Bi-level positive airway pressure treatment of obstructive sleep apnoea syndrome.

We evaluated the effect of non-invasive nocturnal ventilation with the bi-level positive airway pressure (BiPAP) ventilator in 12 overweight patients with verified obstructive sleep apnoea syndrome (OSAS) and nocturnal hypercapnia. All patients exhibited subsequently less overnight CO2 accumulation (p < 0.0001), the desaturation event frequency was reduced (p < 0.002), daytime O2 tension rose (p < 0.001), daytime CO2 tension was reduced (p < 0.01), and apnoeas were eliminated. All symptoms characterising the syndrome, when present at the beginning of the therapy, were eliminated during the treatment. Patient compliance was high. This study showed that OSAS patients with hypercapnia can be effectively treated by BiPAP ventilation during sleep.