The Science Journal of the American Association for Respiratory Care
A newly available self-titrating CPAP (continuous positive airway pressure) device (Tranquility Auto, Respironics, Inc.) titrates to therapeutic pressure by analyzing airflow patterns at different pressures for evidence of airflow limitation. To assess the accuracy of this technique and device, we performed sleep studies on 28 patients with confirmed obstructive sleep apnea (mean AHI = 55.3 ± 6.7), comparing sleep and respiratory patterns while treated with a manually titrated level of CPAP (night 1) or self-titrated CPAP using the Tranquility Auto (night 2). The mean CPAP generated by manual titration was 10.5 ± 2.8 cm H2O, while that generated by the Tranquility Auto was 10.6 ± 2.1 cm H2O (NS). The table demonstrates the respective effects upon total sleep time (TST), apnea-hypopnea index (AHI), arousal index (ARI), minimum O2 saturation (SaO2 min), and % TST below an SaO2 of 90% (% < 90%).
|TST||AHI||ARI||SaO2min||% < 90%|
None of these measures differed significantly between the manually titrated pressure and the Tranquility Auto. We found that the Tranquility Auto yielded CPAP levels that were similar to and as effective as manual CPAP titration. We conclude that this new self-titrating device will be useful for both determining appropriate levels of fixed CPAP and possibly for the ongoing home administration of CPAP therapy.