不同类型面罩对慢性阻塞性肺疾病无创正压通气效果的影响

目的观察不同类型面罩对无创正压通气效果的影响。方法选择8例慢性阻塞性肺疾病(COPD)并呼吸衰竭患者，采用交叉自身对照试验，应用自行改良的双流向面罩及惯用面罩各通气1小时，两者间隔30分钟。在相同通气参数状态下，比较两种面罩通气效果。结果2组通气治疗后气促和呼吸费力改善，动脉血气pH升高、心率和呼吸频率显著降低（P<0.05或P<0.01）。改良面罩组动脉血二氧化碳分压(PaCO

Effect of twoway face mask on improving CO2 elimination during noninvasive ventilatory support in chronic obstructive pulmonary disease

Objective:To evaluate the benefit of selfdesigned twoway facemask on CO2 elimination in hypercapnic chronic obstructive pulmonary disease (COPD) patients compared with the convention almask.Methods:A randomized crossover study was conducted in 8 stable hypercapnic COPD patients.Each patient received noninvasive ventilatory support with selfdesigned twoway face mask and conventional mask for 1 hour in randomized order,with 30 minutes rest between each trial.Arterial blood gas (ABG) analysis was performed immediately before and at the end of each v entilation.Results:In twoway mask group,PaCO2 decreased from (9.79±1.73)kPa to (8 .21±1.95)kPa and pH increased from 7.34±0.05 to 7.41±0.08.In the conven tional mask group,PaCO2 decreased from (9.54±2.56)kPa to (8.77±2.14)kPa and pH in creased from 7.34±0.08 to 7.39±0.09.The improvement in PaCO2 〔ΔPaCO2 :(1.58±1.08)kPa〕 and pH (ΔpH:0.07±0.04) were significantly more marked i n the twoway mask group than in the conventional mask group 〔ΔPaCO2：(0.77±1.41) kPa, ΔpH:0.04±0.04,both P<0.05〕. Conclusions:By reducing the CO2 rebreathing, twoway facemask can improve the efficacy of CO2 elimination during noninvasive ventil atory support in hypercapnic COPD patients.