Tracheal Intubation and Airway Management

Question 1

What are the indications for tracheal intubation?

Answer 1

1. Upper airway obstruction
2. Respiratory failure
   - Inadequate oxygenation
   - Inadequate ventilation
   - Elevated work of breathing
3. Airway protection

Question 2

Why is upper airway obstruction an indication for tracheal untubation?

Answer 2

Avoid life threatening hypoxaemia
- Upper airway is obstructed and cannot be opened by maneuvers

Question 3

Evaluation of hypoxaemia for intubation

Answer 3

1. Oxygen saturation < 90% despite on non-rebreather mask (NRM)
2. Check cardiac output adequacy
3. Haemoglobin concentration
4. Any chronic hypoxaemia and its reasons
   (right-to-left shunts - will never have 100% saturation)

Question 4

Evaluation of hypoventilation for intubation

Answer 4

1. Respiratory acidosis and type 2 respiratory failure (CO2 retention), narcosis
2. Low pH can cause myocardial irritability and reduced contractility
3. Any chronic CO2 retention

Question 5

Evaluation of work of breathing for intubation

Answer 5

Normal - respiratory muscles consume < 5% of total body oxygen consumption

In abnormal - can go as much as 40%
- Accessory respiratory muscle
- Paradoxical respiration
- Fatigue and muscle failure

Question 6

Evaluation of airway protection for intubation

Answer 6

1. AMS - loss of protective airway reflexes, risk of aspiration
2. Airway collapse

Question 7

Cricoid pressure maneuver

Answer 7

Minimises aspiration risk

Firm pressure on cricoid cartilage
- Occludes oesophagus
- Reduces gastric distention from mask ventilation
- Reduces gastric regurgitation

Question 8

Mallampati Class

Answer 8

I - soft palate, fauces, entire uvula, tonsillar pillars
II - soft palate, fauces, part of uvula
III - soft palate, base of uvula
IV - soft palate not visible at all

Question 9

Thyromental distance

Answer 9

Normal: 35 degree extension of atlanto-occipital joint

Thyromental distance - measurement of distance from chin to thyroid cartilage
< 6.5cm - predicts difficult intubation

Question 10

Confirmation of tracheal intubation

Answer 10

1. 4-point auscultation of bilateral breath sounds (upper and lower), and absent of stomach inflation
2. CO2 capnography
3. Direct/video laryngoscopic view

Question 11

Complications of tracheal intubation

Answer 11

1. Dental injury
2. Cervical spine injury
3. Pharyngeal and laryngeal trauma
4. Gastric aspiration
5. Tracheal rupture

Question 12

ETT to carina distance

Answer 12

Neutral: 5cm +/- 2 above the carina
Flexed: 3cm +/-2 above the carina
Extended: 7cm +/-2 above the carina