Automatic nasal continuous positive airway pressure titration in the laboratory: patient outcomes

Manual titration of nasal continuous positive airway pressure (NCPAP) treatment for obstructive sleep apnoea (OSA) is time consuming and expensive. There are now "intelligent" NCPAP machines that try to find the ideal pressure for a patient by monitoring a combination of apnoeas, hypopnoeas, inspiratory flow limitation, and snoring. Although these machines usually find similar pressures to skilled technicians, it is not clear if their use in the sleep laboratory influences subsequent acceptance by patients. This study addresses this question.

One hundred and twenty two patients undergoing a trial of NCPAP were randomly allocated to either manual or automatic (Horizon, DeVilbiss) titration of pressure during their first night on NCPAP in a hospital sleep laboratory. The primary outcome (available on 112 patients) was the acceptance of NCPAP or otherwise six weeks following the initial titration night. Baseline indicators of severity were compared between the groups, as were the pressures selected and the subsequent improvement in the sleepiness of the patients.

The initial severity of OSA was not significantly different in the two groups and the mean (SD) NCPAP pressures were similar (manual 8.7 (2.5) cm H2O, automatic 8.2 (2.1) cm H2O). The percentage of patients successfully established on CPAP at six weeks was 64% and 73% for the manual and automatic groups, respectively; 13% and 2%, respectively, in the manual and automatic groups had given up completely (p < 0.05), and there were about equal numbers (23% versus 25%) in the two groups who were still undecided.

The substitution of automatic NCPAP titration for manual titration during the first night of NCPAP in patients with OSA does not reduce the number accepting the treatment at six weeks and may slightly improve it. This has important cost saving potential.