NBRC Critical Care and ABG Interpretation 2

Question 1

A patient on mechanical ventilation has a sudden decrease in SpO2 and a shift of the trachea to the unaffected side. The most likely diagnosis is:

Accepted Answer

Tension pneumothorax

Answer

Tension pneumothorax causes tracheal deviation away from the affected side, hypotension, absent breath sounds, and severe hypoxia — a life-threatening emergency.

Question 2

Systemic inflammatory response syndrome (SIRS) criteria include all of the following EXCEPT:

Accepted Answer

SpO2 <88% on room air

Answer

SIRS criteria include temperature, heart rate, respiratory rate/PaCO2, and WBC count abnormalities; SpO2 below 88% is not a SIRS criterion.

Question 3

Prone positioning in ARDS improves oxygenation primarily by:

Accepted Answer

Redistributing blood flow to better-ventilated dorsal lung regions and recruiting dependent lung

Answer

Prone positioning recruits previously collapsed dorsal (posterior) alveoli and redistributes perfusion to better-ventilated regions, improving V/Q matching and oxygenation.

Question 4

A pulmonary artery catheter (Swan-Ganz) wedge pressure (PAWP) of 25 mmHg suggests:

Accepted Answer

Left ventricular failure and pulmonary venous hypertension

Answer

Elevated PAWP (>18 mmHg) reflects high left atrial filling pressure from left ventricular failure, indicating cardiogenic pulmonary edema.

Question 5

Septic shock is defined as sepsis PLUS:

Accepted Answer

MAP <65 mmHg despite adequate fluid resuscitation requiring vasopressors, with lactate >2 mmol/L

Answer

Septic shock (Sepsis-3 definition) requires vasopressor use to maintain MAP ≥65 mmHg and serum lactate >2 mmol/L despite adequate fluid resuscitation.

NBRC - National Board for Respiratory Care Practice Test

NBRC - National Board for Respiratory Care Practice Test

NBRC Critical Care and ABG Interpretation 2