Randomized controlled trial of noninvasive positive pressure ventilation (NPPV) versus servoventilation in patients with CPAP-induced central sleep apnea (complex sleep apnea)

Abstract

Study objectives: To compare the treatment effect of noninvasive positive pressure ventilation (NPPV) and anticyclic servoventilation in patients with continuous positive airway pressure (CPAP)-induced central sleep apnea (complex sleep apnea).

Design: Randomized controlled trial.

Setting: Sleep center.

Patients: Thirty patients who developed complex sleep apnea syndrome (CompSAS) during CPAP treatment.

Interventions: NPPV or servoventilation.

Measurements and results: Patients were randomized to NPPV or servo-ventilation. Full polysomnography (PSG) was performed after 6 weeks. On CPAP prior to randomization, patients in the NPPV and servoventilator arm had comparable apnea-hypopnea indices (AHI, 28.6 ± 6.5 versus 27.7 ± 9.7 events/h (mean ± standard deviation [SD])), apnea indices (AI,19 ± 5.6 versus 21.1 ± 8.6 events/h), central apnea indices (CAI, 16.7 ± 5.4 versus 18.2 ± 7.1 events/h), oxygen desaturation indices (ODI,17.5 ± 13.1 versus 24.3 ± 11.9 events/h). During initial titration NPPV and servoventilation significantly improved the AHI (9.1 ± 4.3 versus 9 ± 6.4 events/h), AI (2 ± 3.1 versus 3.5 ± 4.5 events/h) CAI (2 ± 3.1 versus 2.5 ± 3.9 events/h) and ODI (10.1 ± 4.5 versus 8.9 ± 8.4 events/h) when compared to CPAP treatment (all P < 0.05). After 6 weeks we observed the following differences: AHI (16.5 ± 8 versus 7.4 ± 4.2 events/h, P = 0.027), AI (10.4 ± 5.9 versus 1.7 ± 1.9 events/h, P = 0.001), CAI (10.2 ± 5.1 versus 1.5 ± 1.7 events/h, P < 0.0001)) and ODI (21.1 ± 9.2 versus 4.8 ± 3.4 events/h, P < 0.0001) for NPPV and servoventilation, respectively. Other sleep parameters were unaffected by any form of treatment.

Conclusions: After 6 weeks, servoventilation treated respiratory events more effectively than NPPV in patients with complex sleep apnea syndrome.

Trial registration: ClinicalTrials.gov NCT01609244.

Keywords: CPAP; NPPV; central sleep apnea; complex sleep apnea; servo-ventilation.

Figure 1

Patient flow, allocation to and dropout from the two treatment arms (noninvasive positive pressure ventilation (NPPV) and servoventilation).

Figure 2

Polysomnographic tracing of a patient who developed complex sleep apnea during continuous positive airway pressure treatment. The screenshot represents a period of 5 min where periodic central apneas are marked in red within the flow channel, corresponding desaturations are displayed in the oxygen saturation (SaO₂) channel and are marked in red.

Figure 3

Trend of the respiratory parameters of the two randomized arms that differed significantly at the end of the treatment period. Sigificance was determined by one-way analysis of variance. Post hoc analysis was carried out using the Scheffé procedure in case of equal variances and the Games-Howell test in case of unequal variances. CPAP, continuous positive airway pressure; NPPV, noninvasive positive pressure ventilation.