Evaluation and comparison of Tranquility and AutoSet T autotitrating CPAP machines

The objective of this study was to determine the effectiveness of two autotitrating continuous positive airway pressure (auto-CPAP), the Tranquility (Respironics, Inc., Murrysville, PA, U.S.A.) and the AutoSet T (ResMed Corp., Poway, CA, U.S.A). Patients with obstructive sleep apnea syndrome (OSAS) underwent attended auto-CPAP titration with either the Tranquility or AutoSet T machine. The auto-CPAP machine was given a performance score between 0 and 9. A score of 3 or lower indicated that autotitration had to be discontinued. Sixty patients were studied, 35 patients with the Tranquility machine and 25 patients with the AutoSet T machine. The mean age was 55.4 years, whereas the mean body mass index (BMI) was 32.7. The mean respiratory disturbance index (RDI) was 37.5, and the mean arousal index before use of auto-CPAP was 41.4. The two treatment groups were comparable in age, BMI, RDI, and arousal index. The mean performance scores for the Tranquility and AutoSet T machines were not statistically different. Autotitration with the Tranquility machine had to be discontinued in 10 of the 35 patients (29%), whereas with the AutoSet T machine, autotitration was discontinued in 11 of the 25 patients (44%). Despite advances in auto-CPAP machines, there remains a large minority of patients with OSAS in whom these machines do not accomplish treatment goals. At this time, these machines are not a substitute for in-laboratory CPAP titration polysomnograms.