Osmolar gap metabolic acidosis in a 60-year-old man treated for hypoxemic respiratory failure.

A 60-year-old African-American man presented to the emergency department with malaise, fever, and mild shortness of breath. Following initial evaluation and application of supplemental oxygen, the patient was admitted to a step-down unit. Seventytwo hours following admission, his respiratory status declined, and he was transferred to the medical ICU. Following this transfer, endotracheal intubation, and initiation of positive-pressure ventilation with a fraction of inspired oxygen of 0.6 and positive endexpiratory pressure of 10 cm H2O, the patient was oxygenating poorly and was increasingly agitated. To control agitation and minimize peak inspiratory pressures, the patient was sedated with lorazepam by bolus and infusion dosing. After additional bolus doses of lorazepam and escalation of the infusion rate to produce deep sedation, he was paralyzed with cis-atricurium besylate to facilitate inverse ratio ventilation. Other medications administered included trimethoprim-sulfamethoxazole, prednisone, sucralfate, flutamide, glipizide, and acyclovir.