Airway, Respiration, and Ventilation Flashcards

A laryngeal mask airway (LMA) provides which level of airway protection?

Answer: Supraglottic airway — no aspiration protection

The LMA sits above the glottis (supraglottic) and does not provide protection against aspiration of gastric contents.

When performing rapid sequence intubation (RSI), succinylcholine is selected as the paralytic agent. A contraindication to succinylcholine is:

Answer: Suspected crush injury 48 hours old

Succinylcholine causes potassium release from muscle cells; in crush injuries older than 24-48 hours, this can cause life-threatening hyperkalemia.

A patient has stridor and a barking cough following upper respiratory infection. This presentation is MOST consistent with:

Answer: Croup (laryngotracheobronchitis)

Croup presents with a characteristic 'seal bark' cough, stridor, and low-grade fever after a viral URI, typically in young children.

Hypercapnia (elevated CO2) causes which of the following physiologic effects?

Answer: Respiratory acidosis and vasodilation

Elevated CO2 dissolves in blood to form carbonic acid, causing respiratory acidosis, and also acts as a potent vasodilator.

Which of the following is the CORRECT method for sizing an oropharyngeal airway (OPA)?

Answer: From the corner of the mouth to the earlobe

An OPA is sized by measuring from the corner of the patient's mouth to the earlobe (or center of mouth to angle of jaw), ensuring proper fit.

During endotracheal intubation, the vocal cords are best visualized using which laryngoscope blade design?

Answer: Curved (Macintosh) blade placed in the vallecula

The curved Macintosh blade is placed in the vallecula and lifting indirectly elevates the epiglottis to expose the cords.

Pulse oximetry may give a falsely HIGH reading in which of the following situations?

Answer: Carbon monoxide poisoning

Pulse oximetry cannot distinguish between oxyhemoglobin and carboxyhemoglobin, so CO poisoning produces falsely normal or elevated SpO2 readings.