What SpO2 decrease is recommended to score an event as a hypopnea?

What SpO2 decrease is recommended to score an event as a hypopnea?

• A. 2%
• B. 3%
• C. 4%
• D. 5%

Answer: (B)

Hypopnea scoring requires a partial reduction in airflow for at least 10 seconds, plus a desaturation that meets a defined threshold (or an arousal). The recommended SpO2 decrease to count an event as a hypopnea is 3%. This means that when airflow drops by about 30% for 10 seconds, a desaturation of 3% or more (or an accompanying arousal) makes the event a hypopnea. A smaller drop, like 2%, doesn’t meet the criterion, while a 4% drop also qualifies, but 3% is the minimum threshold used.

Hypopnea scoring requires a partial reduction in airflow for at least 10 seconds, plus a desaturation that meets a defined threshold (or an arousal). The recommended SpO2 decrease to count an event as a hypopnea is 3%. This means that when airflow drops by about 30% for 10 seconds, a desaturation of 3% or more (or an accompanying arousal) makes the event a hypopnea. A smaller drop, like 2%, doesn’t meet the criterion, while a 4% drop also qualifies, but 3% is the minimum threshold used.