Re: preoxygenation, reoxygenation, and delayed sequence intubation in the Emergency Department.

BACKGROUND The goal of preoxygenation is to provide us with a safe buffer of time before desaturation during Emergency Department intubation. For many intubations, the application of an oxygen mask is sufficient to provide us with ample time to safely intubate our patients. However, some patients are unable to achieve adequate saturations by conventional means and are at high risk for immediate desaturation during apnea and laryngoscopy. For these patients, more advanced methods to achieve preoxygenation and prevent desaturation are vital. DISCUSSION We will review the physiology of hypoxemia and the means to correct it before intubation. Next, we will discuss apneic oxygenation as a means to blunt desaturation and the optimal way to reoxygenate a patient if desaturation does occur. Last, we will discuss the new concept of delayed sequence intubation, a technique to be used when the discomfort and delirium of hypoxia and hypercapnia prevents patient tolerance of conventional preoxygenation. CONCLUSIONS These new concepts in preoxygenation and reoxygenation may allow safer airway management of the high-risk patient.