Moderator: Dr. Atul Sharma

Speaker: Dr. Misbah Salaria

DIFFICULT AIRWAY:ACCORDING TO ASA:- A clinical situation in which a conventionally

trained anesthesiologist experiences a difficultywith mask ventilation, difficulty with trachealintubation or both !

Difficult airway: spectrum Difficult :- Spontaneous/mask ventilation

LaryngoscopyTracheal intubationTracheostomy.

DIFFICULT MASK VENTILATION –

It is not possible for the unassisted anesthesiologist to maintain

SPO2>90% using 100% O2 and positive pressure mask ventilation in

a patient whose SPO2 was > 90% before anesthetic intervention

and/0r It is not possible for the unassisted anesthesiologist to prevent

or reverse signs of inadequate ventilation during positive pressure

mask ventilation

SIGNS OF DIFF MASK VENTILATION

Absent or inadequate chest movement.

Absent breath sounds.

Gastric air entry or dilatation.

Cyanosis.

Haemodynamic changes due to hypoxia or

hyper carbia.

Decreasing oxygen saturation.

Absent or inadequate exhaled CO2

• BEARD

• OBESITY WITH BMI > 26 KG/M2

• NOTEETH

• ELDERLY > 55YEARS

• SNORERS, H/O SLEEP APNEA

PATIENTS HAVING 2 OR MORE OF THE

ABOVE PREDICTORS LIKELY TO HAVE

DIFFICULT MASK VENTILATION.

PRECICTORS OF DIFF MASK VENTILATION (BONES)

DIFFICULT LARYNGOSCOPY-

•It is not possible for an unassissted anaesth. to visualize

any portion of the vocal cords with conventional

laryngoscopy .

DIFFICULT ENDOTRACHEAL

INTUBATION :

•Using conventional laryngoscopy , it takes >3 attempts to

insert an ETT and/or the insertion of an ETT requires>10

min. using conventional laryngoscopy.

1. Easy chin lift only

2. One person jaw thrust / mask seal.

3. As above + oropharyngeal or nasopharyngeal airway or both.

4. Two person jaw thrust / mask seal.

5. Two person jaw thrust / mask seal + airway.

6. Impossible mask ventilation despite maximal external effort & full use of airway (infinite)

Laryngoscopy performed by reasonably experienced laryngoscopist with the pt in optimal sniff position having no significant muscle tone & the laryngoscopist has an option of change of blade type & length.

1. Easy endotracheal intubation

2. One attempt, increasing lifting force.

3. As above + use better sniff position

4. Multiple attempts,external laryngeal pressure and multiple blades.

5. As above + multiple attempts by the laryngoscopist.

6. Impossible to intubate despite above maneuvers and using multiple blades. (infinite)

Intubation attempt if exceeds 30 seconds

Cyanosis or pallor if develops

Change in heart rate/rhythm if occurs (due to sympathetic stimulation)

Patient if develops significant hypoxia.

Respiratory events are most commonanesthetic related injuries

difficult face mask ventilation ~ 1:10,000

incidence of extreme difficult intubation:general surgery patients ~ 1:2000

obstetrics ~ 1:300

28% of anesthetic deaths are secondary due toinability to mask ventilate or intubate

History: previous records

General physical examination:(The combination of Mouth opening, jaw protrusion n head extension is the core of airway assessmment !)

ASSESSMENT OF TMJ: three ways: Mouth opening: >3 finger breadths or >5cm is

acceptable, <3cm gap- diff intubation in 95% TMJ mobility Mandibular protrusion;

Class A :Lower incisor protrude beyond upper incisor.Class B :Lower incisor at same level.Class C :Cannot protrude beyond upper incisor.Class B & C are associated with difficult airway.

Assesment of mandibular space : determine how easily laryngeal & pharyngeal axis will fall in line

Thyromental Distance(Patil`s test): >6.5cm- No problem with L & I6-6.5cm- Difficult laryngoscopy but possible

intubation

<6cm: Laryngoscopy impossible

Ratio of height to thyromental distance(cm)

>23.5 : easy laryngoscopy

HYOMENTAL DISTANCE: Between mentum & hyoid bone

Grade I: >6cm {Easy L & I} Grade II: 4-6 cm {difficult L & I} Grade III:<4cm {impossible L & I}

Sternomental distance: Head extention with mouth closed. Normal >12.5 cm. <12.5 cm :difficult L & I

Modified method :If inc. in length by 5 cm ---- easy L & I.If <5 cm ---- difficult L & I

Assesment of cervical & atlanto-occipital joint:Gives indication how easily a Sniffing position

will be acheived Neck flexion—25-35 degree & atlanto-occipital

joint extension—85 degree Measurement by visual estimate or goniometer

Grade I: no reduction of extensionGrade II: 1/3rd reductionGrade III: 2/3rd reductionGrade IV: complete reductionGrade III & IV are associated with difficult L & I.

THE EXAMINATION DESCRIBED BY EL-GANZOURI (mouth opening,

prognathic ability, head extension, thyromental distance and Mallampati test) is the most quantifiable of tests included in the ASA guidelines.

Patient in sitting position Head in neutral position Maximal tongue protrusion No phonation

SAMPSOON-YOUNG’S MODIFICATION (1987)added Class IV and correlated b/w ability to observeintraoral strucures and incidence of subsequentdifficult intubations.

• Visualisation of any part of epiglottis during MMP test

• Associated with easy laryngoscopy

• Difficult airway possible large epiglottis hinder laryngoscopic view as well as ventilation

CLASS ZERO MALLAMPATI

Class III or IV: signifies that the angle betweenthe base of tongue and laryngeal inlet is moreacute and not conducive for easy laryngoscopy

Limitations

Poor interobserver reliability

Limited accuracy

Good predictor in pregnancy, obesity,acromegaly

Grade 1:Full exposure of glottis (anterior + posterior commissure)

Grade 2: only the posterior extremity of glottis is seen

Grade3: no part of glottis n only the Epiglottis only

Grade 4: not even the epiglottis can be seen

On lateral X –ray of mandible & spine. Effective mandibular length(EML): Length b/w tip

of lower incisor & midpoint of TMJ. Posterior mandibular depth(PMD) : width b/w

alveolar margin & lower border of mandible immediately behind 3rd molar teeth.

If EML/PMD = <3.6 ….. Difficult intubation Mandibular angle : Nr =110—115 deg If < 106 or > 120 deg = difficult intubation Dec. in distance b/w occiput & spinous pricess of C1

<5cm or Inc. in posterior depth of mandible > 2.5 cm inc. chances of difficult airway.

1. X-Ray neck (lateral view) :

Occiput - C1 spinous process

distance< 5cm.

Increase in posterior mandible

depth > 2.5cm.

Ratio of effective mandibular

length to its posterior depth

<3.6.

Tracheal compression.

RADIOGRAPHIC

PREDICTORS

2. CT Scan:

Tumors of floor of mouth, pharynx, larynx

Cervical spine trauma, inflammation

Mediastinal mass

3. Helical CT (3D-reconstruction):

Exact location and degree of airway compression

• Flow volume loop

• Acoustic response measurement

• Ultra sound

• CT / MRI

• Flexible bronchoscope

ADVANCED INDICES

Weight

Tongue protrusion

Mouth opening

Upper incisor length

Mallampati class

Head extension

Any 3 indices if present

>80kg

< 3.2cm

<5cm

>1.5cm

>1

<70 degree

~Prolonged laryngoscopy

Group indices

Look at anatomy

Evaluate the airway

Mallampati

Obstructions

Neck mobility

Beard Short, fat neck Morbidly obese patients Facial or neck trauma Broken teeth (can lacerate balloons) Dentures Large tongue Protruding teeth A narrow or abnormally shaped face

If present, think of difficult airway

LEM

ONS

Will patients mouth open wide enough to accommodate 3 fingers?

Will 3 fingers fit between the mentum and hyoid bone?

Will 2 fingers fit between the hyoid and thyroid notch?

If not, expect a difficult intubation

LEM

ONS

LEM

ONS

Laryngoscopy or intubation may be more difficult in the presence of an obstruction Anatomy

Trauma

Foreign body obstruction

Edema (burns)

LEM

ONS

Ideally the neck should be able to extend backwardsProblems:

Cervical Spine ImmobilizationAnkylosing SpondylitisRheumatoid Arthritis

Neck Mobility:

PARAMETER 0 1 2

Wt(Kg) <90 =90 >90

Head/neck movement

>90 =90 <90

Interincisor gap

>5 cm =5 cm <5 cm

Sliding mandible

>0 =0 <0

Receeding mandible

none moderate severe

Buck teeth none moderate severe

<5:easy laryngoscopy

6-7:moderate difficulty

8-10:severe difficulty

Parameter evaluated Min accepted value significance

Interincisor gap >3 cm Easy laryngoscopy

Buck teeth No overriding Wrong direction

Upper incisor length <1.5 cm easy alignment

Voluntary mandibularprotrusion

Can be done Optimal TMJ fxn

Mallampati class < grade II EASY L & I

Palate No narrowing/arching Easy L & I

TM Distance >5cm Optimally placed larynx

Compliance of mandibular space

soft Easy compressibility of tongue

Neck thickness Obese neck Difficulty in aligning axes

Neck length Should not be short Difficulty in aligning axes

Head/neck mov Flex >35 or ext >80 3 axes best aligned

1 finger breadth for subluxation of mandible.

2 finger breadth for adequacy of mouth opening.

3 finger breadth for hyomental distance.

In emergency situation, above test can be rapidly performed within 15sec to assess the TMJ function,mouth opening and hyomentsl distance. Significant difficulty in 2 or more of these components requires detailed examination.

• 4 finger breath for thyromental distance

• 5 movements- ability to flex the neck upto the manubrium sterni, extension at the AOJ, rotation of the head along with right & left movement of the head to touch the shoulder.

Rule of 1-2-3-4-5

• 3 finger in the interdental space.

• 3 finger between mentum and hyoid bone.

• 3 finger between thyroid cartilage & sternum.

RULE OF 3THREE`S

Distance from the upper border of the manubrium

to the tip of mentum, neck fully extended, mouth

closed

Minimal acceptable value – 12.5 cm

Single best predictor of difficult laryngoscopy and

intubation ( Has high sensitivity & specificity).

Inter-incisor distance with maximal mouthopening

Normal value > 5-6.5 cm / admits 3 fingers.

Significance :

Positive results: Easy insertion of a 3 cm deepflange of the laryngoscope blade

< 3 cm: difficult laryngoscopy

< 2 cm: difficult LMA insertion

Affected by TMJ and upper cervical spine mobility

Significance-Class B and C: difficult laryngoscopy

Patient is asked to hold the head erect, facing directly to the front maximal head extension angle traversed by the occlusal surface of upper teeth(can also measured by goniometer).

Minimum 35⁰extension is possible at AOJ in normal individuals.

Attlanto.Occipital.Extension

Grade Reduction of A.O.Extension

1 none

2 One third

3 Two third

4 complete

Grades 3 and 4 : Difficult laryngoscopy

Grading of reduction in A.O.Extension

Grade I : > 35°Grade II : 22-34°Grade III : 12-21°Grade IV : < 12°

can also be done by asking the patient to look

at the floor and at wall after fully flexing and

fixing the neck as shown

• Flexion movement of the cervical spine can be assessed by asking the patient to touch his manubrium sternii with his chin. If done, the above maneuver assures a neck flexion of 25- 35 degree. Flexion and the extension movement if within the normal range ,three axis ( oral,pharyngeal & laryngeal axis) can be brought into a straight line.

Place the index finger of each hand, one underneath the

chin and one under the inferior occipital prominence

with the head in neutral position. The patient is asked

to fully extend the head on neck. If the finger under the

chin is seen to be higher than the other, there would

appear to be no difficulty with intubation. If level of

both fingers remains same or the chin finger remains

lower than the other, increased difficulty is predicted.

Palm print sign: Patient’s fingers and palms painted with blue ink and pressed

firmly against a white paper Grade 1- all phalangeal areas visible Grade 2- deficient interphalangeal areas of 4th and 5th digits Grade 3- deficient interphalangeal areas of 2nd to 5th digits Grade 4- only tips seen.

Prayer sign.

Limited-mobility joint syndrome(stiff-joint sydrome)

Type I diabetics positive "prayer sign“. TM joint and C-spine (e.g.atlanto-occipital joint) may be involved

A positive "prayer sign" can be elicitedon examination with the patient

unableto approximate the palmar surfaces ofthe phalangeal joints while pressingtheir hands together; this represents cervical spine immobility and the potential for a difficult endotracheal

intubation

C-spine immobilized trauma patient

Protruding tongue Short, thick neck Prominent upper incisors

(“buckteeth”) Receding mandible High, arched palate Beard

Dentures Limited jaw opening Upper airway conditions Face, neck, or oral trauma Laryngeal trauma Airway edema or

obstruction Morbidly obese MONTREAL SYSTEM OF

CLASSIFICATION IN PAEDIATRIC AGE GROUP FOR VARIOUS CHD’S

Anaesthesiologist :Inadequate preoperative assessment Inadequate equipment preparationInexperiencePoor technique

Equipment : Malfunction / Unavailability

Patient : Congenital & acquired causes.

CONGENITAL:-

Pierre Robin

Syndrome

Micrognathia, Macroglossia, Cleft soft

palate

Treacher Collins

Syndrome

Auricular & ocular defect, molar &

mandibular hypoplasia.

Goldenhar’s

Syndrome

Auricular and ocular defects, molar and

mandibular hypoplasia; occipitalization

of atlas.

Down’s Syndrome Poorly developed or absent bridge of the

nose, macroglossia

Klippel-Feil

Syndrome

Congenital fusion of a variable number

of cervical vertebrae; restriction of neck

movement, elevated scapula

ACQUIRED

Infections

Supraglottitis

Croup

Abscess

Ludwig’s angina

Laryngeal oedema

Laryngeal oedema

Distortion of the airway and trismus

Distortion of the airway and trismus.

Arthritis Rheumatoid

Arthritis

Ankylosing

spondylitis

TMJ ankylosis, deviation of restricted

mobility of Cervical spine.

Ankylosis of cervical spine, less

commonly ankylosis of TMJ; lack of

mobility of cervical spine.

Tumour

Benign Tumor

Malignant Tumor

Stenosis or distortion of the airway

Fixation of larynx to adjacent tissues.

Trauma Oedema of airway, unstable#,

haematoma

Obesity Short thick neck, sleep apnoea

Acromegaly Macroglossia, Prognanthism

Acute Burns Oedema of airway

MANAGEMENT OF DIFFICULT INTUBATION :

Correct position of the patient

- A pillow (10 cm) should be placed under the head but not under the shoulders.

- MORTON and colleagues (1989) proposed this position as lower neck flexion 35o and extension of the plane of face 15o (both angles relative to horizontal plane)

SIMPLE TECHNIQUES : (EQUIPMENTS)

i) Pressure on cricothyroid (SELLICK’S MAN.), thyroid cartilage or External laryngeal manipulation. - Knill postulated Backward, Upward and Rightward pressure known as BURP to the thyroid cartilage when the larynx is anterioly placed for improving the view.

ii) Stylet : - Elongated metal or plastic rod with a smooth surface and no sharp edges over which an ETT can be passed. - Should be stiff and flexible enough to change the shape and curve of the ETT. -Facilitate intubation by directing the tube tip towards the glottis.

iii) Guedel Airway

iv) Gum elastic Bougie or Tube Exchange Catheters.-used by Sir Robert Macintosh (1943) - Elongated; flexible,soft and smooth rods over which the ETT can be

passed but these can not alter the shape of ETT.- Useful when the posterior portion of the larynx is barely visible for the epiglottis can not be elevated. It is important to bend the distal end forward after it has been passed through the tracheal tube. The bougie can then be advanced blindly towards the cords and then the tube can be rail-roadedover the bougie.

v) - Hollow bougies are also available for attachment to oxygen

v) Magill forceps : Double angled forceps have grasping ends in the axis of ETT and handle at the right angle.

vi) Tube bender forceps (Aillon forceps) : These have unequal limbs which can bend the distal end of the ETT in the desired direction.

vii) Flexible lumen finder (Flexguide) : It is designed to be used with right hand after insertion through the ETT. It has a handle thumb ring, inner rod and notched outer tube. The distal tip of the tube can be manoeuvred with the help of the proximal thumb ring.

viii) Schroeder Stylet :

ix) Laryngoscope blade and handles : Bozzoni invented first laryngoscope in 1805.In 1907 Jackson designed a U-shaped laryngoscope with the

aim to divert force away from upper teeth.Two commonly used designs – the curved (Macintosh) and

the straight (Miller) blades.It is essential that the force applied to the laryngoscope

handle is directed along the long axis of handle.

1. Inadequate or malfunctioning equipment.

2. Not requesting for experienced help.

3. Exaggerated idea of personal ability

4. No discussion with colleagues about proposed management of the case .

5. Ill conceived plan (A) with no proper back up plan (B).

6. Even poorly conducted plan (A) or sticking extra time to the plan (A) so delaying the rescue plan (B).

7. Inexperianced staff

8. Poor technique

9. Inadequate pre operative assesment

Rigid laryngoscope blades Tracheal tubes Tracheal tube guides ( bougie, stylet,

lightwand, forceps) Airways (nasal & oral) Variety of facemasks(endoscopic masks) Elevation pillows Monitors Suction Oxygen (low & high flows) Pharmacological agents Supraglottic devices (LMA, Combitube) Video laryngoscope

Rigid indirect laryngoscopes Fibreoptic intubation equipment Retrograde intubation kit Non-invasive/minimally invasive airways Jelly & ointment Defogging solution Fibroptic intub airways Other supraglottic devices Rigid & Flexible Broncoscope Local anaesthtic spray Difficult airway algorithm Airway exchange catheters Surgical Airway

Signs

...absent chest movements

…dec.SpO2

…cyanosis

…absence of exhaled Co2

…absent breath sounds

…gastric air entry or dilatation

…hemodynamic changes

One person effort

Smallest possible facemask & with jaw thrust

Appropriate sized airway- oral or nasal

Esmarch Heiberg Maneuver:

… involves dorsiflection at atlanto-occipital joint & protusion of mandible anteriorly by exerting a forward thrust on the rami of mandible”

If both hands are needed ventilation can be achieved by squeezing bag between elbows & lateral abdominal wall or between knees till help arrives

Two person synergistic effort:

1st person acheives mask seal with one hand & squeezes bag with other hand while 2nd person provides jaw thrust or

• 1st person holds the mask with two hands while 2nd person squeezes the bag

Chin pressure on mask if continued leak

Leave artificial dentures in place

Packing buccal cavities with gauze

Large mask in edentulous patients

Employing a mask strap or tell assistant to pull sagging cheaks

Application of continuous +ive pressure of 5-10cmH20 while ventillating

Applying vaseline jelly over beard

LMA.

Combitube.

Lightwand.

Fibreoptic Intubation.

Trans Tracheal Jet Ventilation

Retrograde Intubation

Surgical Airway

If surgery is non emergent in nature,consider awakening the patient or returning to spontaneous ventilation

1. Short Neck.

2. Protruding incisor teeth.

3. High arched palate.

4. Poor mobility of neck.

5. Increase in either anterior depth or Posterior depth of the mandible.

6. Decrease in Atlanto Occipital distance.

Management:-

Use well lubricated malleable Stylet

Different blades of laryngoscope like Miller, Macintosh, Bullard & McCoy.

Gum elastic bougie

LMA or Combitude

Use of lightwands

If patient is being ventilated think of fiberoptic intubation

Blind nasotracheal intubation

If multiple attempts fail & case is not of emergent nature, it is best to ventilate the pt. until drugs can be reversed

SURGICAL AIRWAY :FINAL RESORT

…as one in which ventilation with noninvasive techniques fails to maintain oxygenation & tracheal intubation proves impossible

..this scenario may develop rapidly but often occurs after repeated unsuccessful attempts at intubation

Call for help Go for emergency non invasive airway

ventilation likeCombitude/LMA Rigid broncoscopeTTJV

In case of failure ---EMERGENCY INVASIVE AIRWAY ACCESS

Surgical or percutaneousTracheostomy or Cricothyrotomy

Basic preparation

~Inform~Ascertain help~Preoxygenation~Supplemental

oxygenation throughout

Portable storage unit

Rigid laryngoscope blades ETTs ETT guides-bougie LMAs FOI equipments Retrograde intubation kit Emergency non invasive

airway ventilation device. Emergency invasive airway

access Exhaled CO2 detector

Different lengths of blades Different types of blades Different positions Simple Bougie or light wand guided or with a

hollow for O2 Call for help Best attempt laryngoscopy

IN CASE OF AN UNANTICIPATED DIFFICULT INTUBATION

Can we Ventilate with a BMV? (Consider two NPA’s or a OPA, gentle Ventilation)

Two person ventilation?

LMA an Option? Or other supraglottic airway ?

LMA?

Combi -Tube?

Retrograde Intubation?

we should have an assistant at this stage

Plan “C”

Needle, Surgical or cannula cricothyroidectomy

TTJV

Tracheostomy

Try to wake up the patient from the time we fail intubation.

Backward, Upward, Rightward Pressure: manipulation of the trachea

90% of the time the best view will be obtained by pressing over the thyroid cartilage

Differs from the Sellick Maneuver

v) Magill forceps : Double angled forceps have grasping ends in the axis of ETT and handle at the right angle.

vi) Tube bender forceps (Aillon forceps) : These have unequal limbs which can bend the distal end of the ETT in the desired direction.

vii) Flexible lumen finder (Flexiguide) : It is designed to be used with right hand after insertion through the ETT. It has a handle thumb ring, inner rod and notched outer tube. The distal tip of the tube can be maneouvered with the help of the proximal thumb ring.

viii) Schroeder Stylet

ix) Laryngoscope blade and handles : Bozzoni invented first laryngoscope in 1805.In 1907 Jackson designed a U-shaped laryngoscope with the aim to divert force away from upper teeth.Two commonly used designs – the curved (Macintosh) and the straight (Miller) blades.It is essential that the force applied to the laryngoscope handle is directed along the long axis of handle.

Specialised curved blades 1- Left handed Macintosh blade - for left handed laryngoscopists

- For anatomical abnormalities on the right side of the face mouth and oral cavity.

2- Improved vision Macintosh blade

3- Polio Blade – The angle between the blade and the handle is made obtuse.

- It is useful in situations when the antero-posterior diameter of the chest is such that insertion of the laryngoscope into the mouth is difficult or impossible.

4. Laryngoscope with “stunted” or short handle : useful in

obese patients and in patients with large breast.

5. Oxiport Macintosh : It has an oxygen port in the blade

allowing oxygen insufflation during intubation attempts.

6. Tull Macintosh : This blade has a suction port.

7. Siker blade : has stainless steel mirrored surface which

permits visualisation of an “anterior” larynx. It gives an inverted

image.

8. Huffman Prism : Images are real.

- Prism should be placed in warm water for 30 sec on anti-fog

solution to prevent fogging

Shucman-Pro

Levering Laryngoscope

11. Upsher fibrecoptic laryngoscope – combines fibreoptic round

the corner viewing with maneuverability. 12. The tip of blade is advanced until it comes to rest close to the cords.

The tube sits in the semi-enclosed space in the blade. - The variable focus eye piece enables the operator to obtain uninterrupted

view of the procedure. The eye piece can be attached to T.V. Camera for teaching purposes.

13. Specialised straight bladesRacz-Allen blade, Choi blade,

Belscope blade, Bainton blade, Guedelblade, Bennett blade, Whitehead blade,Flagg blade, Eversole blade, Snow

blade.

WU SCOPE

Truview evo2 Laryngoscope Glidescope L with video

intubating system

AIRTRACH•Indirect rigid laryngoscopy•Minimum mouth opening required•Less hemodynamic stimulation compared to conventional L•Curvature n well designed optical components help I visualisation of the glottis without the need of alignment.

•Utilises the paraglossal technique of intubation

•BONFILS retromolar intubation fibrescope is a 5mm optical, distally curved stylet

which can accommodate a 6mm or larger ET tube

•Permits continuous oxygen insufflation

•Light supplied via remote Xenon source

•Can be attached to a module with image display

BLIND NASAL INTUBATION

Can be performed in anaesthetised or awake patients. - Position - sniffing the morning air position - A well lubricated nasal tube is gently passed through

the most patent nostril. - The nasal mucous membrane should be

constricted by the use of vasoconstrictor (xylometazoline or any other nasal decongestant). -The bevel of the tube should be pointing laterally so as to avoid trauma to choncha. -The tube is then advanced while listening to the breath sounds, manipulation of thyroid cartilage and at times of head facilitates the alignment of the tube.

- At times acute flexion of neck may be required if the obstruction occurs during passage of the tube.

- The tip of the tube may get placed at five positions –1.Into the trachea2. Against the anterior commissure 3. may abutt In the vallecula at the base of tongue. 4. Laterally into pyriform recess. 5. In the Oesophagus.

NASOTRACHEAL INTUBATION IS INDICATED IN INTRAORAL SURGERIES,LIMITED MOUTH OPENING, ANT LARYNX etc

STEPS :-

1. PSYCOLOGICAL PREP AND CONSENT2. PREMEDICATION3. LOCAL ANAESTHESIA OF THE AIRWAY4. PROCEDURE

DR. PETER MURPHY WAS THE FIRST TO USE FLEXIBLE FIBERSCOPE

Fiberoptic endotracheal intubation is a useful technique in a number of situations. It can be used when the patient's neck cannot be manipulated, as when the cervical spine is not stable. It can also be used when it is not possible to visualize the vocal cords because a straight line view cannot be established from the mouth to the larynx.

Fiberoptic intubation can be performed either awake or under general anesthesia and it can be performed either as the initial management of a patient known to have a difficult airway, or as a backup technique after direct laryngoscopy has been unsuccessful.

Principle • Internal reflection - Beam of light entering one

end of glass rod will repeated internally reflex off the walls of rod, eventually emerging from other end.

• Optical lenses – Light that is internally reflected is completely blurred. it is focused with a series ofoptical lenses.

• (Gold standard for anticipated difficult intubation) – any age, any position.

• Requires good experience.

FFI;- Bronchoscopes : Both rigid and fibreoptic

bronchoscopes have been used as an aid to intubation.

Flexible fibreoptic intubation. It consists of –

A. Insertion tube – Flexible part extending from control

section to distal tip of scope.

B. Control section – Contain the tip control knob which

controls movement of insertion tube.

C. Eye piece section.

D. Light transmission cord – from external light source to

hand of fiberscope.

E. Light source.

91

Lack of expertise (most common)

Secretion and blood

Fogging of lenses

Poor topical anesthesia

Distorted anatomy

Fiberoscope malfunction

Inadvertent passage of fiberoscope through Murphy’s eye

ADJUNCTS TO DIFFICULT AIRWAY MANAGEMENT –

1. Nasopharyngeal airway

2. Oesophageal Obturator Airway –By Don Michael and Gordon in 1968.

Consist of two parts first 30 cms plastic oesophageal tube occluded at distal

end.

- There are perforations in the tube which are intended to be located in

hypopharynx. A large balloon is located at distal end to create a seal in the

oesophagus.

- Second part of the device is face mask with an inflatable cuff designed to

make a tight seal with the face. After lubrication tube is inserted blindly

without laryngoscope.

Connell’s Nasopharyngeal Airway

Esophageal Obturator Airway

Purpose ___ maintain a patent airway

Adv. ___ dec. the work of breathing

How ?___lifts the tongue & epiglottisaway from the posterior

pharyngeal wall and prevent them from obstructing the space

• USES PATENCY OF AIRWAYprevent biting/occluding of ETTfacilitating suctioningobtains better mask fitinserting devices into oesophagus

3. Patils syracuse oral airway- allows fibreoptic intubation

4. Ovassapian fiberoptic intubating airway – Accommodates tracheal tube upto 9 mm diameter.

5. COPA (Cuffed Oropharyngeal airway )-Disposable device that combines a guided airway with an inflatable distal high volume lowpressure cuff and a proximal 15mm adapter. - distal tip should be behind base of tongue

6. Pharyngo-tracheal lumen airway - it is double lumen tubeconsisting of a long tube with a distal cuff (15 cc) designed to beinflated in esophagus and shorter tube that protrudes through thelarger tube and past alarge proximal cuff (100 cc) to ventillatethe lungs.

7. Oesophageal tracheal combi tube (OTC) :

- Disposable double lumen tube with a low volume inflatable distal

cuff and a larger proximal cuff.

- Distal cuff => Oesophagus Proximal cuff => Oropharynx

- Ventilation is possible with either tracheal or esophageal intubation.

If it enters oesophagus (common) – Ventilation is through multiple

proximal apertures situated above distal cuff. Both cuffs have to be

inflated. - If it enters trachea –ventillation is through distal lumen as

with a standard tracheal tube.

4.

• Is a non cuffed

supraglottic device with the

shape of the LMA

• Disposable

• Made of gel ,softer

• Has a gastric drain

(ProSeal LMA-like)

• Bite block

• And an epiglottis blocker

10. I GEL

“Pharyngeal Express” Airway

12.

Plastic disposable uncuffeddeviceAnatomically shaped to fit pharynx & forms a seal with the pharynxHollow boot with toe, heel & bridge with opening anteriorlyAvailable in 6 sizes(47,49,51, 52,55 &57 mm)Match with the width of thyriodcartilage

Bridge fits in pyriformfossa

Heel connects to airway tube(rectangular) , stablizeit & has color coded connector

Large chamber for storing regurgitated fluids

Toe has lateral bulges

Easy to insert & high first high attempt success rate

But more resistance to insertion

Used for both spontaneous & controlled ventilation

Well tolerated during recovery

PERILARYNGEAL AIRWAY (COBRAPLA)

Easy to insert & high successful first attempt rate

Used for percutaneous cricothyroidotomy

In difficult to ventilate & intubate scenario

In LMA failure as in neck contractures

DISADVANTAGE

Does not protect against aspiration

Nebulizers—entire airway {5ml of 4% lidocaine} Topical sprays—upper airway {10%lidocaine} Viscous gels_ upper airways {4% lidocaine } Trans tracheal injection —larynx and trachea {2-

3 ml of 2% lidocaine} “SAYG”—larynx and trachea Nerve blocks —distribution of the nerve supply Combinations of the above

Generally speaking, vocal cord and its vincity is the most sensitive site and the most common barrier to successful awake fiberoptic intubation; others are usually tolerable under the spray of local anesthetics.

AIRWAY BLOCKS:-

Glossopharyngeal Nerve Block

26# spinal needle

Advance 0.5 cm

into mucosa

2 BRANCHES : MOTOR N

SENSORY

2ml of 1~2% lidocaine

each side into tonsillar

pillors

Aspiration before injection

May have the patient in

sitting or back-up position

Block post 3rd of tongue &

oropharynx

Superior Laryngeal Nerve Block

Locate the hyoid bone • 1cm below each greater cornu (where the internal branch of the superior laryngeal nerve penetrates the thyrohyoid membrane) • Infiltrate 3ml 2% lignocaine • Feel a ‘pop’ as the needle penetrates the membrane

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The patient’s neck is slightly hyperextended.

Drug : 4% Lidocaine 2 ml of 10% at end expiration (2% needs longer onset time, maybe 10 min)

22G IVcath, through cricothyroid membrane,air bubbles after aspiration confirmcorrectplacement

Ask pt to cough

TTJI can provide o2 on a short term basis until definitive airway can b placed or the patient resumes spontaneous breathin or wakes up.

85

An oral bite is a must unless very good topical anesthesia (which is a rarity.)

Advance the tip of the scope(ETT mounted) till the posterior part of the tongue base then bend downwards nearly 90°; epiglottis will appear in view.

Advance between epiglottis and posterior wall of larynx. Glottic opening would be found.

Now advance the ETT on the scope & remove the scope

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A more curved pathway compared with nasal passage

Less convenient in distorted anatomy

Prone to deviate from midline position (an intubating airway is helpful.)

Easy to cause fiberoscope damage

~RI INVOLVES A PUNCTURE OF THE CRICOTHYROID MEMBRANE AND THE THREADING OF A WIRE RETROGRADE THROUGH THE VOCAL CORDS INTO THE MOUTH OR THE NOSE, WHICH GUIDES AN ETT THROUGH THE GLOTTIS.

~THIS IS TYPICALLY USED IN THE CANT VENTILATE, CANT INTUBATE SCENARIO!

IN CASE FIBEROPTIC TNTUBATION TOO FAILS, WE GO FOR {RETROGRADE INTUBATION}:-

EQUIPMENTS:-~SELF CONTAINED RI KITS ARE AVAILABLE~HOWEVER EQUALLY EFFECTIVE ASSEMBLY OF THE EQUIPMENT CAN BE DONE BY PROCURING A WIDE BORE NEEDLE OR TUOHY’S NEEDLE OR AN 18-16G INTRACATH, AN EPIDURAL CATHETER, A 5ML SYRINGE N A STERLISED MOSQUITO FORCEPS~EVEN A REAUTOCLAVED LONG LENGTH >50 CMS J-WIRE OF A CVP CAN BE USED OVER WHICH ET IS RAILROADED!

COMPLICATIONS:-TRACHEAL LACERATION, INFECTION AND MEDIASTINITIS

~ The retrograde technique of intubation consists of percutaneously passing a narrow flexible guide into the trachea from a site below the vocal cords and advancing this guide through the larynx and out the mouth or nose. In the basic technique, the tracheal tube is then passed over the guide through murphy’s eye into the upper part of the trachea, the guide is removed, and the tube is advanced into the trachea.

~Guides may emerge from the mouth or nose. If nasal intubation is planned and the guide comes out of the mouth, a soft catheter can be passed through the nose, retrieved from the mouth, and then used to bring the guide out through the nose.

~Passage of an epidural catheter through the larynx has been successful after failure with a guidewire, and it is easier to retrieve a plastic guide than a steel guidewire from the mouth. Guidewires are a better choice for use with the FFL. The technique can be performed under topical anesthesia in a sedated patient.

~The guides are inserted through a needle or cannula that is inserted horizontally (so that the vocal cords are not damaged) with the bevel directed cephalad. The intratracheal position of the initial needle should be confirmed by aspiration of air. Jaw thrust and tongue traction can facilitate passage of the guide behind the tongue.

ADVANTAGES CERVICAL SPINE FRACTURE PTS

SAFE ALTERNATIVE IF INTUBATION IS ANTICIPATED DIFFICULT OR IMPOSSIBLE

EFFECTIVE IN CASES OF FAILED INTUBATION WHERE BAG & MASK VENTILLATION IS ADEQUATE & TIME IS AVAILABLE

CAN BE DONE AWAKE OR IN ANAESTHTISED PTS

contraindications INFECTED NECK

NEOPLASTIC LARYNGEAL LESIONS

Injection of high velocity gas into the airway through a narrow cannula without a seal—60cyc/min

HFJV- >60 cyc/min Jet acts to inc volume delivered Needle cricothyrotomy In children peak pressure is set at 5psi-

increased by 5psi increments until adequate chest expansion

In adults-preset pressure 25psi, then decor inc depending clinically

Keep airway patent-sniff position & jaw thrust

If obstruction persists-go for tracheostomy Inspired 02 conc depends on structure of

catheter & ratio of catheter to trachea

Automatic ventilators

Manual jet ventilation

Auxilary flometer

Oxygen flush

Anaesthesia breathing system

Manual resuscitation bag

Indications (only if >10 years old)

Failed airway

Failed ventilation

Predictors of difficulty

Previous neck surgery

Obesity

Hematoma or infection

- Minitracheostomy is preferred. A single vertical incision 3-5 mm in

length over cricothyroid membrane is made and then through

obturator the 4 mm uncuffed tracheal tube is guided.

-Compared with I.V. cannula the minitrach has larger diameter and is

better for jet ventilation and even for assisted spontaneous

respiration for a short period.

MINI TRACHEOSTOMY

Indications1. Upper Airway Obstruction.

2. Pulmonary Ventilation.

3. Pulmonary Toilet.

4. Elective Procedure

Patient placed in supine position with pillow under shoulders & a head ring.

Prepare the area & drape.

Under local or general anaesthesia.

Give a transvrse insicionfavouribly

Gentle dissection

After retracting isthmus of thyriod gland upwards ,trachea is exposed

NS filled syringe is introduced & aspirate to confirm position

Window created in 3rd -5th tracheal rings

Tracheostomy tube inserted & secured

Intraopertaive Complications. Bleeding and injury to big vessels Injury to tracheoesophageal wall Pneumothorax

Early Complications Bleeding Tracheostomy tube obstruction Tracheostomy tube displacement

Infection

Late Complications Tracheal Stenosis Granulation tissue Tracheocutaneus fistula Tracheo - inominate fistula

Equipments:

Quicktrach IStandard-Set Available for adults (I.D. 4mm

children (I.D. 2mm) and

infants (I.D. 1.5mm)

Quicktrach II

Cricothyrotomy creates a percutaneous airway through the cricothyroid membrane. Its advantages over tracheostomy are that the membrane is superficial and relatively avascular and cartilage incision is not necessary because the height of the membrane is greater than the distance between the tracheal rings. Cricothyrotomy can be performed with a surgical or cannula (needle) technique, and appropriate use can prevent anesthetic-related deaths. It is a core skill for the anesthesiologist

Technology Based

• ETCO2 (monitor)

• Pulse Ox change

METHODS OF

CONFIRMATION

Traditional

• Direct

Visualization

• Lung Sounds

• Tube

Condensation

1….. MMP Class 3 or 4

2….Supraglottic and glottic areas oedema.

3….Large breasts.

4….Full dentition.

5….Mucosal congestion of nose, pharynx,etc.

6….Enlargement of tongue.7….Fat deposition in oropharyngeal region.

8….Elevation of hyoid bone.

9…..Weight gain.

10…Improperly applied cricoid pressure.

11…Improperly applied hip wedge causes decreased chin –chest distance.

Difficult spontaneous ventilation in obstructive sleep apnea

BMI > 26 – predicts difficult mask ventilation

Difficult intubation predictors-

MMP Score >3

Neck circumference >16inches

RSI involves 4 experienced personnel

AMPLE history

Allergies

Medication

Past medical history

time of Last meal

Events leading

safe cervical spine movement

Equipment option depending on operator experience & skill

• Manual in-line stabilization(MILS)

• Airway interventions requiring less neck movement

– Jaw-thrust (ventilation)

– Adjunctive device ILMA, combitube

– Cricothyrotomy

• Least movement (0.1 mm) with fibre optic nasal intubation

4.CERVICAL SPINE INJURY: MANAGEMENT OPTIONS

• Micrognathia is a common feature of difficult intubation in children• The most important consideration is whether ventilation by facemask will be possible.• Always have a plan A, B and C. • Whenever possible use an inhalational technique and keep the child breathing spontaneously• Repeated attempts using a technique which has failed has little logic. Alternative techniques should be considered. • Familiarize yourself with one technique of indirect laryngoscopy by practicing it in children with normal airways.

Cuff leak test, visual inspection n imaging of airway swelling!

LEAK TEST is performed in a spontaneously ventilating patient at risk of obstruction after extubation. Circuit disconnected occlusion of ETT end and deflation of cuff ability to breath around the ETT.

METHODS:-1.Conventional awake extubation2.Extubation over a bougie.3.Extubation over a fibreoptic bronchoscope.4. Endotracheal ventilation and exchange catheters

e.g. – Cook’s airway exchange catheter– Tracheal tube exchanger

-THE LARSONS MANEUVER :- Pressure on the laryngospasm notch is a non invasive, safe n often effective technique in the management of laryngospasm on extubation. Suxamethonium(0.5mg/kg) IS USED IN EXTUBATION INDUCED LARYNGOSPASMS.- Also it is a useful stimulant whenever there is respiratory depression after extubation.-Helium is of proven value in the management of post extubation stridor.-CROUP N LARYNGOSPASMS CONTRIBUTE A HIGHER RATE IN PAEDIATRIC DIFFICULT EXTUBATIONS.

-EXTUBATION RISK PATIENT:-Awaken the patient and wait for complete reversal of NMB-Should remain intubated in the intensive therapy until there is an evidence that airway swelling has resolved-Extubate over a ventilating stylet/tube exchange catheter-Factors such as altered neurological status may affect extubation n trachaeostomymay be needed-Extubation should not be performed in a patient at risk of vomitting or regurgitation.-It should b performed in an awake patient after breathing 100% oxygen to max o2 stores-Helium, non invasive ventilation and CPAP may reduce the need for reintubation!

• Use antisialogue in premedication.

• Aspiration prophylaxis.

• ET of assorted size.

• LMA of assorted size.

• Tracheostomy set.

• Check special airway equipment.

• Keep help of senior anaesthesiologist.

• Preoxygenate patient / End tidal CO2 device.

• Dont produce deep plane of anaesthesia.

• Dont use technique that you are not familiar.

• Avoid multiple attempts.

• Dont render the patient apnoeic, unless you are

certain that mask ventilation can be maintained

THANK YOU!