Treatment-emergent central sleep apnea resolves with lower inspiratory pressure

Study objectives: Treatment emergent central sleep apnea (TECSA) is an important problem during therapy with continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA). Here we tested a device designed to improve CPAP comfort through reducing IPAP ($\dot{\text{V}}$-Com) to determine if such a reduction in IPAP could eliminate central apneas in patients with TECSA. Since increasing tidal volume (potentially via IPAP increments) has been suggested as a possible mechanism contributing to TECSA onset, our hypothesis was that reducing IPAP would yield a drop in the central apnea index (CAI).

Methods: The addition of a known resistance ($\dot{\text{V}}$-Com device) that reduces IPAP was implemented into the CPAP circuit during the second half of CPAP titrations in a cohort of community-dwelling patients who developed TECSA during a split-night CPAP titration. CAI was quantified from the sleep periods without and with $\dot{\text{V}}$-Com in place.

Results: 1613 patients underwent CPAP titration with 19 of them developing TECSA during the titration. The addition of $\dot{\text{V}}$-Com resulted in complete resolution of TECSA in all patients with adequate sleep data under all conditions (N=13), yielding a significant reduction in the CAI (17.3 ± 11.0 vs. 1.5 ± 1.7 events/h without and with $\dot{\text{V}}$-Com, respectively, P<0.001).

Conclusions: $\dot{\text{V}}$-Com virtually resolved all instances of TECSA, suggesting that reducing IPAP could be an effective strategy for managing the occurrence of central respiratory events in OSA patients using CPAP.