Average volume assured pressure support auto-EPAP(AVAPS-AE) mode for AECOPD patients with obesity hypoventilation syndrome (OHS)

Objective: To evaluate the role of noninvasive ventilation with AVAPS-AE mode in acute exacerbation of COPD patient with OHS. Methods: A randomized, prospective and controlled study. We included 66 patients: the majority(75.8%,n=50) is male; BMI:34.5±3.4kg/m2. Depending on ventilation mode, all subjects were divided(1:1:1) into 3 groups: S/T group, AVAPS group and AVAPS-AE group. Settings in 3 groups respectively: S/T mode(IPAP/EPAP:20/10cmH2O, TV depending on individual BMI); the similar parameters in AVAPS mode; AVAPS-AE mode(maximum EPAP=16cmH2O, minimum EPAP=6cmH2O). During NIV, degree of patients’ comfort was measured by VAS (Visual Analog Scale). Results: There was a higher VAS score of patients in AVAPS-AE group than others(p 0.05).48-hour intubation rate: 31.8%(n=7) in S/T group, 22.7%(n=5) in AVAPS group, 13.6%(n=3) in AVAPS-AE group respectively(p>0.05). Occurrence of patient-ventilator asynchrony in AVAPS group versus AVAPS-AE group:（45.4%(n=10) vs. 13.6%(n=3),p=0.021）. Conclusions: For AECOPD patients with OHS, AVAPS-AE mode could improve clinical symptoms quickly, especially in comfort of patients during NIV, we suggest that strategy for EPAP set in NIV should be a varying range rather than a fixed parameter, which maybe contribute to relieve dynamic hyperinflation of acute exacerbation of COPD patients with OHS.