夜间无创正压通气对高原地区肺心病缓解期慢性呼吸衰竭患者的康复效应

背景药物治疗慢性呼吸衰竭的效果有限;采用无创通气对慢性肺心病慢性呼吸衰竭患者进行干预,可能不失为一种改善其症状和体征的有效措施.目的观察夜间无创正压通气对高原地区慢性肺心病缓解期慢性呼吸衰竭患者的呼吸肌功能、肺功能的作用.设计完全随机分组设计,对比观察.单位解放军第四医院兰州军区呼吸内科中心.对象选择2002-10/2004-11在解放军第四医院兰州军区呼吸内科中心住院的慢性肺心病缓解期慢性呼吸衰竭患者60例,男38例,女22例.患者均知情同意参加.随机分为2组,治疗组和对照组各30例.方法1]治疗组采用呼吸机治疗,时间为每晚2200～次日晨700,通气模式为压力支持通气和呼气末正压.在治疗前和治疗5周后测定肺功能、动脉血气、呼吸肌功能和6 min步行距离.对照组病情缓解1周后在出院前测定上述指标,出院后未经任何治疗,5周后复诊测定上述指标.2]6 min步行距离试验让患者尽最大努力在20 m走廊内行走,完成6 min或以呼吸困难不能坚持为止,用计量表测算步行距离.用电脑膈肌功能测定仪测定口腔最大吸气压、最大呼气压后,用气道阻断法测定最大跨膈压.采用血气分析仪测定动脉血氧分压和二氧化碳分压.用电脑肺功能仪测定第1秒用力呼气量占预计值百分比、第1秒用力呼气量占用力肺活量百分比.3]组间比较采用t检验,组内比较采用配对t检验.主要观察指标两组干预前后呼吸肌功能、肺功能、动脉血气和6 min步行距离比较.结果纳入慢性肺心病缓解期慢性呼吸衰竭患者60例均进入结果分析.两组患者干预前动脉血气和肺功能各项指标相近(P＞0.05).干预5周后,动脉血氧分压、第1秒用力呼气量占预计值百分比、第1秒用力呼气量占用力肺活量百分比、最大吸气压、最大呼气压、最大跨膈压和6 min步行距离治疗组治疗后明显高于治疗前和对照组治疗后(P＜0.05～0.01),动脉血二氧化碳分压治疗组治疗后明显低于治疗前和对照组治疗后(P＜0.01).结论夜间无创正压通气治疗能显著改善高原地区肺心病缓解期慢性呼吸衰竭患者的动脉血气和肺功能,增强呼吸肌力量.

Rehabilitation effect of nocturnal noninvasive positive pressure ventilation on respiratory failure in patients with stable chronic cor pulmonale at high altitude area

BACKGROUND: Medicine treatment of chronic respiratory failure achieved little effect. Interfering chronic respiratory failure of chronic cor pulmonale with noninvasive positive pressure ventilation (NIPPV) may be an effective measure to eliminate symptom and physical sign of patients.OBJECTIVE: To investigate the effect of nocturnal noninvasive positive pressure ventilation (NIPPV) on respiratory muscle function, pulmonary function of chronic respiratory failure patients with stable chronic cor pulmonale at high altitude area (HACCP).DESIGN: A completely randomized grouping design and randomized control trial.SETTING: Center of Respiratory Medicine, the 4th Hospital of Lanzhou Military Area Command of Chinese PLA.PARTICIPANTS: Totally 60 HACCP patients with chronic respiratory failure in stable stage, 38 male and 22 female, were admitted to Department of Respiratory Disease, the 4th hospital of Chinese PLA from October 2002 to November 2004. All cases, after informed consent was obtained,were randomly divided into two groups, including treatment group and control group with 30 cases in each group.METHODS: 1] Treatment group: Fitted with ventilator with pressure support ventilation (PSV) mode or positive end-expiratory pressure (PEEP)mode from 22:00 to next 7:00 every night. Before and after 5 weeks therapeutics, pulmonary function, arterial blood gas, respiratory muscle function and 6-minute walking distance (6MWD) were measured. Control group:Those were either assessed in inpatient objects stabled at least 1 week as control group before discharged and 5 weeks thereafter. 2] 6-minute walking distance (6MWD) test: Patients made their effects to walk 6 minutes in20 meters long corridor, or could not go on because of dyspnea, walking distance was determined. Using electronic diaphragmatic function meter,oral maximal inspiratory pressure (PImax) and maximal expiratory pressure(PEmax) were determined, then maximal transdiaphragmatic pressure (Pdimax) was measured with airway block method. With blood gas analyzer,partial pressure of oxygen in arterial blood (PaO2) and partial pressure of carbon dioxide in arterial blood (PaCO2) were assessed. With electronic spirometre, forced expiratory volume in one second (FEV1) expressed as percentage predicted (FEV1%), FEV1 forced vital capacity (FVC) ratio(FEV1/FVC) were assessed. 3] Differences between the groups in response to rehabilitation were identified using the unpaired Student's t test, while changes within groups were measured using the paired Student's t test.MAIN OUTCOME MEASURES: Respiratory muscular function, pulmonary function, arterial blood gas and 6-minute walking distance in two groups before and after intervention.RESULTS: All 60 chronic respiratory failure patients with stable chronic cor pulmonale were involved in-the analysis of results. Every parameters of blood gas and pulmonale function in two groups were similar before intervention (P ＞ 0.05). After 5-week intervention, PaO2, FEV1%, FEV1/FVC,PImax, PEmax, Pdimax and 6MWD were higher than before in treatment group and those in control group (P ＜ 0.05-0.01). PaCO2 after therapy was lower than before in treatment group and that in control group after treatment (P ＜ 0.01).CONCLUSION: Nocturnal NIPPV can markedly improve the arterial blood gas and pulmonary function, and increase respiratory muscle strength.