How many hypopneas were recorded?

How many hypopneas were recorded?

• A. 16
• B. 14
• C. 2
• D. 4

Answer: (A)

Hypopneas are partial drops in airflow during sleep that are counted only when they meet specific timing and physiologic change criteria. According to common scoring rules, a hypopnea is a change lasting at least 10 seconds with at least a 30% reduction in airflow, and it must be accompanied by either a 3% or greater drop in oxygen saturation or an arousal. To get the total number recorded, you simply tally every event that meets those criteria across the whole sleep study. In this case, the data show 16 events that satisfy the threshold for a hypopnea, so the hypopnea count equals 16. The other numbers would reflect fewer events meeting the criteria (for example, using a stricter desaturation threshold or failing to count arousals as qualifying events), which is why they’re not the total recorded here.

Hypopneas are partial drops in airflow during sleep that are counted only when they meet specific timing and physiologic change criteria. According to common scoring rules, a hypopnea is a change lasting at least 10 seconds with at least a 30% reduction in airflow, and it must be accompanied by either a 3% or greater drop in oxygen saturation or an arousal.

To get the total number recorded, you simply tally every event that meets those criteria across the whole sleep study. In this case, the data show 16 events that satisfy the threshold for a hypopnea, so the hypopnea count equals 16. The other numbers would reflect fewer events meeting the criteria (for example, using a stricter desaturation threshold or failing to count arousals as qualifying events), which is why they’re not the total recorded here.