65 163 24.5 12 1 0 0 0 2 2 2 2 17 1.2 600 100

28 25 78 163 29.4 16 2 0 0 1 3 4 3 3 18 2 550 120 1

29 27 69 154 29.1 11 1 0 0 0 3 3 3 3 17 2 600 110

30 23 77 167 27.6 14 1 0 0 0 2 4 4 3 18 2 700 110 2

31 26 66 171 22.6 10 1 0 0 0 1 2 2 2 16 1 570 80

32 27 65 165 23.9 14 1 0 0 0 2 2 2 2 18 2 650 100

33 26 87 167 31.2 18 1 0 0 0 3 4 4 4 17 1 880 120 1

34 26 76 164 28.3 16 1 0 0 0 2 3 3 2 20 2 670 170

35 34 82 174 27.1 15 1 0 0 0 3 3 3 3 22 2 860 120

36 29 65 154 27.4 14 2 1 1 0 2 3 3 3 16 1 670 110 3

37 26 68 164 25.3 11 3 2 1 1 3 4 3 3 17 1 560 80

38 22 76 165 27.9 16 1 0 0 0 2 3 3 3 21 2 800 120

39 23 76 156 31.2 18 1 0 0 0 3 4 4 4 22 1 780 120 1

40 26 58 153 24.8 9 3 2 1 1 2 2 2 2 15 1.2 520 75 4

41 29 75 148 34.2 15 2 1 0 1 3 4 4 3 18 2 680 80 1

42 22 80 154 33.7 16 1 0 0 0 4 4 4 4 16 2.3 890 90 3

43 29 67 165 24.6 10 3 1 1 1 2 3 3 3 17 2 660 100

44 23 75 153 32 14 2 0 0 1 2 3 3 2 17 1.3 880 80 1

45 22 64 160 22.1 11 1 0 0 0 2 2 2 2 19 1.5 760 90

46 26 77 168 27.3 14 1 0 0 0 2 3 4 3 18 2 1100 120

47 29 66 155 27.5 10 3 2 2 0 2 3 3 3 13 1 600 75 4

48 22 67 160 26.2 13 1 0 0 0 2 3 3 2 19 2 850 80

49 25 76 156 31.2 16 1 0 0 0 3 4 4 4 20 2 1200 150

50 26 80 167 28.7 14 1 0 0 0 3 4 4 3 23 1.45 1000 150 1

51 22 76 153 32.5 15 1 0 0 0 2 3 3 3 19 2 900 120

52 33 75 163 26.3 10 1 0 0 0 2 3 3 3 21 1.45 1000 120 2

53 29 68 150 30.2 16 1 0 0 0 3 4 4 3 20 1.3 900 100 3

54 23 55 142 27.3 8 1 0 0 0 2 3 2 2 21 2 800 75 1

55 23 58 152 25.1 10 1 0 0 0 2 2 2 2 20 1.3 850 100

56 31 65 152 28.1 12 1 0 0 0 2 3 4 3 17 1 900 100

57 23 78 169 27.3 14 1 0 0 0 2 4 4 2 19 2 800 75 3

58 23 67 149 30.2 13 1 0 0 0 3 4 3 3 20 2 1000 90

59 22 89 168 31.5 17 1 0 0 0 4 4 4 4 17 1.5 800 80 3

60 26 65 153 27.8 11 1 0 0 0 2 3 3 3 19 2 1000 100

61 22 77 160 30.1 13 2 1 1 0 2 3 3 3 16 1 800 90

62 35 85 166 30.8 16 3 0 0 2 3 4 4 3 13 1 1000 100 1

63 25 77 145 36.6 16 3 1 1 0 3 4 4 4 17 2 800 100 3

64 31 67 162 25.5 11 4 1 2 1 3 3 3 3 18 1 900 150 2

65 27 66 151 28.9 14 1 0 0 0 2 2 2 2 22 2 900 125 2

66 28 78 171 26.7 10 1 0 0 0 2 3 2 2 22 1 1000 100

67 27 66 156 27.1 14 1 0 0 0 2 3 3 3 21 2 1200 150 2

68 23 67 166 24.3 12 1 0 0 0 2 2 2 2 20 1 1000 125

69 31 56 142 27.8 11 2 1 0 1 2 3 4 3 17 1 780 100 1

70 28 67 177 27.5 13 1 0 0 0 1 1 1 1 18 1 740 60

71 24 88 165 32.3 19 1 0 0 0 3 4 4 4 19 2 560 80 1

72 31 59 142 29.3 10 2 1 1 0 2 3 3 2 17 1 800 90

73 26 66 148 30.1 16 1 0 0 0 2 3 3 3 21 2 800 120 1

74 27 65 156 26.7 15 2 1 1 0 2 2 2 2 17 1 890 60

75 23 79 160 30.9 16 2 0 0 1 2 3 2 3 18 1 900 75

76 29 66 150 29.3 12 1 0 0 0 2 3 3 3 16 2 750 150 3

77 28 65 175 21.2 14 1 0 0 0 2 2 2 2 19 2 800 75

78 32 78 160 30.5 16 4 2 1 1 3 4 4 3 18 1 900 100 1

79 25 77 170 26.6 12 3 1 1 1 2 3 3 2 16 1 1100 125 2

80 24 55 143 26.9 12 2 1 1 1 2 3 3 3 18 1 1000 80 1

81 30 67 160 26.2 12 1 0 0 0 2 2 2 2 18 1 900 100

82 25 78 156 32.1 16 1 0 0 0 3 4 4 3 21 2 1100 200 1

83 24 68 166 24.8 11 1 0 0 0 2 2 2 2 19 2 850 200

84 23 67 154 28.3 13 1 0 0 0 2 3 3 3 20 1 990 120

85 25 60 149 27 10 1 0 0 0 2 2 2 2 18 1 700 120

86 24 78 160 30.5 15 1 0 0 0 2 3 3 2 17 2 800 110

87 29 90 162 34.3 14 2 1 1 0 3 4 4 4 16 1 1200 175 3

88 27 76 165 27.9 13 6 1 1 4 3 3 3 3 12 0.45 800 120 4

89 28 88 166 31.9 15 1 0 0 0 3 4 4 3 19 2 1200 110 1

90 23 56 149 25.2 9 3 1 1 1 2 2 2 2 15 1 650 75 4

91 24 75 160 29.3 16 1 0 0 0 2 4 3 3 21 2 850 120 2

92 29 65 159 25.7 10 1 0 0 0 2 2 2 2 18 1.3 800 120

93 23 72 158 28.8 13 1 0 0 0 2 3 3 2 22 1 990 125

94 22 59 150 26.2 14 1 0 0 0 3 3 3 3 16 2 700 150

95 28 67 159 26.5 12 1 0 0 0 3 3 3 3 19 1 900 80

96 26 80 160 31.2 18 2 0 0 1 3 4 4 3 22 1 1000 150 3

97 24 89 156 26.6 17 1 0 0 0 3 4 4 4 20 2 1200 200 2

98 27 59 148 26.9 10 2 1 1 0 2 2 2 2 18 1 600 75

99 33 65 145 30.9 14 1 0 0 0 2 3 3 3 17 2 800 1.2

100 27 67 160 26.2 11 2 1 1 0 3 3 3 3 15 1 800 100 4

101 26 77 167 27.6 15 4 1 1 2 3 3 3 3 16 0.45 900 80

102 25 79 160 30.9 13 2 1 1 0 2 3 3 3 18 1 1000 150 2

103 25 55 141 27.7 11 2 0 0 1 2 3 3 2 18 1 750 110

104 24 66 156 27.1 13 1 0 0 0 2 2 2 2 18 1 900 100

105 24 76 168 26.9 12 1 0 0 0 2 2 2 2 19 1 800 120

106 30 88 165 32.3 14 5 2 2 2 3 4 4 4 12 0.3 920 80 3

107 32 66 152 28.6 15 2 1 1 0 2 3 3 3 17 1 1000 100 1

108 25 66 159 26.1 11 1 0 0 0 2 2 2 2 19 1 800 90 4

109 24 87 167 31.2 15 1 0 0 0 3 4 4 3 21 2 1250 230 3

110 26 67 162 25.5 10 1 0 0 0 2 2 2 2 17 1 770 80

111 29 76 150 33.8 14 2 1 1 0 2 3 3 3 16 0.45 800 140

112 25 67 154 28.3 13 2 1 1 0 2 3 3 3 17 1 900 110

113 25 95 167 34.1 18 1 0 0 0 4 4 4 4 21 2 1300 200 3

114 28 75 156 30.8 16 1 0 0 0 3 3 3 3 20 1 750 110

115 25 66 145 31.4 12 2 1 1 0 2 3 3 3 18 1 900 120 4

116 28 65 156 26.7 14 1 0 0 0 3 3 3 3 18 2 900 100

117 28 66 154 27.8 10 2 1 1 0 2 2 2 2 15 0.45 740 110

118 32 56 143 27.4 12 1 0 0 0 2 3 3 3 19 2 600 100

119 25 70 162 26.7 14 3 0 0 2 3 4 4 3 15 1 780 120 1

120 23 65 152 28.1 16 1 0 0 0 2 3 3 2 18 2 1100 170

121 29 78 166 28.3 13 2 0 0 1 3 3 3 3 14 0.45 800 100

122 29 59 142 29.3 14 1 0 0 0 3 4 4 4 17 1 900 100 1

123 25 67 156 27.5 11 1 0 0 0 3 3 3 3 19 1 750 125

124 30 89 165 32.7 16 1 0 0 0 2 4 3 3 21 1 900 130 1

125 22 65 155 27.1 10 1 0 0 0 3 3 3 3 17 2 700 100

126 24 67 153 28.7 12 3 1 1 1 3 3 3 3 14 1 650 100

127 25 77 159 30.5 15 3 0 0 2 2 4 3 3 17 1 850 120 2

128 27 78 167 28 10 1 0 0 0 4 4 4 4 16 2 800 120 4

129 27 66 145 31.4 14 2 0 0 1 2 3 3 3 19 1 900 100

130 25 87 165 32 18 1 0 0 0 3 4 4 3 18 2 1100 120 3

131 30 76 156 31.2 13 2 0 0 1 2 3 3 3 17 1.3 870 110 1

132 29 68 157 27.8 13 1 0 0 0 2 2 2 2 19 1 750 100

133 29 77 160 30.1 15 1 0

0 3 4 4 3 22 2 1200 130 2

134 23 66 143 32.3 16 2 1 1 0 3 4 4 4 16 1.45 800 120 3

135 25 77 165 28.3 15 1 0 0 0 3 3 3 3 18 1 850 120

136 23 65 142 32.2 12 3 1 1 1 2 3 3 2 14 0.45 600 80

137 30 65 160 25.4 12 3 1 1 1 2 2 2 2 15 0.3 500 75

138 24 71 163 26.7 11 1 0 0 0 3 3 3 3 17 1 1000 120

139 26 76 159 30.1 16 1 0 0 0 3 4 4 3 23 2 1200 150

140 34 67 148 30.6 16 2 1 1 0 3 4 4 4 16 1 800 120 1

141 22 60 149 27 12 1 0 0 0 2 2 2 2 20 2 1000 120 3

142 22 78 158 31.2 18 1 0 0 0 3 4 4 3 22 1 1300 180 3

143 25 67 153 28.6 14 0 0 0 0 2 3 3 3 20 2 1200 150 4

144 26 70 164 26 13 1 0 0 0 3 3 3 3 18 2 700 230

145 27 61 152 26.4 9 4 2 2 1 2 2 2 2 13 1 650 75 4

146 22 90 168 31.9 16 1 0 0 0 3 4 4 4 18 2 1000 120 3

147 24 63 142 31.2 14 1 0 0 0 2 3 4 3 19 1 1200 100

148 24 67 159 26.5 11 2 0 0 1 2 2 2 2 17 0.45 650 100

149 29 59 148 26.9 10 3 1 1 1 2 3 3 3 15 0.45 800 120

150 25 80 160 31.2 16 1 0 0 0 4 4 4 4 20 1 1200 75 1

151 29 65 158 26 10 1 0 0 0 3 3 3 3 21 2 1000 120 3

152 29 67 154 28.3 13 3 1 1 1 2 3 3 3 14 1 750 100 4

153 33 78 160 30.5 14 1 0 0 0 3 4 4 3 18 1 900 100 1

154 22 70 162 26.7 12 1 0 0 0 2 2 2 2 18 1 800 100 4

155 27 78 165 28.7 10 1 0 0 0 3 3 3 3 21 1 1000 110

156 33 78 159 30.9 17 4 2 1 1 3 4 4 3 14 0.3 600 60 4

157 28 68 154 28.7 15 2 1 1 0 2 3 3 3 16 1 700 120

158 31 67 159 26.5 13 1 0 0 0 3 3 3 3 18 2 1000 120 2

159 28 58 149 26.1 11 3 1 1 1 2 2 2 2 15 1 800 75

160 25 79 168 28 14 1 0 0 0 3 4 4 4 22 2 1400 150 2

161 28 66 156 27.1 13 2 1 1 0 2 2 2 2 16 1.3 770 100

162 28 87 165 32 16 2 1 1 0 3 4 4 4 18 1 800 120 1

163 31 68 158 27.2 13 1 0 0 0 3 3 3 3 19 2 780 120

164 25 89 160 34.8 20 1 0 0 0 3 4 4 3 22 2 1200 200 3

KEY TO MASTER CHART

BMI : Body mass index

Wt gain : Weight gain during pregnancy in kilograms

MP I : Mallampati class recorded at 1st time interval

MP II : Mallampati class recorded at 2nd

time interval

MP III : Mallapati class recorded at 3rd

time interval

MP IV : Mallampati class recorded at 4th

time interval

1st stage : Duration of first stage of labour in hours

2nd

stage : Duration of second stage of labour in hours

IV 1st : Amount of intravenous fluids given during 1

st stage of

labour in millilitres

IV 2nd

: Amount of intravenous fluids given during 2nd

stage of

labour in millilitres

Co-morbidities

1- Pregnancy induced hypertensive disorders

2- Gestational Diabetes milletus

3- Hypothyroidism

4- Anaemia.