preoxygenated

Preoxygenated is a term used in medicine and aviation to describe the process of increasing the concentration of oxygen in a patient's or individual's lungs before a specific procedure or event. This is typically achieved by having the person breathe a higher than normal concentration of oxygen, often 100% oxygen, for a period of time.

In a medical context, preoxygenation is commonly performed before endotracheal intubation, anesthesia induction, or during procedures where airway obstruction is anticipated. The goal is to create an oxygen reservoir in the lungs, which can extend the time an individual can tolerate apnea (cessation of breathing) or hypoventilation without becoming hypoxic (lacking sufficient oxygen). This allows medical professionals more time to manage the airway and perform necessary interventions safely. Preoxygenation can be delivered via a non-rebreather mask, nasal cannula, or during positive pressure ventilation.

In aviation, preoxygenation is often implemented for pilots and crew members before flight at high altitudes. At these altitudes, atmospheric oxygen levels are lower, making it difficult to maintain adequate oxygen saturation. Preoxygenation helps to saturate the blood and tissues with oxygen before exposure to the lower partial pressure of oxygen at altitude, reducing the risk of hypoxia. This practice is particularly important for flight crews who may be performing demanding tasks and require optimal cognitive function.