An unresponsive 72-year-old male with known severe chronic obstructive pulmonary disease arrives at the triage area via ambulance. His wife, who accompanied him, reports a 24-hour history of escalating breathlessness culminating in extreme lethargy this morning. Vital signs obtained immediately upon transfer to the resuscitation bay demonstrate a temperature of 37.1°C (98.8°F), blood pressure of 158/92 mm Hg, heart rate of 118/min, and a respiratory rate of 8/min characterized by shallow excursions. Pulse oximetry indicates an oxygen saturation of 81% on room air. The patient only withdraws from painful stimuli and cannot answer questions. Chest auscultation reveals globally decreased air entry and faint expiratory wheezing. Which of the following represents the single most urgent initial step in this patient's clinical management?
- AMeasurement of arterial blood gases
- BStat computed tomography angiography of the chest
- Placement of an endotracheal tubeCevap
- DApplication of noninvasive positive pressure ventilation
- EDelivery of an intravenous naloxone bolus