A mixed apnea is characterized by which of the following?

A mixed apnea is characterized by which of the following?

• A. A combination of hypopnea and obstructive characteristics
• B. A lack of respiratory effort at the start of the event where respiratory effort returns before the event ends
• C. Respiratory effort present at the start of the event where the effort ceases in the second half of the event
• D. Intermittent respiratory effort throughout an obstructive event

Answer: (B)

A mixed apnea combines central and obstructive features within one event. It starts with no respiratory effort (a central component), and then the respiratory effort returns before the end of the event (an obstructive component). This sequential change—absence of effort at onset followed by the return of effort before the event finishes—best captures the mixed pattern. Other descriptions don’t fit as well: mentioning hypopnea focuses on partial airflow reduction rather than the change in respiratory effort that defines mixed apnea; stating effort is present at the start and then ceases describes a different pattern; and describing intermittent effort throughout doesn’t reflect the characteristic shift from no effort to resumed effort within a single event.

A mixed apnea combines central and obstructive features within one event. It starts with no respiratory effort (a central component), and then the respiratory effort returns before the end of the event (an obstructive component). This sequential change—absence of effort at onset followed by the return of effort before the event finishes—best captures the mixed pattern.

Other descriptions don’t fit as well: mentioning hypopnea focuses on partial airflow reduction rather than the change in respiratory effort that defines mixed apnea; stating effort is present at the start and then ceases describes a different pattern; and describing intermittent effort throughout doesn’t reflect the characteristic shift from no effort to resumed effort within a single event.