How many central apneas were recorded?

How many central apneas were recorded?

• A. 2
• B. 4
• C. 14
• D. 16

Answer: (A)

Central apneas occur when both airflow and respiratory effort stop for at least 10 seconds. To determine the count, you review the recording for episodes where the airflow signal goes flat and there is no chest or abdominal movement for a minimum of 10 seconds. In this tracing, two such periods meet those criteria, so two central apneas were recorded. The other numbers would require more episodes meeting the same definition, or would involve periods where effort remains or changes, which would indicate obstructive or mixed apneas rather than central.

Central apneas occur when both airflow and respiratory effort stop for at least 10 seconds. To determine the count, you review the recording for episodes where the airflow signal goes flat and there is no chest or abdominal movement for a minimum of 10 seconds. In this tracing, two such periods meet those criteria, so two central apneas were recorded. The other numbers would require more episodes meeting the same definition, or would involve periods where effort remains or changes, which would indicate obstructive or mixed apneas rather than central.