Critical Care Nursing Cardiac Questions

Correct Answer: B

Rationale: The correct answer is B: Cardiac output (CO) of 4 L/min. In this scenario, the patient is presenting with signs of pulmonary congestion and hypoxemia, indicating possible cardiogenic pulmonary edema. As the cardiac output is a key indicator of how well the heart is functioning and delivering blood to the body, a low cardiac output can lead to inadequate tissue perfusion and worsen the patient's condition. Therefore, immediate action is required to address the low cardiac output to improve tissue perfusion and oxygenation. Choices A, C, and D are incorrect as they do not directly address the primary concern of inadequate cardiac output in this patient. Cardiac index, pulmonary vascular resistance, and systemic vascular resistance are important parameters to monitor, but in this case, the priority is to address the low cardiac output to improve the patient's condition.

Correct Answer: A

Rationale: The correct answer is A. A decrease in the arterial pressure (hypotension) with a low diastolic pressure (46 mmHg) may indicate inadequate perfusion, possibly due to inadequate cardiac output from the mechanical ventilation. This suggests that a change in ventilator settings may be required to improve oxygenation and perfusion. Option B is incorrect because a heart rate of 58 beats/minute alone does not provide direct information on the patient's hemodynamic status. Option C is incorrect as an increased stroke volume would usually be a positive indicator; it does not necessarily indicate a need for changing the ventilator settings. Option D is incorrect as a stroke volume variation of 12% is within normal limits and does not necessarily require a change in ventilator settings.

Correct Answer: C

Rationale: The correct answer is C: Pressure support ventilation. This mode delivers a set pressure to support each spontaneous breath, decreasing the workload of breathing. Pressure support ventilation assists the patient's inspiratory efforts without providing a set tidal volume like in volume-targeted ventilation. Continuous positive airway pressure (Choice A) maintains a constant level of positive pressure throughout the respiratory cycle but does not actively support spontaneous breathing efforts. Positive end-expiratory pressure (Choice B) maintains positive pressure at the end of expiration to prevent alveolar collapse but does not directly support spontaneous breathing. T-piece adapter (Choice D) is a weaning device that allows the patient to breathe spontaneously without ventilatory support.

Correct Answer: A

Rationale: The correct answer is A: Increase functional residual capacity. Positive end-expiratory pressure (PEEP) helps increase the functional residual capacity by keeping the alveoli open at the end of expiration. This prevents alveolar collapse, improves ventilation-perfusion matching, and enhances oxygenation. B: Prevent collapse of unstable alveoli - This is incorrect because PEEP actually helps prevent the collapse of all alveoli, not just unstable ones. C: Improve arterial oxygenation - This is partially correct, but the primary mechanism through which PEEP improves oxygenation is by increasing functional residual capacity. D: Open collapsed alveoli - This is incorrect because PEEP helps prevent alveolar collapse rather than actively opening already collapsed alveoli.

Correct Answer: C

Rationale: The correct answer is C: Teach the patient the reason for the use of prophylactic antibiotics. This is the most important action because human bites can introduce harmful bacteria into the wound, leading to infection. Prophylactic antibiotics help prevent infection in deep human bite wounds. Choice A is incorrect because rabies immune globulin is not indicated for human bite wounds. Choice B is incorrect because suturing human bite wounds can trap bacteria and increase the risk of infection. Choice D is incorrect because keeping the wounds dry is not sufficient; proper wound cleaning and antibiotic treatment are essential in this case.