NBRC Mechanical Ventilation 2

Question 1

The lung-protective ventilation strategy for ARDS recommends tidal volumes of:

Accepted Answer

6 mL/kg ideal body weight

Answer

The ARDSNet protocol demonstrated improved survival with tidal volumes of 6 mL/kg IBW compared to conventional 12 mL/kg volumes.

Question 2

Which waveform is characteristic of volume-controlled, constant-flow ventilation?

Accepted Answer

Square (constant) flow waveform

Answer

Volume control with constant flow produces a square (rectangular) flow waveform, resulting in a linearly increasing pressure waveform.

Question 3

A patient's peak airway pressure suddenly increases with no change in plateau pressure. This suggests:

Accepted Answer

Increased airway resistance (e.g., bronchospasm, secretions)

Answer

A rise in peak pressure with unchanged plateau pressure indicates increased airway resistance because resistance affects dynamic (peak) but not static (plateau) pressure.

Question 4

Permissive hypercapnia in ARDS management allows PaCO2 to rise to reduce:

Accepted Answer

Barotrauma and volutrauma from aggressive ventilation

Answer

Permissive hypercapnia accepts elevated PaCO2 to enable lower tidal volumes and pressures, minimizing ventilator-induced lung injury.

Question 5

Which mode is most appropriate for weaning a patient from mechanical ventilation?

Accepted Answer

Pressure support ventilation (PSV) with gradually reduced support

Answer

PSV weaning allows clinicians to progressively reduce inspiratory support as the patient's spontaneous breathing strength improves, facilitating a smooth transition to extubation.

NBRC - National Board for Respiratory Care Practice Test

NBRC - National Board for Respiratory Care Practice Test

NBRC Mechanical Ventilation 2