自主呼吸试验在机械通气脱机过程中的应用

目的 自主呼吸试验(SBT)作为程序化拔管步骤在机械通气脱机过程中的应用.方法 程序化拔管患者行前瞻性研究,非程序化拔管患者行回顾性分析,比较两组机械通气时间、呼吸机相关性肺炎(VAP)发生率、48 h复插管率、住ICU天数及ICU病死率.对于程序化拔管组患者,比较SBT成功与SBT失败、拔管成功与拔管失败组SBT前后监测指标的变化.结果 程序化拔管组较非程序化拔管组机械通气小时数(经Ln数据转换后)缩短(4.01±0.71 vs 4.51±0.85,P<0.05).住ICU天数(经Ln数据转换后)缩短(1.86±0.82 vs 2±48±0.92±P<0.05),VAP发生率及48 h复插管率差异无统计学意义.程序化拔管组SBT成功与SBT失败患者SBT前后心率、呼吸频率、浅快呼吸指数(f/Vt)、PaC_2的变化差异有统计学意义;而拔管成功与拔管失败患者SBT前后监测指标的变化差异无统计学意义.5例拔管失败患者中3例由于痰液引流障碍导致48 h内复插管.结论 程序化拔管可缩短机械通气时间.减少住ICU天数,不增加48 h复插管率.SBT前后心率、呼吸频率、f/Vt、PaCO_2变化对于判断SBT是否成功较其他指标更为重要.对于拔管后可能存在痰液引流障碍的患者需谨慎拔除气管插管.

Efficacy of spontaneous breathing trial in process of weaning and extubation

Objective To evaluate the efficacy of spontaneous breathing trial(SBT) as a step of protocols-directed weaning and extubation.Methods Protocols-directed weaning and extubation were studIed prospectively and no-protocols-directed weaning and extubation were evaluated retrospectively.Duration of ventilation,the incidence of ventilator-associated pneumonia(VAP),intubation rate within 48hours,duration of ICU,mortality in ICU were compared between two groups.As for protocols-directed weaning and extubation group,the variations of monitoring index before and after SBT corresponding to SBT success and SBT failure groups,as well as extubation success and extubation failure groups,were compared.Results Duration of ventilation hours and duration of ICU days(data tranformed by Ln)were shorter in protocols-directed weaning and extuhation group than those in no-protocols-directed weaning and extubation group(4.01±0.71 vs 4.51±0.85;1.86±0.82 vs 2.48±0.92,P<0.05).The incidence of VAP and intubation rate within 48 hours were no significant difference between two groups.The change of heart rate,respiratory rate,rapid shallow breathing index(f/Vt)and PaCO_2 were significantly different between SBT success and SBT failure groups.Those parameters had no significance between extubation success and extubation failure groups.Among 5 extubation failure patients,3 patients were intubation because of sputum drainage failure.Conclusions Protocols-directed weaning and extuhation shorten the time of mechanical ventilation and average ICU stay time,while the intubation rate was not increased.The change of heart rate,respiratory rate,f/Vt and PaCO_2 were more important to judge the SBT result.To patients with excessive mucinoid sputum and without effective drainage,the extubation should be eonducted prudentiy.