Airway management in stimulated cervical trauma scenarios

Airway management :Comparative study between

McGrath VL , Airtraq VL

and

Macintosh laryngoscope

in neutral neck position

Presented by

Alaa Elsayed Goma FalogyM.Sc. of Anaesthesia and surgical intensive care

Faculty of medicine

Zagazig university

2016

Under supervision of

Professor

Ayman Abdel El-Salam

Professor of Anesthesia and surgical

Intensive Care

Faculty of Medicine – Zagazig university


Professor

Ahmed Abd El-Hakim Balata


Intensive Care



Professor

Khaled Mohammed El-Sayed


Intensive Care


Prof. Dr.

Ayman Abdel SalamMy deep gratitude and greatest debt

for his sincere guidance.

Thanks My Dear prof; Ayman

Prof. Dr.

Ahmed Abdel Hakim Balata,

for his kind supervision, valuable

guidance and for being always backing

and supporting.

Thanks Dear Dr, Ahmed

Prof. Dr.

Khaled Mohammed ElsayedReal kindness and deepest support

Thanks Dear Dr, Khaled .

Disclosure & Conflict of interestThe researcher confirm and

stated that:

the manufacturers of the

neither Airtraq nor McGrath

VL, had NO involvement in

the;

concept,

design ,

conduct,

analysis, or

write-up of this clinical trial

Research questionIf……

used by [experienced anesthiologists]

managing a model of a difficult airway in

form of neck immobilization by semi- rigid

neck collar

Do………

[the Airtraq and the McGrath VL]

Are……

[more safe and more effective in tracheal

intubation ] when compared with [Classic

Macintosh laryngoscope]?

Introduction

INTRODUCTION:• Airway management is a major challenge upon

the anaesthesiologists in their everyday

operative practice.

• During direct laryngoscopy, positioning of the

head and neck in

NEUTRAL POSITION

will decrease chance of optimal laryngeal

visualization which derange the line of sight

between laryngeal , pharyngeal and oral axes.

INTRODUCTION:

• patients with cervical spine instability, airway

management implies upon a high risk of

neurological damage related to head and neck

manipulation, so semi-rigid neck collar is applied

in trail to control neck movement during tracheal

intubation.

• Such immobilisation technique can turn

intubation under the direct laryngoscopy into

more difficult situation (corrupted line of sight) .

INTRODUCTION:

• These concerns have aroused the idea to developnumber of alternatives to classical Macintoshlaryngoscope such as Airtraq ®, McGrath® Videolaryngoscope.

• These laryngoscopes do not require the arrangement ofpharyngeal, laryngeal and oral axis in one line of sightand thus do not require modulation of neutral headposition.

• During difficult airway situations, both Airtraq opticallaryngoscope and McGrath Video laryngoscope soundto be better than Macintosh laryngoscope

AIM OF THE WORK• To evaluate the efficacy and safety of :• Airtraq Laryngoscope and

McGrath Video Laryngoscope versusClassical Macintosh Laryngoscope

• in stimulated difficult intubation situations• in patients with their cervical spine kept in

neutral position• by semi-rigid neck collar as an

immobilization techniques.

in stimulated difficult intubation situations

in patients with their cervical spine kept in neutral position

by semi-rigid neck collar as an immobilization techniques.

Concept of line of sight

during direct laryngoscopy :

Idea of Alignment of 3 axes in direct

laryngoscopy

Situation

Stimulated difficult intubation

Patients with their cervical spine kept in neutral neck position

Semi-rigid neck collar

Cervical spine stability:

Cervical Stability:

is the ability of the

spine to maintain

relationships

between vertebrae,

so as not to

damage the neural

structures contained

within the spinal

column

Cervical instability:

Is defined as over

translational or

rotational motion of

any vertebra and

means that the

odontoid process is

no longer firmly

held against the

back of the anterior

arch of C1.

Cervical spine

immobilization: Cervical immobilization

during laryngoscopy appliesequal force in oppositedirection to that generatedby the laryngoscopist.

To keep head and neck inneutral position, anassistant grasps themastoid process withfingertips while the palm ofthe hand cradles theocciput.

Concept of

Videolaryngoscopy: Video laryngoscopy (VL) is an

update of high resolution

micro-cameras systems that

improves the success rate of

intubation.

There is hypothesis improved

lighting and a better view can

increase the intubation

success.

Anaesthesia had used the

miniature camera for many

years but for only bronchial

endoscopy .

Video Laryngoscopy in difficult

Airway management :

Video Laryngoscopy in difficult

Airway management :

Video Laryngoscopy in difficult Airway

management (after unsuccessful attempts) :

McGrath video-laryngoscope

The McGrath Video Laryngoscope:

(Aircraft Medical, Edinburgh, United Kingdom)• a video-based system for tracheal intubation thatutilizes a video camera embedded into a camerastick.

• The unit is powered by a single easily-replaceable1.5 v AA battery

• features a single electronic control; an on/offswitch located on the top of the unit.

• It therefore offers the user an image of the vocalcords and the surrounding airway anatomy on aliquid crystal display (LCD) screen.

McGrath Video Laryngoscope:

• The unit which is used as a part of much thesame way as common as Macintoshlaryngoscope

• with a special case that once it has beenbrought into mouth by a couple centimeters,operator’s attention must be directed to theLCD show.

• In video laryngoscopes we pay attention onthe superior view and access provided byvideo screen show

The McGrath Video Laryngoscope:

• The intubationist uses direct vision to insertthe video laryngoscope in the mouth andthen the video-imaging screen to obtain thebest possible perspective view of the glottis(step 2).

• In step 3, the eyes then returned to theoropharynx to introduce the ETT and thenback to the video image screen toaccomplish the intubation (step 4).

Concept of the improved

glottic view

AIRTRAQ Optical Laryngoscope

AIRTRAQ Optical Laryngoscope

based on refraction prism principle to give an angular

view of the glottic area.

The blade of the Airtraq consists of two side by side

channels.

One channel act as housing for the ETT, and the other

channel terminates in terminal lenses and transmit back

the image.

The viewed image is then been transmitted to a proximal

eye piece viewfinder employing a prisms system and lenses

not as basic concepts of usual fiberoptics.

The “View” Optics and guiding channel “point” the user to the

center of the viewing window.

The user only has to center the vocal cords in the

middle of the image and the ETT goes in.

Glottis

Viewer

ETTOptics

Macintosh

laryngoscope

PATIENTS AND METHODS

METHODOLOGY

This was a prospective, randomized clinical trial.

group assignments (C, A and M)

age group of 20-50 years, ASAps Grades I or II

undergoing elective surgery requiring general

Anaesthesia

three groups of 50 patients each.

Inclusion criteria

Of either sex

Within the age group of 20-50 years,

ASAps Grades I or II

Undergoing elective surgery

Requiring general Anaesthesia and endotracheal

intubation

Exclusion criteria

Include:

Anticipated Difficult Airway (Mallampati Class III

And IV)

Thyromental Distance <6 Cm)

BMI>35

Cardiovascular Disease

Endocrine Disease,

Presence Of Risk Factors For Gastric Aspiration

E.G. Pregnancy, Diabetes, Etc.

Standard monitoring

All patients received standard monitoring included

electrocardiography,

non-invasive arterial blood pressure,

pulse oximeter,

end-tidal carbon-dioxide.

Heart rate (HR), mean arterial blood pressure (MAP)

and Oxygen saturation were recorded pre and post-

intubation.

INTUBATION PROCEDURE

Pre-oxygenation

Induction of anesthesia, administration of

fentanyl 1.5μg/kg (i.v.) then propofol 2 mg/kg

followed by rocuronium bromide 1 mg/kg.

Then neck was immobilized using semi-rigid

neck collar of appropriate size (Zola Collar, Egypt)

and was kept in place throughout airway

management process.


Tracheal intubation was then undertaken using

one of the study devices.

Intubation was performed by an experienced

anesthesiologist with accepted experience in two

recent video laryngoscopes under study.

A malleable stylet was used in both groups

(Classical Macintosh and McGrath VL).


The technique was considered failed if tracheal

intubation was not achieved within 120 seconds

or

within a maximum of three intubation attempts.

Mucosal damage was defined as the presence of

blood on the devices following intubation

process.


The glottic view was assessed and recorded

using Cormack and Lehane grading (C&L grade)

system.

CORMACK & LEHANE SCORE

Grade I Grade II

Grade III Grade IV


Intubation time was separated into T1 and T2.

T1 is the time between insertions of the allocated

laryngoscope in the mouth until optimal glottic view

including optimization maneuvers.

T2 is the time from optimal glottic view till

confirmation of tracheal intubation (by vision)

including removal of the device.

Intubation sequence by McGrath VL

With the patient in neutral position, Use left hand to

introduce the VL into the midline of the oropharynx.

Push the blade tip till the tip is past the posterior portion

of the tongue.

Now, move eyes to the video screen in order to

manipulate the video scope and obtain the best view of the

glottis.

Advance and withdraw the laryngoscope slightly while

changing the tilt of the blade along with the camera and

seat the device in the vallecula


The video image of the glottis now is

representing Cormack – Lehane view.

The styletted ETT is then inserted under direct

vision. Using video visualization, the ETT is

then advanced on a smooth curve through the

glottis.





55


56

Intubation sequence by Airtraq OL

Add lubricant to outer surface of the

endotracheal tube.

Embed the tube into the side holding channel of

the Airtraq so that the tip of the endotracheal

tube is at the tip margin of the side channel.

Turn on the light for about 30-60 seconds

before the procedure.

57


Hold the device in the mouth in the midline.

advance by sliding the device over the tongue.

check the image on view finder to optimize the

view by moving the blade right and left as

necessary.

Be sure that the laryngeal inlet is in the centre of

viewfinder just before pushing forward the

ETT.

58







RESULTS

OF

THE

STUDY

Comparison between groups are done

according to:

INTUBATION CONDITIONS

NUMBERS OF ATTEMPTS

Optimization Procedures

Cormack and Lehane score

IDS

SUCCESS RATE OF INTUBATION

TIME TO INTUBATION

HEMODYNAMICS

COMPLICATIONS

DEMOGRAPHIC DATA

NO significant differences in demographic data

regarding

Age,

Gender,

Height,

Weight,

Body mass index and

ASAps among the studied groups

DEMOGRAPHIC DATA

68

Demographic data Group C Group A Group M p-value (Sig.)

(N=50) (N=50) (N=50)

Age (in years) 35.90±7.65 35.92±7.70 35.16±7.72 0.856** (NS)

Male / Female 62 / 38 % 66 / 34 % 60 / 40 % 0.892* (NS)

Height (cm) 171.48±3.71 171.62±3.54 171.6±3.8 0.981** (NS)

Weight (Kg) 77.96±7.22 77.62±6.25 76.86±6.93 0.619** (NS)

BMI (Kg/m2) 26.84±2.29 27.06±2.05 26.14±2.13 0.095** (NS)

ASAps I / II 14 / 86 % 16 / 84 % 10/ 90 % 0.668* (NS)

MS I / II 56 / 44 % 48 / 52 % 62 / 38 % 0.369* (NS)

TMD (cm) 7.18±0.34 7.12±0.34 7.17±0.32 0.766** (NS)

DEMOGRAPHIC DATA

INTUBATION PROCESS

PARAMETERS

Parameters p-value (Sig.)

Numbers of attempts (<0.001)*(HS)

1st

/2nd

/3rd

(0.002)* (HS)

Optimization: No/YES (<0.001)* (HS)

ID score (<0.001)**(HS)

Successfulness (0.068)* (NS) C&L I/ II / III <0.001)*(HS))

Complications: No / YES (0.135)* (NS)

INTUBATION PROCESS

PARAMETERS SUMMARY

Numbers of attempts

Videolaryngoscope WINS

HS

INTUBATION PROCESS

PARAMETERS SUMMARY

OPTIMIZATION

Videolaryngoscope WINS with less

maneuvers

HS72

INTUBATION PROCESS

PARAMETERS SUMMARY

IDS

Videolaryngoscope WINS with less

than 1 score

HS73

INTUBATION PROCESS

PARAMETERS SUMMARY

CORMACK-LEHANE GRADE

Videolaryngoscope WINS with more

% of grade I

HS74

INTUBATION PROCESS

PARAMETERS SUMMARY

SUCCESSFULNESS

NS?

INTUBATION PROCESS

PARAMETERS SUMMARY

COMPLICATIONS

NS?

AND HERE IS THE ANSWER?

FAMILAR

ITY

Post-hoc inter-group analysis

Analyzed data represent high statistical significance

difference between groups (C and A) as regard

Number of attempts (p = 0.002),

Optimization (p = 0.001),

ID score (p = 0.001) and

only significant difference regarding

successfulness (p = 0.041).


By comparison of group (C vs M) there was

high statistical significance difference as regard

Number of attempts, Optimization, and ID

score (p values was 0.009, <0.001, and <0.001

respectively)

but there was NO significant difference as

regard successfulness between these two groups

(C vs M) (p = 0.169).


No statistical significance detected between groups

(A vs M) as regarding

Number of attempts (p = 0.842),

Optimization (p = 0.137),

ID score (p = 0.229)

successfulness (p = 0.315).


81

RESULTS OF THE STUDY

IDS DISTRIBUTION

Group C showed highest Mean±SD (3.38±2.14)

versus (0.14±0.35) and (0.32±0.68) in group A

and group M respectively.

Group C showed highest median among other

groups (3) versus (0) in groups M and A.

There was high significance difference in

distribution of IDS among three groups

(p<0.001).


IDS DISTRIBUTION


Cormack-Lehane score in each group

C&L of I; was highest in group A (98%)

followed by (12% and 74%) in groups C and M

respectively.

C&L of II; it was highest in group C (62%)

followed by (2% and 24%) in groups A, and M

respectively.

C&L of III; it disappeared in group A and

represented by (26% and 2%) in groups C and

M respectively.


Cormack-Lehane score in each group

85


numbers of attempts

Group A showed highest percentage of patients

that intubated in first attempt in comparison to

other groups (90%), versus (88%) and (62%) in

groups M and C respectively.

Group C had the highest percentage of patients

intubated from second attempt (28%) versus

(10% and 10%) when compared to groups A

and M respectively.

86


numbers of attempts

NO patients intubated by third attempt in group

A when compared to other groups

Group C showed highest Mean±SD (1.48±0.67)

vs ((1.1±0.3) (1.14±0.4)) in group A and group

M respectively, with highly significant data

difference among groups (p<0.001).

There was high significant data difference in

distribution of numbers of attempts in between

groups (p<0.002).


numbers of attempts


SUCCESSFULNESS

number of patients who were successfully

intubated in three groups which was highest in

group A (100%) followed by (98% and 92%) in

group M and group C respectively.

These data was of non-statistical significant.

89


SUCCESSFULNESS

90


HEART RATE

As regard Heart Rate:

non statistical significance between all groups

regarding change in heart rate in pre-intubation

time, or after intubation (at immediate post-

intubation, 1 and 5 minutes post-intubation).

But there were statistical significance upon

comparison of post-intubation with pre-

intubation data.

91


HEART RATE

92

AIRTRAQ LEAST

MACINTOSH MOST

As regard hemodynamics?

Heart rate:

AIRTRAQ

was less than other two laryngoscopes in

stimulation of heart rate

MAP:

Same distribution

No upper hand for any

Definition of intubation time

T1;from insertion of the device into the mouth till

optimal glottic view.

T2;from optimal glottic view till confirmation of

tracheal intubation (by vision).

behavior of laryngoscopes in

types of intubation time

T1;

behavior of laryngoscopes in

types of intubation time

T2;

When it comes to intubation

time?

THE RESULTS ARE:

HSEXCEPT SMALL

NS

When it comes to intubation

time?

100


Complications Occurrence

As regard frequency of complications :

non statistical significance between all groups

regarding presence or absence of complications

(p=0.135).

However there was high statistical significance

difference between occurrences of primary and

secondary complications between all groups (p=

0.006).



As regard occurrence frequency of 1ry and 2ry

complications:

There was high statistical significance between

groups A versus M (p< 0.003),

Statistical significant difference between groups

C versus M (p= 0.013),

But NO statistical significant difference between

groups C versus A (p=0.711).





SIMILAR RESULTS

ON SAME TOPIC

SYSTEMIC META-ANALYSIS

DISCUSSING VIDEOLARYNGOSCOPES

SYSTEMIC META-ANALYSIS

DISCUSSING VIDEOLARYNGOSCOPES

ARTICLES…….

LIMITATIONSDESIGN

operator knows the devices, which may also introduce bias.

(solved by closed envelopes basis).

STIMULATIVE

not on real cervical trauma patients.

FURTHERMORE………

inter-incisor distance may be added in airway assessment

parameters as pre and post insertion of neck collar especially

because it affects primary insertion of Airtraq VL.

RECOMMENDATIONS

This study recommends the use of

videolaryngoscopes in our daily practice to

increase its familiarity to users and specially

in difficult airway scenarios such as neck

immobilization situations because it

provide better airway management even

without extensive training, and it is needed

to conduct similar studies upon real cervical

trauma patients for better assessment of its

advantages and disadvantages.

TAKE HOME MESSAGE

INCORRECT INTUBATION

POSITIONING

(HYPEREXTENSION)

CORRECT INTUBATION

POSITION (NEUTRAL

POSITION)

THANK YOU

Health & Medicine

Airway management in stimulated cervical trauma scenarios