A 3-year-old boy presents with multiple-system trauma. The child was an unrestrained passenger in a high-speed motor vehicle crash. On primary assessment, he is unresponsive to voice or painful stimulation. His respiratory rate is 5/min, heart rate and pulses are 170/min, systolic blood pressure is 60 mm Hg, capillary refill is 5 seconds, and SpO2 is 75% on room air. Which action should you take first