Which symptom is characteristic of central sleep apnea during apneic periods?

Which symptom is characteristic of central sleep apnea during apneic periods?

• A. Loud snoring during sleep
• B. Rapid eye movements during sleep
• C. Absence of chest wall and abdominal movements during apneic periods
• D. Elevated SpO2 during apnea

Answer: (C)

Central sleep apnea is defined by a temporary loss of respiratory drive, so during apneic events there is no ventilatory effort at all. That means the chest wall and abdominal muscles do not contract, resulting in an absence of chest wall and abdominal movements during the apnea. This lack of effort is what sets CSA apart from obstructive sleep apnea, where airflow stops but the respiratory muscles still work, so you would still see chest and abdominal movements despite the obstruction. So the best indication here is the absence of these movements during apnea because it directly reflects the brain’s failure to initiate breathing, which is the hallmark of central events. The other options don’t fit CSA: loud snoring usually points to airway obstruction with ongoing effort, rapid eye movements during sleep are just part of sleep stages, and SpO2 would typically fall during an apnea rather than elevate.

Central sleep apnea is defined by a temporary loss of respiratory drive, so during apneic events there is no ventilatory effort at all. That means the chest wall and abdominal muscles do not contract, resulting in an absence of chest wall and abdominal movements during the apnea. This lack of effort is what sets CSA apart from obstructive sleep apnea, where airflow stops but the respiratory muscles still work, so you would still see chest and abdominal movements despite the obstruction.

So the best indication here is the absence of these movements during apnea because it directly reflects the brain’s failure to initiate breathing, which is the hallmark of central events. The other options don’t fit CSA: loud snoring usually points to airway obstruction with ongoing effort, rapid eye movements during sleep are just part of sleep stages, and SpO2 would typically fall during an apnea rather than elevate.