变异性压力支持通气在慢性阻塞性肺疾病急性加重合并呼吸衰竭中的短期应用观察

摘要

目的 探讨变异性压力支持通气(Noisy PSV)在慢性阻塞性肺疾病急性加重(AECOPD)合并呼吸衰竭患者中短期应用的可行性及安全性,为确立AECOPD新的脱机模式提供基础支持.方法 进行单中心、前瞻性、随机、交叉临床研究.收集天津市海河医院2014年11月-2015年10月入住重症监护病房(ICU)、有创机械通气>24 h的AECOPD合并呼吸衰竭患者46例,经常规治疗病情好转,在自主呼吸恢复阶段随机顺序给予常规压力支持通气(PSV)和Noisy PSV各2 h.2种模式下压力支持(PS)水平以能维持约8 mL/kg的潮气量(Vt)为准,呼气末正压(PEEP)和吸氧浓度维持之前水平;Noisy PSV模式下PS的变异率设定为30%.比较2种模式下气体交换、血流动力学、肺功能参数、呼吸方式及人机同步性等指标.结果 所有患者均能耐受2种通气模式,未见明显的不良反应.2种通气模式下气体交换、血流动力学、呼吸力学等指标的变化均在临床可接受的范围.与PSV相比,Noisy PSV模式下Vt的变异性明显增加,人机不同步发生次数明显减少.结论 Noisy PSV通气模式在AECOPD呼吸衰竭患者自主呼吸阶段应用是安全、可行的,并且在Vt变异性及人机协调性上有一定优势,有望成为AECOPD脱机的新模式.%Objective To investigate the effects of noisy pressure support ventilation (Noisy PSV) in patients of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with respiratory failure, and to provide basic support for the new weaning mode for AECOPD. Methods A single-center, prospective, randomized, crossover clinical research was conducted. A total of forty-six AECOPD combined with respiratory failure patients who mechanically ventilated more than 24 hours in intensive care unit (ICU) of Tianjin Haihe Hospital from November 2014 to October 2015 were enrolled in this study. When the respiratory failure improved through conventional treatment, patients were mechanically ventilated with conventional PSV and Noisy PSV for two hours respectively in random sequence during spontaneous breathing recovery phase. The pressure support (PS) level was titrated to reach tidal volumes (Vt) about 8 mL/kg in both modes. The level of positive end-expiratory pressure (PEEP) and fraction of inspired oxygen were kept unchanged in both modes. The coefficient of variation of PS during Noisy PSV was set at 30%. Data of gas exchange, hemodynamics, lung functional parameters, breathing patterns and patient-ventilator synchrony were analyzed. Results All of the patients were well tolerated with the two modes, and no adverse reactions were found. The changes of gas exchange, hemodynamics, respiratory mechanics in PSV and Noisy PSV showed a clinical acceptable range. The variability of Vt was significantly increased in Noisy PSV mode than that in conventional PSV mode. While the number of asynchrony events was decreased in Noisy PSV mode than that in conventional PSV mode. Conclusion The Noisy PSV is safe and feasible for patients of AECOPD with respiratory failure, which may be a new weaning mode for AECOPD.