Airway Management

Question 1

Indications for airway management

Answer 1

Intubation is indicated for patients at risk for aspiration and those undergoing surgical procedures involving body cavities or the head&neck.
Mask ventilation or LMA are sufficient for short minor procedures like cystoscopy and inguinal hernia repair

Question 2

Techniques for airway management

Answer 2

Jaw thrust and chin lift to open airway.
Artificial airway inserted in mouth or nose.
Alignment of 3 axis's: oral, pharyngeal, laryngeal (flexion of lower cervical spine ~35degrees and extension of upper cervical spine ~80 degrees).
Face mask ventilation.
ETT
Esophageal-tracheal combitube
Nasotracheal intubation
Flexible Fiberoptic Nasal intubation

Question 3

Describe how to evaluate the airway

Answer 3

1. Mouth opening at least 2 large finger breadths
2. oropharynx: Mallampati classification and Largyngoscopy grade
3. Thyroid - mandibular distance: greater than 6cm, 3fingers
4. TMJ subluxation - 1 finger
5. Neck Mobility

Question 4

Mallampati classification

Answer 4

Class I - soft palate, all uvula, fauces, anterior and posterior tonsillar pillars
Class II - soft palate, fauces, part of uvula
Class III - soft palate, base of uvula
Class IV - hard palate only

Question 5

Laryngoscopy grade

Answer 5

a. Grade I: complete glottis visible
b. Grade II: anterior glottis NOT seen
c. Grade III: epiglottis seen, but not glottis
d. Grade IV: epiglottis NOT seen

Question 6

Nerve to mucous membrane of nose

Answer 6

ophthalmic division V1 anteriorly (anterior ethmoidal n.) and maxillary division V2 posteriorly (sphenopalatine n.)

Question 7

Tongue sensation innervation

Answer 7

Lingual n. (branch of V3) and glossopharyngeal n.

Question 8

Tongue taste innervation

Answer 8

VII and glossopharyngeal n.

Question 9

Roof of pharynx, tonsils, undersurface of soft palate innervation

Answer 9

glossopharyngeal n.

Question 10

Sensation to airway below epiglottis innervation

Answer 10

vagus n.

Question 11

Larynx below vocal cords and trachea innervation

Answer 11

recurrent laryngeal n.

Question 12

cricothyroid m. innervation

Answer 12

external laryngeal n. (branch of superior laryngeal n.)

Question 13

Superior Laryngeal nerve injury

Answer 13

If unilateral - minimal effect

If bilateral - hoarseness, tiring of voice, but airway control NOT jeapardized

Question 14

Recurrent Laryngeal nerve injury

Answer 14

If unilateral - hoarseness
If bilateral - acutely: stridor, respiratory distress (because unopposed tension of cricothyroid m. innervated by intact superior laryngeal n.). Chronic - aphonia = cant speak, less frequent airway problems because of compensation (atrophy of laryngeal musculature)

Question 15

Vagus nerve injury

Answer 15

If unilateral - hoarseness

If bilateral - aphonia, but airway control rarely a problem

Question 16

Causes of difficult mask ventilation

Answer 16

poor mask fit, short neck, obesity, lack of teeth, facial distortion, airway/neck or mediastinal mass, radiation therapy to airway or neck, multiple intubation attempts, airway trauma

Question 17

Causes of difficult intubation

Answer 17

short neck, receding mandible, prominent upper incisors, narrow/high arched palate, limited mouth opening; macroglossia, cleft palate, vascular compression, various syndromes; RA (cervical instability, cervical fusion), temporomandibular dz, cricoarytenoid fibrosis, radiation to head and neck; infxn/neoplasms – retropharyngeal abscess, epiglottis, laryngeal tumors, cystic hygroma, mediastinal masses; acromegaly; trauma

Question 18

What to do if can’t intubate

Answer 18

reestablish mask ventilation, rearrange head position, try different blades, call for help, alt. techniques (mask vent, intubation assist devices, LMA, asleep fiberoptic intub), awaken pt., surgical airway

Question 19

Equipment needed to support & augment ventilation

Answer 19

A. Laryngoscopes (Macintosh [tip insert in vallecula] and Miller [cover epiglottis]), endotracheal tubes, stylet, syringe for balloon, O2, ambu bag, mask, suction, monitors (SpO2 & EtCO2), assistant,
Flexible fiberoptic bronchoscopes (FOB)

Question 20

How to identify upper airway obruction in unconscious patient

Answer 20

high breathing-circuit pressures w/ minimal chest mvt and breath sounds

Question 21

Ways to relieve obstruction in unconscious patient

Answer 21

1. Have assistant help you so that two or three hands can be used in a jaw thrust maneuver.
2. Try using an oral or nasal airway
3. If due to laryngospasm, remove offending stimulus (e.g. oral nasal airway, secretions like saliva/blood/vomitus), apply continuous positive airway pressure, deepen anesthetic state and use rapid-acting m. relaxant. Don’t use sux if wheelchair bound/burns/hospitalized patients (upregulation of nicotinic receptors, therefore when sux given will get more hyperkalemic)
4. Adjust and possibly reinsert tracheal tube/LMA

Question 22

How to monitor adequacy of ventilation (important!)

Answer 22

A. Auscultation for presence bilateral breath sounds
B. Chest movement
C. EtCO2 (gold standard), SpO2
D. Fogging up of tube/mask

Question 23

Physiological response to intubation

Answer 23

HTN and tachycardia (up to 10 min), laryngospasm caused by stimulation of superior laryngeal n., bronchospasm, increased intracranial (CNS) and intraocular P (eye), GI – regurg and aspiration.
Treat laryngospasm: O2 with continuous positive airway pressure and small dose rapidly acting m. relaxant if necessary

Question 24

Common complications during intubation

Answer 24

hypoxia, hypercarbia, dental and airway and cervical spine trauma, tube malpositioning, tube malfunction, hemorrhage, trauma to eye, pharyngeal/tracheal dissection, esophageal intubation, aspiration gastric contents/foreign body, main stem intubation

Question 25

Common complications while intubated

Answer 25

blockage of tube, aspiration, displacement tube, rupture trachea/bronchus

Question 26

Common complications post intubation

Answer 26

sore throat, glottic edema, vocal cord paralysis, infxn, laryngeal ulcer/granuloma, tracheomalacia/stenosis

Question 27

Describe a typical induction sequence

Answer 27

A. Preoxygenation or denitrogenation for 5 minutes or four vital capacity breaths over 30 sec: replace lung nitrogen w/ O2 to provide a reservoir of oxygen that will continue to be diffused across the alveolar capillary bed after onset of apnea. Buys 4 extra minutes (room air, desat

Question 28

What is rapid-sequence-induction (RSI)?

Answer 28

IV induction drug followed by rapidly acting neuromuscular blocking drug (w/o performing positive pressure ventilation) and then direct intubation

Question 29

Describe the indication for rapid-sequence-induction (RSI)

Answer 29

If there is high risk of aspiration (full stomach or don’t know last time patient ate, delayed gastric emptying, bad GERD, abdominal obstruction/ileus, ), morbidly obese patient, acute trauma, >12 week pregnant