oxygen desaturation
A decrease in blood oxygen saturation levels, commonly measured during sleep studies.
Full Definition
Oxygen desaturation refers to a reduction in the percentage of hemoglobin saturated with oxygen in the blood, typically measured via pulse oximetry during sleep studies. In sleep medicine, desaturations of 3-4% or more from baseline are considered clinically significant and often accompany apneic events. The oxygen desaturation index (ODI) quantifies the number of significant desaturations per hour of sleep. Severe desaturations (below 80-85%) indicate substantial physiological stress and increased cardiovascular risk. Patterns of desaturation help distinguish between different types of sleep-disordered breathing.
Usage
Usage note: Specify percentage drop when clinically relevant; 3-4% is the typical threshold.
In Context
- "The patient experienced oxygen desaturations to 76% during REM sleep episodes." — Sleep study findings
- "Significant oxygen desaturation accompanied each apneic event on the overnight recording." — Polysomnography interpretation