The primary pathophysiology underlying acute respiratory failure in a patient with head trauma involves

In a patient with head trauma, the primary pathophysiology underlying acute respiratory failure often involves hypercapnia due to decreased minute ventilation. Head trauma can impair the central nervous system's ability to regulate breathing, leading to inadequate ventilation and a build-up of carbon dioxide (CO2) in the blood. Other factors like shifting of the oxyhemoglobin dissociation curve, increased intrapulmonary shunt, and dehydration due to diabetes insipidus may be present but are not the primary causes. References: CCRN Exam Handbook, AACN, page 25, section on Respiratory.