What is the minimum duration for an apnea event to be counted?

What is the minimum duration for an apnea event to be counted?

• A. 5 seconds
• B. 10 seconds
• C. 15 seconds
• D. 20 seconds

Answer: (B)

Ten seconds is the threshold used to count an apnea. In AASM scoring, an apnea means a complete cessation of airflow for at least 10 seconds. This duration choice helps ensure that only meaningful breathing pauses are counted, avoiding very brief pauses that can occur naturally during sleep. If airflow stops for less than 10 seconds, it isn’t counted as an apnea. The way the body’s effort behaves during that pause determines whether the event is labeled obstructive, central, or mixed, but the 10-second rule applies to all types. For contrast, a hypopnea involves a partial reduction in airflow for at least 10 seconds, typically with a desaturation or arousal, not a complete stop.

Ten seconds is the threshold used to count an apnea. In AASM scoring, an apnea means a complete cessation of airflow for at least 10 seconds. This duration choice helps ensure that only meaningful breathing pauses are counted, avoiding very brief pauses that can occur naturally during sleep. If airflow stops for less than 10 seconds, it isn’t counted as an apnea. The way the body’s effort behaves during that pause determines whether the event is labeled obstructive, central, or mixed, but the 10-second rule applies to all types. For contrast, a hypopnea involves a partial reduction in airflow for at least 10 seconds, typically with a desaturation or arousal, not a complete stop.