DCAS Airway Management & Intubation 4 — Questions and Answers
Question 1: The laryngeal mask airway (LMA) does NOT provide:
- Protection against aspiration of gastric contents (Correct answer)
- An open airway
- A conduit for ventilation
- Ability to administer oxygen
Correct answer: Protection against aspiration of gastric contents
The LMA sits in the hypopharynx above the larynx without cuffing the trachea, providing a patent airway and ventilation conduit but offering no protection against regurgitation and aspiration.
Question 2: Adequate pre-oxygenation before RSI aims to achieve a SpO2 of:
- 100% (or as close as possible) on high-flow oxygen for at least 3 minutes to maximise oxygen reserve (Correct answer)
- 90% is sufficient
- 70% is acceptable in emergency RSI
- Pre-oxygenation is not required in emergency airway management
Correct answer: 100% (or as close as possible) on high-flow oxygen for at least 3 minutes to maximise oxygen reserve
Pre-oxygenation denitrogenates the functional residual capacity, extending the apnoea time (safe apnoea period) before desaturation; achieving SpO2 100% maximises the oxygen reserve available during the intubation attempt.
Question 3: Which induction agent used in RSI has the property of maintaining haemodynamic stability and providing bronchodilation?
- Ketamine (Correct answer)
- Etomidate
- Propofol
- Midazolam
Correct answer: Ketamine
Ketamine's sympathomimetic properties increase heart rate and blood pressure (via catecholamine release), providing haemodynamic stability in shock states; it also causes bronchodilation making it ideal for intubation of asthmatic patients.
Question 4: The 'sniffing position' for intubation aligns:
- The oral, pharyngeal, and laryngeal axes to provide the best laryngoscopic view (Correct answer)
- The trachea parallel to the floor
- The patient's chin to the ceiling
- The ETT with the right main bronchus
Correct answer: The oral, pharyngeal, and laryngeal axes to provide the best laryngoscopic view
The sniffing position (neck flexed, head extended) aligns the oral-pharyngeal-laryngeal axis, improving the laryngoscopic view of the glottis; a folded towel under the occiput achieves this in most adults.
Question 5: Following intubation of a trauma patient with suspected haemopneumothorax, SpO2 suddenly drops. The first action is:
- Disconnect BVM and verify tube position — listen for bilateral breath sounds (Correct answer)
- Increase ventilation rate
- Administer epinephrine
- Perform immediate cricothyrotomy
Correct answer: Disconnect BVM and verify tube position — listen for bilateral breath sounds
Post-intubation desaturation has multiple causes (oesophageal intubation, right main bronchus, tension pneumothorax, haemothorax); systematically checking tube position first (DOPE: Displacement, Obstruction, Pneumothorax, Equipment failure) guides definitive management.
Question 6: The King LT or i-gel supraglottic airway is considered a 'second-generation' SGA because it:
- Incorporates a gastric drainage channel reducing aspiration risk compared to first-generation SGAs (Correct answer)
- Has two separate inflation balloons
- Can only be used for patients under anaesthesia
- Requires special training unavailable to paramedics
Correct answer: Incorporates a gastric drainage channel reducing aspiration risk compared to first-generation SGAs
Second-generation SGAs include a gastric drain channel through which a gastric tube can be passed to decompress the stomach and reduce regurgitation risk — an advantage over classic LMAs which lack this feature.
DCAS Airway Management & Intubation 4
The laryngeal mask airway (LMA) does NOT provide: