AN OBSERVATIONAL STUDY ON EFFECT OF HEAD PILLOW, …

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AN OBSERVATIONAL STUDY ON EFFECT OF HEAD PILLOW, SHOULDER

ROLL AND HEAD ROTATION ON RIGHT IJV CALIBER IN PATIENTS

UNDERGOING ELECTIVE SURGERY UNDER GENERAL ANAESTHESIA

Dissertation submitted in partial fulfillment of the requirement of the Tamil Nadu Dr.

M. G. R. Medical University for the M.D Branch X (Anaesthesiology) Examination to

be held in May 2018

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OBSERVATIONAL STUDY ON EFFECT OF HEAD PILLOW, SHOULDER

ROLL AND HEAD ROTATION ON RIGHT IJV CALIBER IN PATIENTS

UNDERGOING ELECTIVE SURGERY UNDER GENERAL ANAESTHESIA

Dissertation submitted to the

THE TAMIL NADU DR. M.G.R MEDICAL UNIVERSITY, CHENNAI

In partial fulfillment of the requirements for the degree of

MASTER OF MEDICINE

IN

ANAESTHESIOLOGY

By

SIVANANDAN A

Register number: 201520360

DEPARTMENT OF ANAESTHESIOLOGY

CHRISTIAN MEDICAL COLLEGE

VELLORE

May 2018

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CERTIFICATE

This is to certify that the dissertation titled “A study on effect of head pillow,

shoulder roll and head rotation on Right IJV caliber in patients undergoing

elective surgery under general anaesthesia” is the bonafide work done by Dr.

Sivanandan A in the Department of Anaesthesiology, Christian Medical College and

Hospital, Vellore in partial fulfillment of the requirements for the degree of M.D.

Anaesthesiology Examination Branch X of the Tamil Nadu Dr. M.G.R. Medical

University, Chennai , to be held in May 2018. This work was carried out under the

guidance of Dr. Chitra S, Associate professor, Department of Anaesthesiology,

Christian Medical College, Vellore.

Dr. Chitra S,

Associate Professor,

Department of Anaesthesiology,

Christian Medical College,

Vellore-632004.

Tamil Nadu.

India.

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CERTIFICATE BY THE HEAD OF THE DEPARTMENT





Hospital, Vellore under the guidance of Dr. Chitra, Associate professor, Department of

Anaesthesiology, Christian Medical College, Vellore.

Dr. Sajan Philip George,

Professor and Head,

Department of Anesthesiology,


Vellore-632004.

Tamil Nadu.

India.

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CERTIFICATE BY THE PRINCIPAL





Hospital, Vellore under the guidance of Dr. Chitra, Associate professor, Department of

Anaesthesiology, Christian Medical College, Vellore.

Dr. Anna. B. Pulimood,

Principal,


Vellore – 632004.

Tamil Nadu.

India.

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DECLARATION CERTIFICATE



elective surgery under general anaesthesia” which is submitted by me in partial

fulfillment towards MD Anaesthesiology examination of The Tamil Nadu Dr. M.G.R

Medical University, Chennai to be held in May 2018 comprises only my original work

and due acknowledgement has been made in text to all material used.

Dr. Sivanandan A

PG Registrar, Department of Anaesthesia,


Vellore 632004,

Tamil Nadu.

India.

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Antiplagiarism software

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ACKNOWLEDGEMENT

I thank God Almighty for giving me the opportunity to do this study and giving me the

grace to complete it successfully.

I acknowledge my deepest sense of gratitude to Dr. Chitra, my guide, for her guidance,

patience, support and encouragement throughout this study.

I would like to thank Dr. Sajan Philip George, Head of the Department of

Anaesthesiology, Christian Medical College for helping me with this study by providing

permission to use the department ultrasound machine. I would also like to thank Dr. Raj

Sahajanandan, Head of Unit 4(Cardiac anaesthesiology), for allowing me use his unit

ultrasound machine.

I would like to thank my statistician Mrs. Rekha for helping me with sample size

calculation, and Ms. Hepsy Chelliah for helping me with the data analysis.

I owe a special thanks to the Anaesthesia technicians who were very helpful in getting

the ultrasound machine to the respective theatre for the study in addition to their busy work

schedule.

I am grateful to my parents who always showed their love and support and were very

helpful in my every endeavor.

Last but not the least; I thank all the patients who were part of this study.

Sivanandan. A

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TABLE OF CONTENTS

TABLE OF CONTENTS ............................................................................................................ 9

1. Introduction ......................................................................................................................... 11

2. Aims ................................................................................................................................... 14

3. Objectives ........................................................................................................................... 16

4. Literature review ................................................................................................................. 18

5. Materials and Methods ........................................................................................................ 37

6. Results ................................................................................................................................ 48

7. Discussion .......................................................................................................................... 75

8. Limitations ......................................................................................................................... 80

9. Conclusion .......................................................................................................................... 82

10. References ......................................................................................................................... 85

11. Annexures .......................................................................................................................... 88

IRB approval letter: .............................................................................................................. 88

Consent form and Patient Information Sheet ........................................................................ 92

Data collection form: ............................................................................................................. 96

Sign: ....................................................................................................................................... 96

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INTRODUCTION

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1. Introduction

Central venous catheter is required for managing patients posted for certain

surgeries and a variety of clinical conditions. It is used for haemodynamic monitoring

as well as administration of nutrition and drugs which are not safe for administration

via peripheral venous catheters.

Various sites are available for central venous cannulation like Internal jugular

vein, Subclavian vein and Femoral vein. A review published by NEJM reported

complication rate of 15 percent. Of these mechanical complications were reported as 5-

19 percent. Mechanical complications include arterial puncture, haematoma, nerve

injury, haemothorax and pneumothorax. Internal jugular vein cannulation is associated

with low rate of severe mechanical complications compared to subclavian. Chance of

infection is high with femoral central line. Left internal jugular vein cannulation is

associated with more complications than right internal jugular vein cannulation.

Because of the above reasons and ease of access, the right internal jugular vein is

preferred as the site for central venous cannulation.

The success rate of right internal jugular vein cannulation was found to be

related to its diameter. Several methods have been used to increase the diameter of the

internal jugular vein like head rotation, trendelenberg tilt, valsalva manoeuver,

shoulder roll, head pillow, neck extension, passive leg raise, hepatic compression and

positive end expiratory pressure on the ventilator. Trendelenberg tilt has been well

established as a method to increase the right internal jugular vein diameter and is

recommended in practice guidelines published by American society of

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Anaesthesiologists. Various studies have shown that a simple technique of using head

pillow was associated with significant increase in the right internal jugular vein

diameter. Head rotation to opposite side is required to improve exposure for internal

jugular vein cannulation. Studies have shown that neck rotation to less than 45 degree

improves exposure with less overlap between internal jugular vein and carotid as

compared to greater degrees of rotation. There is also a practice of using shoulder roll

for right internal jugular vein cannulation. Studies have shown that it decreases the

overlap between the carotid and internal jugular vein but also decreases the antero-

posterior diameter of the internal jugular vein.

In our setting we routinely use Trendelenberg position for Right Internal Jugular Vein

cannulation. We also prefer head rotation towards the left to improve ease of access.

But head pillow is not used by many as it causes flexion and restricts access for

cannulation. But studies have shown that head pillow increases the diameter of Right

Internal Jugular Vein. We propose to study the simple techniques of using head pillow,

shoulder roll and neck rotation to find their effect on size of the right internal jugular

vein diameter and its overlap with carotid. As these simple techniques can be used in

any setting, the study will help in better positioning of the patient which will be useful

in developing countries like India, where ultrasound is not available everywhere for

guidance during internal jugular vein cannulation.

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AIMS

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1. Aims

To assess the variations of right internal jugular vein in patients based on

position using ultrasound to find optimal position for right internal jugular vein

cannulation.

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OBJECTIVES

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2. Objectives

• To assess changes in Right Internal Jugular Vein diameter based

on position using ultrasound to determine optimal patient position

in which Internal Jugular Vein diameter is the largest.

• To assess the degree of overlap between Right Internal Jugular

Vein and Carotid based on position using ultrasound to find the

optimal position in which the overlap is minimal.

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LITERATURE REVIEW

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4. Literature review

Central venous access is defined as placement of a catheter such that the catheter

is inserted into a venous great vessel. These include internal jugular vein, subclavian

vein, superior vena cava, brachiocephalic veins, inferior vena cava, iliac veins and

common femoral vein(1).

Central venous catheters help in haemodynamic monitoring which may not be

accurately measured by non-invasive means. It also helps in administering medication

and nutritional support which cannot be given safely through a peripheral venous

catheter. Right internal jugular vein is one of the most commonly used sites for central

venous access. It has a predictable location, ease of access during surgery, enters right

atrium directly and a high success rate(2). It has the lowest incidence of mechanical

complications compared to subclavian and femoral access(3,4). Internal jugular and

subclavian catheterization is associated with lower rate of blood stream infections

compared to femoral catheterization(3,5).

Central venous cannulation is associated with complications even under

ultrasound guidance. In patients with central line the rate of complications is around 15

percent. It is divided into mechanical(5 – 19%), infectious(5 – 26%) and thrombotic(2 –

26%)(6).

Mechanical complications include arterial puncture, haematoma, nerve injury,

haemothorax and pneumothorax. Internal jugular vein cannulation is associated with

low rate of severe mechanical complications compared to subclavian(7). Left internal

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jugular vein cannulation is associated with more complications than right internal

jugular vein cannulation(8). Anterior approach for IJV is the better technique with

success more on the right(9).

Because of the above reasons and ease of access, the right internal jugular vein

is preferred as the site for central venous cannulation.

Anatomy of the Internal jugular vein:

Internal jugular vein is formed by the union of inferior petrosal and sigmoid

dural venous sinuses in or just distal to the jugular foramen. It descends in the carotid

sheath with the internal carotid artery. The Vagus nerve lies between the two. It

descends down between the two heads of the sternocleidomastoid to the thorax where it

joins the subclavian vein to form the brachiocephalic vein.

It receives blood from inferior petrosal sinus, pharyngeal veins, facial vein,

lingual vein, superior and middle thyroid vein.

Its relationship to carotid varies at different levels. It lies anterior, anterolateral

and lateral to the carotid at C2, C3 and C4 vertebrae respectively.

Its anterior relations include spinal root of accessory nerve at the upper third,

lower root of Ansa cervicalis at the middle third and it is crossed in the lower third by

Sternocleidomastoid muscle and tendon of Omohyoid muscle.

Its posterior relations include lateral mass of C1, middle scalene muscle, anterior

scalene muscle and pleura of lung apices.

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The Internal Jugular Vein can be identified by using the Sedillot’s triangle as the

surface landmark. It includes the Sternal head of Sternocleidomastoid on the medial

aspect, the Clavicular head of Sternocleidomastoid on the lateral aspect and the superior

border of the medial third of the clavicle at the base. Internal Jugular Vein can be

cannulated by a skin puncture at the superior aspect of this triangle.

Figure 1: RIGHT INTERNAL JUGULAR VEIN SURFACE ANATOMY

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Figure 2: Right internal jugular vein anatomy

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Ultrasonography:

Ultrasound in physics refers to frequencies of sound waves above 20,000 Hz.

Ultrasonography is a diagnostic imaging technique utilizing reflected high-

frequency sound waves to delineate, measure, or examine internal body structures or

organs. Medical ultrasound frequencies range from 2 to 15 MHz although higher

frequencies may be used sometimes(10).

The basic principle requires sending pulse of ultrasound into the body and

waiting for an echo to return. These returning echoes are processed to produce an image

of the internal structures.

A-scan or amplitude scan was the mode in original scanner. The reflections were

simply displayed on the screen of the cathode ray oscilloscope. There is a peak on the

trace when there is reflection from tissue layers. The difference in acoustic impedance

of tissues determines the amplitude of the peaks. There is also variation in absorption of

sound by different tissues which leads to change in output

In B-Scan the amplitude of each returning signal is not simply displayed on a

graph or CRO screen. The brightness of the reflected signal depends on the amplitude.

B is for brightness in the name B-scan. The ultrasound wave passing through different

tissues will give rise to series of bright spots depending on the amplitude of reflection.

The largest amplitude gives rise to a bright spot whereas the smallest amplitude will

give rise to a black spot. Even the areas that do not give rise to any spike will appear

black. The amplitudes in between will give rise to various shades of grey.

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Transducer probe is the part of the ultrasound machine that plays an important

role by producing as well as receiving the ultrasound waves. It is based on the

Piezoelectric effect which is production of electric polarity or electricity when

mechanical stress is applied to certain crystals and also the converse effect of

generation of mechanical stress when they are subject to electric field. The Transducer

probe has a number of piezo-electric crystals that have the ability to vibrate to produce

sound of a particular frequency when electricity is passed through them. This is how

ultrasound is produced. Conversely when sound or pressure waves hit the crystals they

emit electric currents. Therefore the same crystals can be used to emit and receive

sound waves. The ultrasound waves sent from the transducer propagate through tissues

and reflect back. This information is further processed to form the ultrasound image on

the screen(11).

Transducers are available in many shapes and sizes. The shape of the probe

determines its field of view, and the frequency of the emitted sound waves determines

how deep the sound waves penetrate and the resolution of the image. The three basic

types of probe used are linear, curvilinear and phased array (Figure 3). The ultrasound

images obtained by a linear transducer will be rectangular in shape while those obtained

by curvilinear will be wider with increased depth (Figure 4).

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Figure 3. Right to left: Phased array probe, Linear probe and curvilinear probe

Figure 4: Different types of sectors of ultrasound probes

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The straight linear array probe is designed for superficial imaging. The

arrangement of crystals is linear within a flat head and a straight parallel line of sound

waves is produced. It has better resolution and less penetration due to the high

frequency (5- 13 MHz). Hence this probe is used in imaging superficial structures and

ultrasound guided procedures like central venous cannulation(12).

Ultrasound Doppler blood flow detector was used to identify the Internal jugular

vein location by J I Ullman in 1978 (13).

Real time ultrasound guidance was used in 1986 by Yonei et al for percutaneous

puncture of Internal jugular vein and catheterization. They used a 5 MHz ultrasound

transducer. The head was turned to opposite side by 45 degree and povidone iodine was

used as acoustic coupling medium. Longitudinal view of the Internal jugular vein was

used for puncture and catheterization(14).

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INDICATIONS AND CONTRAINDICATIONS:

Indications for central venous cannulation:

• Central venous pressure monitoring

• Pulmonary venous catheterization and monitoring

• Transvenous cardiac pacing

• Temporary hemodialysis

• Drug administration

o Concentrated vasoactive drugs

o Hyper alimentation

o Chemotherapy

o Agents irritating to peripheral veins

o Prolonged antibiotic therapy

• Rapid infusion of fluids

o Trauma

o Major surgery

• Aspiration of air emboli

• Inadequate peripheral venous access

• Sampling site for repeated blood testing

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Contraindications for central venous cannulation:

• No absolute contraindications

• Relative contraindications

o Distorted local anatomy

o Skin infection at cannulation site

o Scarring or mass at site

o Coagulopathy

o Obstructed vein

Complications of central venous cannulation:

• Mechanical

o Vascular injury

§ Arterial

§ Venous

§ Cardiac tamponade

o Respiratory compromise

§ Pneumothorax

§ Airway compression from hematoma

o Nerve injury

o Arrhythmias

• Thromboembolic

o Venous thrombosis

o Pulmonary embolism

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o Arterial thrombosis and embolism

o Catheter or guide wire embolism

• Infectious

o Insertion site infection

o Catheter site infection

o Bloodstream infection

o Endocarditis

Technique of Right Internal jugular vein cannulation:

Seldinger technique is used for placement of the central venous catheter. The

catheter insertion site is cleaned and draped. Identify the IJV then use a wide bore

introducer needle on a 5 cc disposable syringe. Advance the needle gradually aspirating

for venous blood. Venous entry leads to aspiration of blood in the needle. Disconnect

the syringe and occlude the needle hub to avoid air being drawn by the negative

intrathoracic pressure. Then insert the blunt tipped guide wire through the introducer

needle. Remove the introducer needle holding the guide wire in place. The insertion site

is enlarged with a stab using 11 size blade or using a dilator. Thread the dilator over the

guide wire and hold the guide wire during inserting and removing the dilator. Finally

the central venous catheter is threaded over the guide wire withdrawing it until it

protrudes from the infusion port of the catheter before placing the catheter at the desired

depth and the guide wire is removed.

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Seldinger technique:

It was described by Sven Ivar Seldinger in 1953. It was initially used for catheter

method of angiography. It consists of the following steps

• The vessel is punctured with a needle.

• Then a guide wire is introduced through the needle into the vessel.

• The needle is withdrawn and guide wire is left insitu.

• The catheter is then threaded over the guide wire making sure the tip of

the catheter is protruding from the free end of the catheter so that it can be

held preventing accidental loss of the guide wire into the vessel

• The catheter is pushed to the desired position and the guide wire is

removed.

There are two techniques to access the Right IJV

• Landmark guided

• Ultrasound guided

Landmark guided technique:

Three approaches have been described for the Right IJV cannulation using

landmark technique.

• Anterior approach

• Central approach

• Posterior approach

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Anterior approach:

The IJV is located in the Sedillot’s triangle.

It includes the Sternal head of Sternocleidomastoid on the medial aspect, the

Clavicular head of Sternocleidomastoid on the lateral aspect and the superior border of

the medial third of the clavicle at the base.

The IJV is accessed at the anterior border of the sternal head of the

sternocleidomastoid muscle, just lateral to the carotid at an angle of 45 -60 degree. The

needle is directed towards the ipsilateral nipple. The vein should be entered within 3 – 5

cm.

Central approach:

IJV is accessed at the apex of the Sedillot’s triangle formed by Sternal head of

Sternocleidomastoid on the medial aspect, the Clavicular head of Sternocleidomastoid

on the lateral aspect and the superior border of the medial third of the clavicle at the

base.

The needle is directed slightly lateral and caudad towards the ipsilateral nipple at

an angle of 30-40 degrees to the skin. The vein should be entered within 1.5 – 3cm.

Posterior approach:

IJV is accessed by the needle inserted along the posterior border of the

sternocleidomastoid muscle just above the site where the external jugular vein crosses

that border. It is located at the middle of the line between sternal head of clavicle and

the mastoid process.

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Direct the needle at 30 – 45 degree angle to the skin and advance medially and

inferiorly towards the suprasternal notch. The vein should be entered within 5 cm.

If external jugular vein is not visualized then the needle is inserted along the

posterior border at the junction of middle and lower third.

Ultrasound guided technique:

The ultrasound is placed on the skin to identify the target vessel. Both the Right

IJV and Carotid are visualized as two circular black structures. They are differentiated

based on the anatomical position and compressibility. The Internal jugular vein is

mostly anterolateral or anterior to the carotid and varies in size with respiration. Internal

jugular vein is easily compressed by pressure and valsalva can increase the diameter.

Both long axis and short axis views can be used. The long axis technique has the

advantage of visualizing the whole length of the needle. But the short axis view is

commonly used as both the right IJV and carotid are visualized simultaneously. Short

axis view is easier to learn. In short axis view the vein in positioned in the center of the

screen before the vessel is punctured. Then the Seldinger technique is used to complete

the cannulation.

Longitudinal view can be used to confirm intravenous placement before

cannulation by visualizing the guide wire in the internal jugular vein.

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Methods to improve success rate of Right IJV cannulation and reduce

complications:

It has been shown that the success rate of Right IJV cannulation was directly

related to its size(15). A study by Gordon et al showed that there was significant

correlation between first pass success and IJV diameter.

Several methods have been used to increase the diameter of the internal jugular

vein like head rotation, trendelenberg tilt, valsalva manoeuver, shoulder roll, head

pillow, neck extension, passive leg raise, hepatic compression and positive end

expiratory pressure on the ventilator(16–18,18–20).

Trendelenberg tilt has been well established as a method to increase the right

internal jugular vein diameter and is recommended in practice guidelines published by

American society of Anaesthesiologists(1,17,21–23). A study by Clenaghan et.al has

shown that even a 10 degree Trendelenberg tilt is effective in increasing the diameter of

the Right IJV. The study was done on healthy volunteers with equal representation by

both sexes. The mean diameter showed an increase from 13.5 mm to 15.5 mm with

Trendelenberg tilt of 10 degree. The mean diameter was 15.5 mm, 16.4 mm and 16.7

mm with Trendelenberg tilt of 15, 25 and 30 degrees respectively(21). A study by

Marcus et.al also showed a 39.4% increase in cross sectional area of right IJV when a

20 degree Trendelenberg tilt was used. This study was carried out in anaesthetized

patients(20). In a study by Parry et al the mean diameter of the Right IJV was 9.2 +/-

2.06 mm when volunteers were placed supine with head in the midline. It increased to

12.1 +/- 2.34 when they were placed in a 15 degree Trendelenberg tilt. In a study on

100 volunteers belonging to ASA grade I and II by Dhulkhed et.al the mean diameter of

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Right IJV was 12.7 +/- 2.02 mm when volunteers were placed in supine position with

head on midline . It increased to 15.8 +/- 2.6 mm when they were placed in 15 degree

Trendelenberg tilt and head on a small pillow. Thus it is clear that Trendelenberg tilt

increases the diameter of right IJV in both awake as well as anaesthetized individuals.

A small head pillow was associated with an increase in IJV diameter from 9.2

+/- 2.18mm to 10.6 +/- 2.16mm in a study by Parry et al. Another study by Dhulkhed et

al also showed that a small pillow under the head caused significant increase in the IJV

diameter from a mean of 12.7+/- 2.02mm to 13.3+/-2.02mm. A study by Armstrong et

al showed that mean diameter of IJV increased from 11.5mm to 12.1 mm with head

pillow. Thus head pillow has been shown to be a useful technique in improving success

of IJV cannulation(17,22,23).

Carotid artery injury is a serious complication of IJV cannulation. This is due to

the overlap between the IJV and Carotid. Various studies have shown that head rotation

to opposite side increases the degree of overlap but head rotation to opposite side is

required to improve exposure for internal jugular vein cannulation. Hence IJV

cannulation using landmark technique may lead to carotid artery puncture as head is

rotated to the opposite side for exposure. Studies have shown that neck rotation to less

than 45 degree improves exposure with less overlap between internal jugular vein and

carotid as compared to greater degrees of rotation. Ultrasound guidance is

recommended (24–28). A study by Lieberman et.al assessed the risk of IJV and

Carotid puncture by simulating needle puncture using ultrasound in different degrees of

head rotation. They simulated a needle passing from the tip of the ultrasound using

depth gauge to indicate central 1.5 mm of the ultrasound image. The intersection of this

1.5 mm band and any part of IJV inner lumen and/or Common Carotid was defined as a

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hit. It was found that risk of Carotid puncture was less than 10% for head rotation less

than 45 degree. They also reported high risk of Carotid puncture in patients with high

BMI and BSA when head was rotated to 45 and 60 degree. They concluded that head

rotation of no more than 30 degree in high BMI and BSA patients will reduce chance of

Carotid puncture and improve IJV contact. Whereas they suggested head rotation of 60

degrees can be used in patients with low BMI or BSA(24). Shoulder roll reduces the

overlap between the Right IJV and the right Carotid. In a study on volunteers by WK

Chang et al there was a decrease in overlap between carotid and right IJV from 55.3 +/-

25% to 28.7 +/- 28% when a 5 cm shoulder roll was used.

Ultrasound guidance is associated with higher success rate, low complication

rate and faster access time. Denys et al did a study to compare the ultrasound guided

cannulation technique with external landmark technique on Right IJV and found 100%

success with ultrasound guided technique compared to 88.1% with landmark guided

technique. First pass success was 78% with ultrasound and 38% with landmark guided

technique. Average access time was also much lower when using ultrasound (9.8 s)

compared to landmark technique (44.5s). Complication rate for Carotid puncture,

brachial plexus irritation and haematoma was 1.7%, 0.4% and 0.2 % respectively in

ultrasound guided technique vs. 8.3%, 1.7% and 3.3% in the landmark guided

technique(29). Even in the ICU setting, the use of ultrasound for central venous

cannulation was associated with a higher success rate. Slama et.al compared ultrasound

guided technique to landmark technique and found 100% success with ultrasound

guidance vs. 76% in the landmark technique in an ICU setting (30).

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A meta-analysis was done by Hind et.al which compared the landmark method

with real time ultrasound for cannulation of the internal jugular vein showed there was

a lower failure rate when ultrasound guidance was used.

Cochrane review by Brass et.al showed that overall complication rate was

reduced by 71% when ultrasound was used and arterial puncture was reduced by 72%.

The chance of first pass success was increased by 57% and chance of haematoma

formation was decreased by 73% when ultrasound was used. There was a 30.52 second

reduction in time taken for successful cannulation with ultrasound(31).

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MATERIALS AND METHODS

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5. Materials and Methods

This study included all consenting patients posted for surgery under general

anaesthesia in main operation theatre. Informed consent was obtained by the

investigator prior to the surgery.

Setting:

The study was done in the main operation theatre complex, Christian Medical

College and Hospital, Vellore, Tamil Nadu.

Inclusion criteria:

• ASA I and II patients posted under general anaesthesia in main theatre

complex.

• Patients of both gender

• Age more than 18 years

Exclusion criteria:

• Patient refusal to participate in the study

• ASA III or higher

• Diseases involving the cervical spine

• Patients with limitation of neck movement or pain

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• Previous neck or vascular surgery involving right internal jugular vein

• Neck scars or burns

• Recent Right IJV cannulation

• Patient with surgical conditions in the neck. (e.g. Thyroid lesions) which will

affect Right IJV diameter

Sample size:

For the sample size calculation, the statistical input was taken from the

following reference article “An observational study of change in diameter of right

internal jugular vein with various body positions in volunteers with the aid of 2-

dimensional ultrasonography

Formula:

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Single Mean - Paired t-test:

Pre-test mean 13.3

Post-test mean 12.7

Standard deviation in Pre-test 2.34

Standard deviation in Post-test 2.02

Effect size 0.275229358

Power (%) % 80

Alpha Error 5

1 or 2 sided 2

Required sample size 106

The sample size was calculated using n Master software version 2.0. The study required

totally 106 patients to study the changes in Right IJV diameter based on position using

ultrasound to determine optimal patient position in which IJV diameter is largest.

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Quantitative variable:

For continuous data such as age, the descriptive statistics n, Mean, SD, Median,

Minimum and Maximum was presented.

Statistical Analysis:

For continuous data such as age, the descriptive statistics n, Mean, SD, Median, IQR,

Minimum and Maximum was presented. For categorical data, the number of patients

and percentage was presented. Based on the normality of data, the parametric paired t

test or non-parametric Wilcoxon signed rank test was applied to the data. The Chi-

square or Fisher’s exact test was applied to the data.

P-values reported as specified by the statistical software used, at least up to four

decimal places. P-values less than 0.0001 was reported as provided by statistical

software (e.g. '<0.0001'). All tests will be two-sided at α=0.05 level of significance.

Other statistical tests were carried as it was deemed. All statistical analysis was done

using SPSS software version 17.0 or later.

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Methodology:

All consenting patients posted for surgery in the operation theatre were recruited.

Informed consent was obtained by the investigator prior to surgery.

Patient premedication and anaesthesia was based on standard protocol. After

intubation, patients were put on pressure controlled ventilation. Standard setting of

8ml/kg tidal volume, 5 peep and a respiratory rate of 15 was set. Respiratory rate was

adjusted to achieve the desired ETCO2 by the in charge anaesthetist.

Anaesthetized patients were placed in the following positions before the

measurements were made.

Position 1 (P1):

Patient placed supine on the operating table with 15 degree Trendelenberg

tilt and head rotated to the left by 30 degree. No head pillow or shoulder roll was

used.

Position 2 (P2):


tilt and head rotated to the left by 30 degree and head placed on a small pillow of

4 cm.

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Position 3 (P3):


tilt and head rotated to the left by 30 degree along with placement of a shoulder

roll of 5 cm.

The measurements were made using ultrasound probe placed perpendicular to

vessels at the level of cricoid in the Sedillot’s triangle formed by the sternal and

clavicular head of the right sternocleidomastoid with medial third of clavicle inferiorly.

A mark was placed at this point so measurements are done at the same location.

The medial edge of the probe was aligned with the medial wall of Right Carotid

during the measurement. Measurements were taken at end expiration to maintain

uniformity. The following measurements were made in all 3 positions

• Right internal jugular vein (RIJV) transverse and antero-posterior

diameter

• Right Carotid artery transverse diameter

• Percentage of overlap between both

RIJV overlap of Carotid x 100

Carotid artery diameter

43

The ultrasound probe was placed gently on the site to prevent unwanted

compression of the vein. The vein and artery were identified based on the anatomical

position, compressibility and pulsation.

The angle of head rotation was based on position of tip of nose to neutral

position and measured using a protractor and scale.

The patient was placed for 30 seconds in each position before the measurements

were taken. All measurements were made with High frequency vascular probe.

44

Diagrammatic algorithm

106 patients who fulfilled inclusion criteria were invited to the study

Informed consent was taken by the investigator before the surgery

Standard anesthetic protocol was followed

Patients were positioned in the following ways.

Position1 : Supine on the operating table with 15 degree Trendelenberg tilt and head turned towards the left by 30 degree

Position 2: Supine on the operating table with 15 degree Trendelenberg tilt, head turned towards the left by 30 degree and head placed on a pillow of 4 cm

Position 3: Supine on the operating table with 15 degree Trendelenberg tilt and head turned towards the left by 30 degree with a Shoulder roll of 5 cm

Right IJV diameter, Right Carotid diameter and Right IJV overlap with carotid were measured

Data analysed using SPSS

45

Measurements made using ultrasound

A – Transverse diameter of Right IJV

B – Anteroposterior diameter of Right IJV

C – Transverse diameter of Right Carotid

D – Right IJV and Right Carotid overlap

A

B

C

D

Rt IJV

Rt Carotid

46

Sample Ultrasound image:

A – Transverse diameter of the Right IJV

B – Anteroposterior diameter of the Right IJV

C – Transverse diameter of the Carotid

F – Overlap between Right Carotid and Right IJV

47

RESULTS

48

6. Results

Demographic and clinical characteristics

In our study a total of 106 patients were included. Out of them 57 were

male and 49 were female patients which shows a good distribution among the 2

sexes.

57

49

No of pa'ents

Male

Female

49

The mean age of the participants was 46 years and the range was from 19 years

to 76 years.

The mean height of the participants was 160 cm and the range was from 143 cm

to 179 cm.

The mean BMI of the participants was 24.47 kg/m2 and the range was from

11.90 kg/m2 to 38.80 kg/m2.

DEMOGRAPHIC DATA OF STUDY

Variable

Total no of patients

Mean

SD

Minimum

Maximum

Age

106

46.11

12.54

19

76

Height

106

160.61

8.01

143

179

Weight

106

62.99

11.91

26

96

BMI

106

24.47

4.61

11.90

38.80

50

The main objective of our study was to find the position in which the diameter of

the Right IJV is maximum. We also wanted to find the position in which the overlap

between the Right Carotid and Right IJV is least.

Positions used in the study

Position 1 (P1)


tilt and head rotated to the left by 30 degree. No head pillow or shoulder roll was

used

Position 2 (P2)


tilt and head rotated to the left by 30 degree and head placed on a small pillow.

Position 3 (P3)


tilt and head rotated to the left by 30 degree along with placement of a shoulder

roll.

51

Mean Transverse diameter of the Right IJV

The mean transverse diameter of the Right IJV in patients placed in

position 1 was 18.7mm with a standard deviation of 3.9mm.


position 2 was 18.7 mm with a standard deviation of 4mm.



A paired T-test was run between position 1 and position 3 which showed

that there was a statistically significant difference of 1.5mm with 95%

confidence interval of 1 to 1.9 mm. t(106) = 7.602, p < 0.0005.

The mean diameter was the same in position 1 and position 2. There was

no statistically significant difference. t(106) = 0.207, p > 0.0005.

52

Mean Transverse diameter of Right IJV

Position 1: Patient placed supine with 15 degree Trendelenberg tilt and head

rotated to the left by 30 degree


rotated to the left by 30 degree with head placed on a pillow


rotated to the left by 30 degree along with placement of a shoulder roll.

18.7 18.7

17.2

16

16.5

17

17.5

18

18.5

19

Posi5on 1 Posi5on 2 Posi5on 3

Mean Transverse diameter(mm)

Mean Transverse diameter

53

Comparison of incidence of maximum transverse diameter of right IJV among the

3 positions

In our study, 53 (n = 106) patients had the maximum anteroposterior

diameter in position 1, which is 50 % of the study population.

In position 2, the maximum diameter was found in 39 patients, which is

36.79 % of the study population.

The incidence of maximum diameter was least when using a shoulder roll

i.e. position 3. Only 11 patients of the study population in position 3 had the

maximum diameter, which is 10.38 %.

54

Comparison of incidence of maximum transverse diameter of Right IJV in the

three positions

Frequency

IJVT – Transverse diameter of Right IJV in position 1

IJVHT – Transverse diameter of Right IJV in position 2(Head pillow)

IJVST – Transverse diameter of Right IJV in position 3(Shoulder roll)

53

39

11

3

0

10

20

30

40

50

60

IJVT IJVHT IJVST IJVT+IJVST

Frequency of maximum diameter

Frequency of maximum diameter

55

Comparison of incidence of maximum transverse diameter of Right IJV in the three positions

Percentage

IJVT – Transverse diameter of Right IJV in position 1

IJVHT – Transverse diameter of Right IJV in position 2(Head pillow)

IJVST – Transverse diameter of Right IJV in position 3(Shoulder roll)

50

36.79

10.38

2.83

0

10

20

30

40

50

60

IJVT IJVHT IJVST IJVT+IJVST

Percentage of maximum diameter

Percentage of maximum diameter

56

Mean anteroposterior diameter of the Right IJV

The mean anteroposterior diameter of the Right IJV in patients placed in



position 2 was 13.7 mm with a standard deviation of 2.7mm.



A paired T-test was run between position 1 and position 3 which showed

that there was a statistically significant difference of 2.6mm with 95%

confidence interval of 2.2 to 3.0 mm. t(106) = 12.464, p < 0.0005

There was no statistically significant difference between position 1 and

position 2. t(106) = 1.244, p > 0.0005.

57

Mean anteroposterior diameter of the Right IJV






rotated to the left by 30 degree along with placement of a shoulder roll.

13.9 13.7

11.3

0

2

4

6

8

10

12

14

16


Mean Anteroposterior diameter (mm)

Mean Anteroposterior diameter

58

Incidence of maximum anteroposterior diameter of Right IJV in the three

positions

In our study 53 patients (n = 106) had maximum anteroposterior diameter in

position 1 which is 50% of the study population.

In position 2, the maximum diameter was found in 47 patients , which is 44.34%

of the sample size.

The incidence of maximum diameter was least when using a shoulder roll i.e.

position 3. Only 4 patients had the maximum diameter in position 3 (3.77 %)

59

Comparison of incidence of maximum anteroposterior diameter of the Right IJV

in the three positions

Frequency

IJVAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 1

IJVHAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 2

IJVSAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 3

53

47

4 2

0

10

20

30

40

50

60

IJVAP IJVHAP IJVSAP IJVAP+IJVHAP

Largest AP diameter frequency

Largest AP diameter frequency

60

Comparison of incidence of maximum anteroposterior diameter of the Right IJV

in the three positions

Percentage

IJVAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 1

IJVHAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 2

IJVSAP – Incidence of maximum anteroposterior diameter of Right IJV in Position 3

50

44.34

3.77 1.89

0

10

20

30

40

50

60

IJVAP IJVHAP IJVSAP IJVAP+IJVHAP

Largest AP diameter percentage

Largest AP diameter percentage

61

Mean overlap percentage between Right IJV and Right Carotid

The mean of the overlap percentage between the Right IJV and Right

Carotid in patients placed in position 1 was 49.41%.


Carotid in patients placed in position 2 was 50.97%


Carotid in patients placed in position 3 was 35.70%.

A paired T-test run between position 1 and position 3 showed that there

was a statistically significant difference of 13.71 % with 95% confidence

interval of 8.92 % to 18.50%. t(106) = 5.679, p < 0.0005.

There was no statistically significant difference between position 1 and

position 2. t(106) = -0.672, p >0.0005.

62

Mean overlap percentage between Right IJV and Right Carotid





Position 3: Patient placed supine with 15-degree Trendelenberg tilt and head

rotated to the left by 30 degree along with placement of a shoulder roll

49.41 50.97

35.7

0

10

20

30

40

50

60


Mean Caro'd overlap percentage

Mean Caro5d overlap percentage

63

Comparison of incidence of Overlap percentage between Right IJV and Right

Carotid in the three positions

In our study we found that the overlap percentage was minimal when patient was

positioned with a shoulder roll i.e. position 3. The least overlap was found in position 3

in 52 patients (n=106), which is 49.06 percentage.

Frequency

OP – Incidence of minimum overlap of Carotid and Right IJV in Position 1

OPH – Incidence of minimum overlap of Carotid and Right IJV in Position 2

OPS – Incidence of minimum overlap of Carotid and Right IJV in Position 3

14 10

52

6 4 5

15

0

10

20

30

40

50

60

Least Overlap frequency

64

Comparison of incidence of Overlap percentage between Right IJV and Right

Carotid in the three positions

Percentage

OP – Incidence of minimum overlap of Carotid and Right IJV in Position 1

OPH – Incidence of minimum overlap of Carotid and Right IJV in Position 2

OPS – Incidence of minimum overlap of Carotid and Right IJV in Position 3

13.21 9.43

49.06

5.66 3.77 4.72

14.15

0

10

20

30

40

50

60

Least overlap percentage

65

We also did analysis to see if there was any correlation between the diameter of

the Right IJV and the Height, Weight and BMI of the patient.

Correlation between transverse diameter of the Right IJV and Height

There was no statistically significant correlation between transverse diameter of the

Right IJV and height in the study population as shown in the scatter plot above.

p-value 0.67

Correlation value (r) 0.04

66

Correlation between transverse diameter of the Right IJV and Weigh

There was no statistically significant correlation between transverse diameter of the

Right IJV and weight in the study population as shown in the scatter plot above.

p-value 0.18


67

Correlation between transverse diameter of the Right IJV and BMI

There was no statistically significant correlation between the transverse diameter of the

Right IJV and BMI in the study population as shown in the scatter plot above.

p-value 0.25


68

Correlation between the Anteroposterior diameter of Right IJV and Height

There was no statistically significant correlation between the anteroposterior diameter

of the Right IJV and height in the study population as shown in the scatter plot above.

p-value 0.88

Correlation value (r) -0.014

69

Correlation between the Anteroposterior diameter of Right IJV and Weight

There was a statistically significant correlation between the anteroposterior diameter of

the Right IJV and weight in the study population as shown in the scatter plot above.

p-value 0.0013

Correlation factor (r) 0.308

70

Correlation between the Anteroposterior diameter of Right IJV and BM

There was a statistically significant correlation between the anteroposterior diameter of

the Right IJV and BMI in the study population as shown in the scatter plot above.

p-value 0.0009

Correlation factor (r) 0.318

71

Correlation between the Carotid overlap with Right IJV and Height

There was no statistically significant correlation between the overlap percentage of

Right Carotid and Right IJV with height in the study population as shown in the scatter

plot above.

p-value 0.32

Correlation value (r) -0.097

72

Correlation between the Carotid overlap with Right IJV and Weight


Right Carotid and Right IJV with weight in the study population as shown in the scatter

plot above.

p-value 0.42


73

Correlation between the Carotid overlap with Right IJV and BMI


Right Carotid and Right IJV with BMI in the study population as shown in the scatter

plot above.

p-value 0.16


74

DISCUSSION

75

7. Discussion

Central venous access plays an important role in administration of

vasoactive drugs, haemodynamic monitoring as well as transvenous cardiac

pacing. In some cases it is used for administration of fluids and blood products

where peripheral venous access cannot be obtained.

The Right Internal jugular vein is the most commonly used site for central

venous access. It is selected because of its predictable location, ease of access,

high success rate and enters right atrium directly.(2)

This study was done to find which position will help in improving the

success of Right IJV cannulation and also reduce the complications associated

with the procedure. The diameter of the Right IJV and Carotid overlap with IJV

was measured using ultrasound in three different positions in all patients.

It was shown by Gordon et al that larger the diameter of the Right IJV,

greater will be the success of first pass cannulation.(15) The main purpose of our

study was to find the position in which Right IJV diameter is the largest. A study

by Armstrong et al showed that mean diameter of IJV increased from 11.5mm

to 13.1 mm even with 10 degree of Trendelenberg tilt. Whereas head pillow

showed an increase in mean diameter to 12.1 mm.(17) In a study by Dhulkhed

et al there was an increase in mean diameter from 12.7+/-2.02mm to 13.3+/-2.4

mm when a head pillow was used and to 15.8+/-2.6 when 15 degree

Trendelenberg tilt was used(23).

76

In our study the mean transverse diameter of the Right IJV was 18.7 mm

in both position 1 and position 2. There was no significant difference in diameter

between the 2 positions. This is contradictory to previous studies which have

shown that use of head pillow increases the Right IJV diameter.(17,22,23)

There was a statistically significant reduction in mean transverse diameter

to 17.2 mm in position 3. This is similar to previous studies which show that

shoulder roll decreases the Right IJV diameter(32)

Similarly in our study the mean antero-posterior diameter of the Right

IJV were 13.9 mm in position 1 and 13.7 mm in position 2. There was a

statistically significant reduction in mean diameter to 11.3 mm in position 3.

In our study we found that the incidence of maximum diameter of the

Right IJV among the three positions was more common in position 1 (50%).

Hence placing the patient supine with head turned to left by 30 degree without

use of head pillow or shoulder results in maximum diameter of Right IJV. The

increase in diameter of the Right IJV in this position may help in improving first

pass success in cannulation as shown in previous studies.(15)

The overlap between the Right IJV and Carotid plays an important role in

inadvertent arterial puncture. It has been shown that neck rotation to less than 45

degree improves exposure with less overlap between internal jugular vein and

carotid as compared to greater degrees of rotation.(24–28) A study by

Lieberman et al reported that head rotation of 30 degree or less may reduce

chance of Carotid puncture in patients with high BMI and BSA whereas even 60

degrees of head rotation was suggested when BMI or BSA is low(24). In a study

77

by WK Chang et al there was a decrease in overlap between carotid and right

IJV from 55.3 +/- 25% to 28.7 +/- 28% when a 5 cm shoulder roll was used but

the anteroposterior diameter of right IJV decreased to 8.3 +/- 2.4 mm from 12.3

+/- 2.3 mm(32). In a study by Woo et al they found that overlap was more in

patients with high BMI based on head rotation than patients with low BMI for

the same degree of head rotation(25).

In our study the overlap was minimal when patients were placed in

position 3 (49%). But the diameter of the Right IJV was also reduced in this

position compared with the other positions. This may be due to compression of

the right IJV associated with neck extension which causes stretching of the neck

musculature. Hence use of larger shoulder rolls may cause more extension of the

neck which may lead to further compression of the right IJV. The findings are in

agreement with previous studies(32). Thus positioning with shoulder roll has the

advantage of reducing the overlap between Right Carotid and Right IJV but

results in a smaller Right IJV diameter.

. A study by Armstrong et al showed there was only a poor correlation

between IJV diameter and age, height and weight(17). There was no significant

change in diameter with age, height, weight and sex in the study by Dhulkhed et

al(23). We also compared the relationship of Right IJV diameter with height,

weight and BMI to see if there’s any significant correlation. Our study showed a

significant correlation between the weight (p value 0.0013 and correlation factor

0.308), BMI (p value 0.0009 and correlation factor 0.318) and antero-posterior

diameter of the Right IJV. There was an increase in Right IJV antero-posterior

diameter with increase in BMI.

78

There was no significant correlation between height, weight and BMI

with transverse diameter of the Right IJV or the percentage of Right Carotid

overlap with Right IJV. These findings were similar to the previous

studies(17,23)

79

LIMITATIONS

80

8. Limitations

One of the limitations of the study was using 100 percent as overlap for Carotid

located under the Right IJV. We could have measured the distance of the Carotid with

the medial border of Right IJV even when there was 100 percent overlap in various

positions to get better understanding of the relationship between both which might have

influenced the outcome of the study.

In our study the use of shoulder roll in obese patients was associated with

extreme extension of the head in some of them. A small sheet was used to support the

head in these patients. This may have led to minor changes in the measured values

when using shoulder roll in these patients.

81

CONCLUSION

82

9. Conclusion

The main findings from this study are

• The mean transverse diameter of the Right IJV was 18.7mm in

both position 1 and position 2 and 17.2 mm in position 3. Whereas

the mean anterposterior diameter was 13.9mm, 13.7mm and

11.3mm in positions 1,2 and 3 respectively.

• This difference was statistically significant. p < 0.0005

• Although the mean transverse diameter was the same in position 1

and 2, the incidence of maximum diameter among the 3 positions

was more common in position 1 (50%) than position 2 (36.79%).

• The mean overlap percentage between Right Carotid and Right

IJV was 49.41%, 50.97% and 35.7% in positions 1, 2 and 3

respectively.

• The difference in mean overlap percentage between position 3 and

other 2 positions was also statistically significant p<0.0005

The results of our study show that the diameter of the Right internal

jugular vein is the largest when no head pillow or shoulder roll is used in most of

the patients. It can be inferred that placing the patient in 15 degree

Trendelenberg tilt with no head pillow or shoulder roll with 30 degree head

rotation to the opposite side will lead to greater chance of first pass success

83

during right IJV cannulation as the diameter is largest in this position. We

suggest use of a head ring to stabilize the head.

Another significant finding in our study was that the overlap between the

Carotid and the Right IJV was least when shoulder roll was used to position the

patient. This position can be useful when there is significant overlap between

carotid and the right IJV to minimize the chance of carotid artery puncture. But

it should be kept in mind that the diameter of the Right IJV also is decreased in

this position.

84

REFERENCES

85

10. References

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2. Troianos CA, Jobes DR, Ellison N. Ultrasound-guided cannulation of the internal jugular vein. A prospective, randomized study. Anesth Analg. 1991 Jun;72(6):823–6.

3. Parienti J-J, Mongardon N, Mégarbane B, Mira J-P, Kalfon P, Gros A, et al. Intravascular Complications of Central Venous Catheterization by Insertion Site. N Engl J Med. 2015 Sep 24;373(13):1220–9.

4. Eisen LA, Narasimhan M, Berger JS, Mayo PH, Rosen MJ, Schneider RF. Mechanical complications of central venous catheters. J Intensive Care Med. 2006 Feb;21(1):40–6.

5. Lorente L, Henry C, Martín MM, Jiménez A, Mora ML. Central venous catheter-related infection in a prospective and observational study of 2,595 catheters. Crit Care Lond Engl. 2005;9(6):R631-635.

6. McGee DC, Gould MK. Preventing Complications of Central Venous Catheterization. N Engl J Med. 2003 Mar 20;348(12):1123–33.

7. Timsit J-F. What is the best site for central venous catheter insertion in critically ill patients? Crit Care. 2003;7(6):397–9.

8. Sulek CA, Blas ML, Lobato EB. A randomized study of left versus right internal jugular vein cannulation in adults. J Clin Anesth. 2000 Mar;12(2):142–5.

9. Anatomical Consideration in placement - jaet11i1p26.pdf [Internet]. [cited 2017 Aug 31]. Available from: http://medind.nic.in/jae/t11/i1/jaet11i1p26.pdf

10. Physical principles of ultrasound | Radiology Reference Article | Radiopaedia.org [Internet]. [cited 2017 Sep 4]. Available from: https://radiopaedia.org/articles/physical-principles-of-ultrasound-1

11. How Ultrasound Works [Internet]. [cited 2017 Sep 4]. Available from: https://www.physics.utoronto.ca/~jharlow/teaching/phy138_0708/lec04/ultrasoundx.htm

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12. Handbook of Critical Care and Emergency Ultrasound | AccessAnesthesiology | McGraw-Hill Medical [Internet]. [cited 2017 Sep 4]. Available from: http://accessanesthesiology.mhmedical.com/book.aspx?bookid=517

13. Ullman JI, Stoelting RK. Internal jugular vein location with the ultrasound Doppler blood flow detector. Anesth Analg. 1978 Feb;57(1):118.

14. Yonei A, Nonoue T, Sari A. Real-time ultrasonic guidance for percutaneous puncture of the internal jugular vein. Anesthesiology. 1986 Jun;64(6):830–1.

15. Gordon AC, Saliken JC, Johns D, Owen R, Gray RR. US-guided puncture of the internal jugular vein: complications and anatomic considerations. J Vasc Interv Radiol JVIR. 1998 Apr;9(2):333–8.

16. Bellazzini MA, Rankin PM, Gangnon RE, Bjoernsen LP. Ultrasound validation of maneuvers to increase internal jugular vein cross-sectional area and decrease compressibility. Am J Emerg Med. 2009 May 1;27(4):454–9.

17. Armstrong PJ, Sutherland R, Scott DHT. The effect of position and different manoeuvres on internal jugular vein diameter size. Acta Anaesthesiol Scand. 1994 Apr 1;38(3):229–31.

18. Kim HY, Choi JM, Lee Y-H, Lee S, Yoo H, Gwak M. Effects of the Trendelenburg Position and Positive End-Expiratory Pressure on the Internal Jugular Vein Cross-Sectional Area in Children With Simple Congenital Heart Defects: Medicine (Baltimore). 2016 May;95(18):e3525.

19. Kim JT, Kim HS, Lim YJ, Bahk JH, Lee KH, Kim CS, et al. The influence of passive leg elevation on the cross-sectional area of the internal jugular vein and the subclavian vein in awake adults. Anaesth Intensive Care. 2008 Jan;36(1):65–8.

20. Marcus HE, Bonkat E, Dagtekin O, Schier R, Petzke F, Wippermann J, et al. The impact of Trendelenburg position and positive end-expiratory pressure on the internal jugular cross-sectional area. Anesth Analg. 2010 Aug;111(2):432–6.

21. Clenaghan S, McLaughlin R, Martyn C, McGovern S, Bowra J. Relationship between Trendelenburg tilt and internal jugular vein diameter. Emerg Med J EMJ. 2005 Dec;22(12):867–8.

22. Parry G. Trendelenburg position, head elevation and a midline position optimize right internal jugular vein diameter. Can J Anaesth J Can Anesth. 2004 Apr;51(4):379–81.

23. Dhulkhed VK, Reddy A, Gupta AK, Dhulkhed P. An Observational Study Of Change In Diameter Of Right Internal Jugular Vein With Various Body Positions In Volunteers With The Aid Of 2-Dimensional Ultrasonography. Internet J Anesthesiol [Internet]. 2008 Dec 31 [cited 2017 Jul 21];21(2). Available from: http://ispub.com/IJA/21/2/11524

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24. Lieberman JA, Williams KA, Rosenberg AL. Optimal head rotation for internal jugular vein cannulation when relying on external landmarks. Anesth Analg. 2004 Oct;99(4):982–988, table of contents.

25. Woo JH, Kim Y, Kim DY, Baik HJ, Kim JH, Han JI. Is Head Rotation Preferred During Right Internal Jugular Vein Cannulation in Obese Asians? J Anesth Clin Res [Internet]. 2012 Oct 14 [cited 2017 Jul 21]; Available from: https://www.omicsonline.org/is-head-rotation-preferred-during-right-internal-jugular-vein-cannulation-in-obese-asians-2155-6148.1000245.php?aid=9757

26. Wang R, Snoey ER, Clements RC, Hern HG, Price D. Effect of head rotation on vascular anatomy of the neck: an ultrasound study. J Emerg Med. 2006 Oct;31(3):283–6.

27. Sulek CA, Gravenstein N, Blackshear RH, Weiss L. Head rotation during internal jugular vein cannulation and the risk of carotid artery puncture. Anesth Analg. 1996 Jan;82(1):125–8.

28. Guidance on the use of ultrasound locating devices for placing central venous catheters | Guidance and guidelines | NICE [Internet]. [cited 2017 Sep 7]. Available from: https://www.nice.org.uk/guidance/ta49

29. Denys BG, Uretsky BF, Reddy PS. Ultrasound-assisted cannulation of the internal jugular vein. A prospective comparison to the external landmark-guided technique. Circulation. 1993 May;87(5):1557–62.

30. Slama M, Novara A, Safavian A, Ossart M, Safar M, Fagon JY. Improvement of internal jugular vein cannulation using an ultrasound-guided technique. Intensive Care Med. 1997 Aug;23(8):916–9.

31. Brass P, Hellmich M, Kolodziej L, Schick G, Smith AF. Ultrasound guidance versus anatomical landmarks for internal jugular vein catheterization. Cochrane Database Syst Rev. 2015 Jan 9;1:CD006962.

32. Chang W-K, Wang Y-C, Ting C-K, Cheng H-W, Chan K-H, Chen P-T. Optimal shoulder roll height for internal jugular venous cannulation: a study of awake adult volunteers. J Clin Anesth. 2012 May;24(3):179–84.

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11. Annexures

IRB approval letter:

89

90

91

92

Consent form and Patient Information Sheet

Patient Information Sheet Department of Anaesthesia, Christian Medical College and Hospital

A study on effect of head pillow, shoulder roll and head rotation on Right IJV caliber in patients undergoing elective surgery under general anaesthesia

What is this study about?

We are inviting you to be part of our study on finding the optimal position for Right internal jugular vein(RIJV) cannulation. The right internal jugular vein is a blood vessel which is commonly used by anaesthetist to administer various drugs and to monitor patients during surgery. It is associated with various complications. We are conducting this study to find optimal position which will improve success rate and reduce complications associated with the procedure.

How will this study be done?

Upon your willingness to participate in this study, you will be anaesthetised according to standard protocol. The principal investigator (or one of the co-investigator) will use ultrasound to measure the right internal jugular vein diameter, carotid artery diameter and RIJV overlap with Carotid artery first in supine position on the operating table. Then measurements will be repeated with head pillow,shoulder roll and your head turned towards the left side by 30 degree. Your course in the hospital and the care you receive during the surgery and postoperative care unit will be the same, whether or not you are part of this study.

What are the benefits of participating in this study?

There will be no immediate benefits to you but your participation will help in improving success rate and reducing complications associated with right internal jugular vein cannulation. If you require central line cannulation in the future this study will benefit you.

Will there be any risk in participating in this study?

This study is done using ultrasound which has been proven to be safe and there is no risk of radiation as it uses sound waves to visualize your vein and artery. No needle will be inserted during the study.

Will there be any additional cost for the study ?

93

There will be no additional cost for participating in the study.

Will my personal information be shared with anyone?

The results of this study will be published in a medical journal but you will not be identified by name in any publication or presentation of results. However, your medical notes may be reviewed by people associated with the study, without your additional permission, should you decide to participate in this study.

Will my treatment be affected if I am not participating in this study?

Whether you accept or decline to be a part of this study, your further treatment at this hospital will not be affected. All details collected will be kept confidential and will be accessible only to those on the study team. Participation in this study is purely voluntary, and you can withdraw from the study at any time and that refusal to participate will not involve any penalty or loss of benefits to which you are otherwise entitled.

94

Consent form

Department of Anaesthesia Christian Medical College, Vellore

A study on effect of head pillow, shoulder roll and head rotation on Right IJV caliber in patients undergoing elective surgery under general anaesthesia

Study Number: ____________

Subject’s Name: _________________________________________

Date of Birth / Age: __________________________

(i) I confirm that I have read and understood the information sheet dated ____________ for the above study and have had the opportunity to ask questions. [ ]

(ii) I understand that my participation in the study is voluntary and that I am free to withdraw at any time, without giving any reason, without my medical care or legal rights being affected. [ ]

(iii) I understand that the Sponsor of the clinical trial, others working on the Sponsor’s behalf, the Ethics Committee and the regulatory authorities will not need my permission to look at my health records both in respect of the current study and any further research that may be conducted in relation to it, even if I withdraw from the trial. I agree to this access. However, I understand that my identity will not be revealed in any information released to third parties or published. [ ]

(iv) I agree not to restrict the use of any data or results that arise from this study provided such a use is only for scientific purpose(s). [ ]

(v) I agree to take part in the above study. [ ]

Signature (or Thumb impression) of the Subject/Legally Acceptable

Date: _____/_____/______

Signatory’s Name: _________________________________ Signature:

Or Thumb Impression:

95

Signature of the Investigator: ________________________

Date: _____/_____/______

Study Investigator’s Name: _________________________

Signature or thumb impression of the Witness: ___________________________

Date: _____/_____/_______

Name of the witness:

96

Data collection form:

Data collection sheet

Study Title

A study on effect of head pillow, shoulder roll and head rotation on Right IJV caliber in patients undergoing elective surgery under general anaesthesia.

Serial no:

Hospital No: Age: Sex:

Height: Weight: BMI:

ASA Class:

Measurements Supine With Head pillow With shoulder roll

Right IJV diameter

Transverse

Anteroposterior

Right Carotid diameter

Right IJV carotid overlap

Percentage of overlap *

*Percentage of overlap

RIJV overlap of Carotid x 100 Carotid artery diameter

Date:

Name of the investigator:

Sign:

97

Data sheet:

sno age sex ht wt bmi asa ijvt ijvap ct o op ijvht ijvhap cth oh oph ijvs t ijvsap cts os ops1 62 1 168 62 22 2 1.68 1.1 0.65 0.65 100 1.91 1.37 0.63 0.63 100 1.68 1.26 0.63 0.63 1002 42 1 164 65 24.2 1 1.92 1.7 0.65 0.5 76.92 2.01 1.69 0.71 0.46 64.78 1.56 0.85 0.65 0.15 23.073 45 1 164 75 27.9 2 1.6 1.09 0.65 0 0 1.47 1.13 0.61 0 0 1.53 0.86 0.69 0.19 27.534 61 2 148 26 11.9 2 1.44 1.07 0.76 0.47 61.84 1.66 1.23 0.75 0.46 61.33 1.48 0.99 0.68 0.33 48.525 50 1 162 70 26.7 1 1.51 1.23 0.68 0.34 50 1.65 1.15 0.63 0.43 68.25 1.43 0.99 0.64 0.36 56.256 47 2 153 70 29.9 2 2.03 2.03 0.64 0.33 51.56 2.32 2.11 0.61 0.43 70.49 1.91 1.78 0.67 0.19 28.357 47 1 162 73 27.8 2 1.81 1.55 0.68 0 0 1.67 1.36 0.63 0 0 1.77 1.22 0.62 0 08 64 1 157 66 26.8 2 2.45 1.73 0.79 0.79 100 2.47 1.9 0.65 0.65 100 2.25 1.61 0.71 0.37 52.119 40 1 164 62 23.6 2 1.75 1.44 0.65 0.32 49.23 1.62 1.05 0.69 0.39 56.52 1.77 1.42 0.73 0.33 45.210 42 2 154 35 14.8 2 1.63 1.43 0.62 0.31 50 1.4 0.98 0.63 0.11 17.46 1.5 1.37 0.59 0.25 42.3711 41 1 168 67 23.7 2 1.6 1.29 0.66 0.36 54.54 1.54 1.35 0.65 0.44 67.69 1.4 0.94 0.63 0.3 47.6112 46 1 165 75 27.5 2 1.85 1.2 0.59 0.28 47.45 1.93 1.57 0.56 0 0 1.57 1.19 0.59 0.1 16.9413 38 1 171 56 19.2 1 1.81 1.26 0.64 0.41 64.06 1.92 1.36 0.7 0.43 61.42 1.5 0.73 0.7 0.43 61.4214 46 2 163 67 25.2 2 1.17 1.07 0.67 0.11 16.41 1.18 1.07 0.67 0 0 1.31 0.94 0.59 0 015 50 2 153 59 25.2 1 2.24 1.57 0.59 0.56 94.91 2.14 1.57 0.52 0.51 98.07 2.17 1.3 0.67 0.6 89.5516 19 2 156 37 15.2 1 1.63 1.15 0.68 0.53 77.94 1.58 1.09 0.59 0.39 66.1 1.35 0.81 0.58 0.33 56.8917 60 1 158 58 23.2 2 2.19 1.55 0.87 0.62 71.26 1.81 1.47 0.77 0.17 22.07 1.72 1.04 0.74 0.04 5.418 63 1 165 63 23.1 2 1.74 1.23 0.85 0.26 30.58 1.71 1.13 0.86 0.19 22.09 1.67 1.03 0.85 0.07 8.2319 21 1 168 51 18.1 1 1.83 1.6 0.67 0.3 44.77 1.71 1.49 0.63 0.25 39.68 1.78 1.32 0.75 0.21 2820 48 1 164 59 21.9 2 1.81 1.55 0.65 0.29 44.61 1.87 1.65 0.71 0.23 32.39 1.75 1.55 0.72 0.25 34.7221 76 2 153 46 19.7 2 2.81 1.79 0.66 0.66 100 2.99 1.75 0.67 0.67 100 2.06 1.19 0.61 0.31 50.8122 58 1 171 51 17.4 1 2.54 1.64 0.75 0.75 100 2.6 1.63 0.69 0.69 100 2.82 1.67 0.91 0.91 10023 47 1 163 53 19.9 1 1.49 1.21 0.67 0.26 38.8 1.48 1.26 0.61 0.23 37.7 1.37 0.93 0.61 0.12 19.6724 45 1 165 62 22.8 2 1.76 1.21 0.49 0 0 1.77 1.21 0.56 0 0 1.43 0.7 0.54 0 025 38 2 144 35 16.9 2 1.79 1.33 0.63 0.14 22.22 2.1 1.4 0.7 0.25 35.71 1.82 0.87 0.57 0.15 26.3126 32 1 175 87 28.4 1 2.16 1.56 0.63 0.16 25.39 2.29 1.68 0.65 0.21 32.3 1.93 1.3 0.58 0 027 37 2 159 63 24.9 1 1.51 1.34 0.65 0.17 26.15 1.3 1.13 0.81 0.4 49.38 1.38 1.23 0.7 0.38 54.2828 64 2 143 45 22 2 1.21 0.71 0.71 0 0 1.22 0.69 0.75 0.14 18.66 1.15 0.68 0.63 0 029 53 1 165 64 23.5 2 1.95 1.46 0.68 0.41 60.29 1.95 1.46 0.71 0.23 32.39 1.75 1.27 0.75 0.27 3630 46 1 175 75 24.5 2 1.85 1.72 0.59 0 0 1.95 1.71 0.6 0 0 1.67 1.02 0.61 0 031 24 1 164 58 21.6 2 1.18 1.1 0.52 0 0 1.03 1.2 0.61 0 0 0.86 0.55 0.61 0 032 43 2 157 45 18.3 1 1.2 0.97 0.48 0 0 1.19 0.95 0.5 0 0 0.94 0.58 0.5 0 033 59 1 164 69 25.7 2 2.12 1.52 0.59 0.59 100 2.33 1.47 0.68 0.68 100 1.86 1.12 0.8 0.45 56.2534 31 2 160 55 21.5 1 2.34 1.23 0.82 0.15 18.29 2.5 1.4 0.93 0.18 19.23 2.31 0.78 0.8 0 035 39 2 163 68 25.6 1 1.32 1.12 0.71 0.14 19.71 1.36 1.1 0.6 0.19 31.66 1.4 1.04 0.67 0.17 25.3736 40 2 160 65 25.4 1 1.5 1.32 0.57 0.43 75.43 1.45 1.11 0.54 0.45 83.33 1.17 0.83 0.57 0.17 29.8237 38 1 160 60 23.4 2 1.89 1.68 0.74 0.46 62.16 1.89 1.53 0.7 0.55 78.57 1.76 1.35 0.69 0.38 55.0738 44 2 158 51 20.4 1 1.64 1.47 0.63 0.07 17.94 2.22 1.62 0.56 0.39 69.64 2.3 0.94 0.63 0 039 33 2 160 50 19.5 1 2.04 1.51 0.6 0 0 1.92 1.65 0.6 0 0 1.75 1.04 0.7 0.05 7.1440 57 2 150 65 28.9 2 1.36 1.23 0.57 0 0 1.68 1.24 0.56 0.1 17.85 1.52 1.22 0.54 0 041 61 1 165 65 23.5 2 1.42 1.15 0.97 0.17 17.52 1.55 1.17 1.05 0.23 21.9 1.27 0.89 0.95 0 042 32 1 165 44 16.3 1 1.87 1.25 0.53 0.38 71.69 1.54 0.94 0.58 0.25 43.1 1.38 0.8 0.6 0.35 58.3343 39 2 152 53 22.6 1 1.58 1.29 0.61 0.17 27.86 1.53 1.34 0.64 0.18 28.12 1.41 1.17 0.61 0 044 44 1 165 51 18.7 2 2.52 1.51 0.6 0.27 45 2.42 1.46 0.72 0.29 40.27 2.02 0.72 0.52 0.16 30.7645 50 1 167 65 23.3 1 2.48 1.33 0.62 0.6 100 2.23 1.4 0.67 0.67 100 2.4 1.08 0.65 0.65 10046 66 1 155 55 22.9 2 2.14 1.43 0.68 0.53 77.94 2.09 1.4 0.68 0.55 80.88 1.91 1.36 0.63 0.59 93.6547 33 2 155 65 27.1 1 1.82 1.56 0.55 0.16 29.09 1.77 1.52 0.49 0.07 14.28 1.74 1.46 0.54 0.16 29.6248 36 2 154 76 32 1 1.69 1.23 0.6 0.34 56.66 1.6 1.14 0.59 0.3 50.84 1.56 1.12 0.72 0.35 48.6149 26 1 166 82 29.8 1 1.33 1.16 0.5 0 0 1.28 0.93 0.54 0 0 1.29 1.03 0.58 0 050 43 1 179 73 22.8 1 1.66 1.12 0.63 0.07 11.11 1.52 1.16 0.64 0 0 1.32 0.67 0.54 0 051 35 1 167 79 28.3 1 1.67 1.43 0.53 0.53 100 1.82 1.5 0.46 0.46 100 1.47 1.21 0.48 0.48 10052 35 2 154 83 35.2 2 2.34 1.97 0.61 0.61 100 2.3 1.78 0.62 0.62 100 2.1 1.57 0.65 0.65 10053 48 1 166 51 18.5 1 1.6 1.12 0.7 0.23 32.85 1.38 0.93 0.74 0.23 31.08 1.49 0.67 0.62 0.18 29.0354 46 2 153 67 28.6 2 1.38 1.1 0.64 0 0 1.4 1.12 0.68 0 0 1.48 0.98 0.63 0 055 61 1 162 54 20.6 2 1.76 1.23 0.5 0.45 90 1.68 1.3 0.52 0.39 75 1.41 1.03 0.58 0.36 62.0656 38 2 153 59 25.2 1 2.05 1.5 0.68 0.31 45.58 2.02 1.17 0.75 0.42 56 1.84 1.15 0.76 0.31 40.7857 41 2 154 59 24.9 2 1.85 1.47 0.63 0.25 39.68 1.87 1.38 0.73 0.54 73.97 1.78 1.34 0.6 0.38 63.3358 51 1 166 62 22.7 1 1.98 1.39 0.56 0.41 73.21 1.87 1.28 0.6 0.47 78.33 1.53 1.03 0.7 0.18 25.7159 56 2 144 55 26.5 2 1.98 1.43 0.55 0.55 100 1.93 1.25 0.5 0.5 100 1.8 1.3 0.65 0.27 41.5360 69 2 151 71 31.3 2 2.24 1.66 0.59 0.59 100 2.07 1.65 0.58 0.58 100 2.06 1.59 0.78 0.64 82.0561 50 2 159 70 27.7 2 2.21 1.41 0.64 0.47 73.43 2.09 1.35 0.6 0.3 50 2.03 1.51 0.56 0.37 66.0762 46 1 167 84 30.1 2 2.94 2.24 0.63 0.63 100 2.46 1.79 0.81 0.12 14.81 2.72 1.98 0.7 0.45 64.2863 58 1 155 69 28.7 2 3.14 2.1 0.86 0.86 100 2.58 1.94 0.97 0.68 70.1 2.89 1.94 1.05 0.64 60.9564 55 1 169 64 22.4 2 1.76 1.16 0.73 0.19 26.02 1.66 1.28 0.68 0.22 32.35 1.78 1.51 0.77 0.41 53.2465 64 2 145 60 28.5 2 1.67 1.55 0.76 0.12 75 1.81 1.68 0.67 0 0 1.55 1.55 0.89 0 066 51 1 151 62 27.2 2 2.3 1.75 0.61 0.46 75.4 2.36 1.92 0.65 0.38 58.46 2.08 1.46 0.57 0.25 43.8567 49 2 157 78 31.6 2 1.94 1.32 0.57 0.29 50.87 1.96 1.43 0.57 0.38 66.66 1.87 1.41 0.57 0.3 52.6368 51 1 164 61 22.7 1 1.52 1.21 0.67 0.23 34.32 1.37 1.11 0.68 0.42 61.76 1.18 0.99 0.67 0.12 17.9169 19 1 175 51 16.7 1 1.57 1.11 0.77 0 0 1.66 1.19 0.69 0 0 1.32 0.55 0.78 0 070 41 1 175 55 18 2 2.45 1.16 0.64 0.16 25 2.37 1.46 0.68 0.45 66.17 1.93 0.57 0.77 0 071 41 2 154 64 27 2 2.04 1.28 0.6 0.56 93.33 2.45 1.36 0.63 0.39 61.9 1.98 0.9 0.72 0.2 27.7772 42 2 148 65 29.7 2 1.72 1.4 0.6 0.56 93.33 1.78 1.33 0.63 0.63 100 1.42 0.96 0.5 0.15 3073 40 1 175 69 22.5 2 1.87 1.23 0.8 0.12 15 2.25 1.37 0.79 0.17 21.51 1.72 0.91 0.8 0 074 61 1 165 65 23.9 2 2.38 1.68 0.61 0.54 88.52 2.48 1.77 0.62 0.62 100 2.22 1.11 0.66 0.47 71.2175 45 2 155 69 28.7 2 2.34 1.56 0.6 0.6 100 2.33 1.63 0.57 0.57 100 2.23 1.39 0.66 0.39 59.0976 48 2 154 51 21.5 2 2.03 1.38 0.69 0.26 37.68 1.78 1.23 0.67 0.42 62.68 1.62 0.96 0.67 0.13 19.477 21 2 169 59 20.7 1 1.19 0.85 0.58 0 0 1.05 0.86 0.52 0 0 0.95 0.5 0.44 0.08 18.1878 58 1 164 68 25.5 2 2.28 1.45 0.71 0.28 39.43 2.2 1.4 0.73 0.33 45.2 2.09 1.16 0.71 0.17 23.9479 53 2 148 85 38.8 2 1.67 1.37 0.61 0.32 52.45 1.67 1.42 0.6 0.36 60 1.55 1.19 0.58 0.32 55.1780 55 1 175 78 25.5 2 2.42 1.77 0.53 0.53 100 2.74 1.76 0.58 0.58 100 2.43 1.67 0.57 0.23 40.3581 63 1 170 76 26.3 2 2 1.5 0.82 0.53 64.63 1.93 1.37 0.95 0.35 36.84 1.98 1.42 0.79 0.65 82.2782 72 2 147 45 20.8 2 2.03 1.38 0.62 0.58 93.54 1.99 1.44 0.63 0.6 95.23 1.87 1.37 0.54 0.5 92.5983 58 2 160 72 28.1 2 2.15 1.89 0.83 0 0 1.89 1.45 0.65 0.26 40 2.08 1.42 0.86 0 084 50 2 152 60 26 1 2.04 1.09 0.75 0.13 17.33 1.96 1.15 0.78 0.69 88.46 1.71 0.77 0.69 0.08 11.5985 67 1 171 66 22.6 2 2.22 1.76 0.6 0.6 100 2.31 1.51 0.63 0.63 100 1.96 1.14 0.82 0.54 65.8586 47 1 158 60 24 2 2.17 1.48 0.46 0.46 100 1.88 1.68 0.46 0.46 100 2.03 1.42 0.48 0.48 10087 50 2 146 38 17.8 1 1.84 1.07 0.76 0.28 36.84 1.92 1.16 0.79 0.36 45.56 1.87 0.76 0.73 0.12 16.4388 39 2 157 75 30.4 2 1.27 1.26 0.67 0 0 1.35 1.3 0.59 0 0 1.3 1.33 0.62 0.07 11.2989 45 1 168 50 17.7 1 1.7 1.08 0.5 0.3 68 2.31 1.31 0.58 0.27 46.55 2.02 1.28 0.43 0 090 27 2 150 60 26.7 1 1.6 1.34 0.67 0.07 10.44 1.53 1.38 0.48 0.33 68.75 1.9 1.33 0.59 0.39 66.191 35 1 168 60 21.3 1 1.88 1.34 0.67 0.45 67.16 1.35 0.92 0.64 0.64 100 1.39 1.14 0.64 0.14 21.8792 36 1 165 77 28.3 2 1.7 1.49 0.57 0.57 100 1.57 1.35 0.61 0.44 72.13 1.11 1.07 0.63 0.1 15.8793 37 2 166 69 27 1 1.52 0.94 0.64 0.23 35.93 1.93 1.28 0.5 0.5 100 1.34 0.57 0.58 0 094 29 1 166 70 25.4 2 1.57 1.25 0.51 0 0 1.54 1.26 0.55 0.08 14.54 1.7 0.98 0.4 0 095 43 1 167 75 26.9 2 2.23 1.48 0.81 0.16 19.75 2.06 1.43 0.64 0 0 2.09 1.33 0.61 0 096 39 2 158 60 24 1 1.73 1.29 0.58 0.21 36.2 1.95 1.43 0.6 0.39 65 1.4 0.84 0.63 0 097 33 2 164 61 22.7 1 2.14 1.76 0.66 0.53 80.3 2.07 1.67 0.67 0.3 44.77 1.93 1.49 0.65 0.36 55.3898 24 2 160 60 23.4 2 1.43 1.31 0.64 0.14 21.87 1.35 1.25 0.61 0.12 19.67 1.3 1.09 0.55 0.05 9.0999 37 1 175 80 26.1 1 2.02 1.51 0.62 0.3 48.38 2 1.62 0.57 0.24 42.1 1.91 1.41 0.6 0.19 31.66100 30 2 158 75 30 2 1.43 1.09 0.54 0.54 100 1.18 0.77 0.6 0.28 46.66 1.38 0.76 0.57 0.18 31.57101 60 1 162 96 36.6 2 2.21 1.79 0.62 0.62 100 2.28 1.9 0.57 0.57 100 2.29 1.76 0.6 0.6 100102 33 2 157 67 27.2 1 1.76 1.4 0.64 0.05 7.81 1.97 1.22 0.61 0.07 11.41 1.69 0.86 0.57 0.26 45.61103 67 1 165 66 24.2 2 1.55 1.25 0.75 0.26 34.66 1.78 1.22 0.7 0.24 34.28 1.71 1.12 0.66 0.22 33.33104 67 2 155 68 28.3 2 1.42 0.95 0.46 0.46 100 1.52 1.02 0.47 0.47 100 1.04 0.76 0.41 0.41 100105 42 1 157 76 30.8 2 2.18 1.53 0.87 0.25 28.7 2.26 1.45 0.78 0.38 48.7 2.35 1.26 0.84 0.43 51.11106 64 2 150 56 24.9 2 2.47 1.55 0.57 0.09 15.78 2.4 1.44 0.6 0.37 61.66 2.24 1.25 0.6 0 0

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