While ventilating a patient with a set peak inspiratory pressure of 20 cmH₂O, the physician order you to increase the PEEP from 5 to 10 cmH₂O. Based on the above change the tidal volume will decrease.

Correct Answer: A

Rationale: In pressure control ventilation, increasing PEEP from 5 to 10 cmH₂O with a fixed PIP of 20 cmH₂O reduces the pressure gradient (PIP - PEEP) from 15 to 10 cmH₂O, decreasing tidal volume.

Correct Answer: B

Rationale: Venous blood has a lower pH than arterial due to higher CO₂ levels from tissue metabolism.

Correct Answer: D

Rationale: Without the ECG, the answer key indicates 'd'. Third-degree AV block shows complete dissociation between P waves and QRS complexes.

Correct Answer: A

Rationale: The correct answer is providing room air. Endotracheal tubes are used to maintain an open airway in clients who are unable to breathe on their own. Providing room air ensures that the client is receiving sufficient oxygenation. Communicating frequently with the client and rapidly assessing nasal and oral mucosa for redness and irritation are important nursing interventions, but they are not specific to clients with endotracheal tubes.

Correct Answer: C

Rationale: Pulse oximetry measures arterial oxygen saturation (SpO2) non-invasively.