Kettering Therapist Multiple-Choice (TMC) Practice Exam

After aortic valve replacement, it’s critical to monitor the patient’s respiratory status closely, especially given the scenario of respiratory acidosis indicated by the arterial blood gas (ABG) results. In this case, increasing the frequency of ventilatory support is the most appropriate action.

Respiratory acidosis commonly results from inadequate ventilation, which means the patient is unable to effectively eliminate carbon dioxide (CO2). By increasing the frequency of breaths delivered by the ventilator, the respiratory therapist can effectively increase the minute ventilation, which can help to decrease the CO2 levels in the blood and improve the patient's acid-base balance.

The other choices could potentially exacerbate the situation. Decreasing the tidal volume would reduce the amount of air the patient receives with each breath, which could worsen hypoventilation and lead to further respiratory acidosis. Adjusting the FiO2 aims primarily at addressing hypoxemia rather than correcting hypercapnia, which is the primary concern here. Switching to pressure control ventilation may be beneficial in some contexts but doesn't directly address the immediate need to improve minute ventilation in the face of respiratory acidosis.

Therefore, increasing the frequency of breaths is the most effective means of helping address the respiratory acidosis in this situation, allowing for more carbon