[Automatic positive airway pressure in titration and treatment of the obstructive sleep apnea syndrome]

Although continuous airway pressure therapy (CPAP) represents the standard treatment for obstructive sleep apnea syndrome (OSAS) auto-adjusting CPAP (APAP) devices were developed which adapt the treatment pressure to the actual requirement of the patients. The aim of automatic CPAP therapy is to improve the patients' acceptance of positive pressure treatment. The devices react to respiratory flow, flattening of the inspiratory flow contour, snoring, generator speed or the upper airway impedance. In recent years several studies showed that auto CPAP effectively treats respiratory disturbances, improves sleep profile and the self-assessment of the patients equally as good as the gold standard constant CPAP. Moreover, APAP reduces the treatment pressure substantially. Although an improvement of the patient's compliance has not consistently been proven, most patients prefer APAP versus constant CPAP. APAP devices use different algorithms depending on the primary purpose of the application. Therefore, a clear distinction between automatic titration and treatment is of major relevance. While titration devices aim at the finding of one single pressure which is fixed to a constant CPAP device, automatic treatment means the chronic use of APAP at home for optimal adaptation of the treatment pressure to the actual requirements of the patient. A high constant CPAP level, huge pressure variability, insufficient compliance with constant CPAP may be indications for APAP treatment. The main reason for automatic titration is the standardisation of the initiation process.