Preoxygenation for Emergency Intubation: Longer Is Not Better

In critically ill patients, 3 to 5 minutes of preoxygenation with 100% oxygen through a resuscitator bag and mask is often recommended for patients who are spontaneously breathing and will undergo emergency intubation (JW Emerg Med Dec 1 1999). Researchers compared the effect of preoxygenation times of 4 versus 8 minutes on PaO₂ in 34 patients in an intensive care unit who had preexisting arterial lines and required emergent or urgent intubation after noninvasive methods of hypoxia treatment failed. Arterial blood gas was measured during noninvasive management (baseline) and during preoxygenation at 4, 6, and 8 minutes. Investigators positioned patients to optimize airway patency and provided preoxygenation with 100% oxygen at 15 L/minute u…