慢性阻塞性肺疾病患者呼吸机撤离指标的临床研究

Values as predictors of ventilator weaning for chronic obstructive pulmonary disease patients

目的探讨浅快呼吸指数(RVR)、气道闭合压(P0.1)和呼吸功(WOB)对慢性阻塞性肺疾病(COPD)机械通气患者撤机的指导意义。方法对准备撤机的60例COPD患者,在床旁监测呼吸频率(RR)、潮气量(VT)、每分钟通气量(MV)、最大吸气压(MIP)、气道闭合压(P0.1)、气道阻力(Raw)、顺应性(Cst)和自发性内源性呼气末正压(autoPEEP);比较常规撤机指标(RR、VT、MV、MIP)与RVR、P0.1、WOB对撤机的预测价值。结果撤机成功与失败的RVR为(61±23.1)bpm/L与(89±23)bpm/L,(P<0.05);撤机成功与失败的P0.1为(3.0±0.7)cmH2O与(4.9±0.8)cmH2O,(P<0.05);撤机成功与失败的WOB为(0.5±0.08)J/L与(0.61±0.15)J/L,(P<0.05)。以RVR≤100bpm/L为标准,预测撤机成功的正确率、灵敏度和特异度分别为90.0%、95.6%和75.0%;以P0.1≤5cmH2O为标准,预测撤机成功的正确率、灵敏度和特异度分别为86.7%、88.6%和62.5%,以WOB<0.75J/L为标准,预测撤机成功的正确率、灵敏度和特异度分别为85.0%、75.6%和62.0%。结论RVR、P0.1、WOB在预测撤机结果上优于常规撤机指标。

Objective To assess the values of rapid shallow breathing (RVR), airway occlusion pressure(P 0.1), and work of breathing(WOB) in predicting weaning of mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients. Methods Sixty COPD patients under consideration of weaning of mechanical ventilation underwent bedside measurement of respiratory rate (RR), tidal volume (VT), minute ventilation (MV), maximal respiratory pressure(MIP),airway occlusion pressure(P 0.1),airway resistance(Raw),static pulmonary compliance(Cst), and auto-positive end-expiratory pressure (auto-PEEP). RVR, P 0.1, and WOB were calculated. The predictive values for ventilator weaning of the conventional weaning predictors, RR, VT, MV, and MIP were compared with those of RVR, P 0.1, and WOB . Results The RVR of the patients with successful weaning was (61 ± 23.1) bpm/L, significantly lower than that of the patients with unsuccessful weaning 〔 (89 ± 23) bpm/L,P<0.05)〕.The P 0.1 of the patients with successful weaning was(3.0±0.7) cmH2O, significantly lower than that of those with unsuccessful weaning 〔(4.9±0.8) cmH2O P<0.05)〕. The WOB of the patients with successful weaning was (0.5±0.08) J/L, significantly lower than that of the patients with unsuccessful weaning〔(0.61±0.15 )J/L, P<0.05)〕. With RVR≤100 bpm/L set as criterion, the accuracy, sensitivity, and specificity of weaning success prediction were 90%, 95.6%, and 75% respectively. With P 0.1≤5 cmH2O set as criterion, the accuracy, sensitivity, and specificity of weaning success prediction were 86.7%, 88.6%, and 62.5% respectively. With WOB<0.75 J/L set as criterion, the accuracy, sensitivity, and specificity of weaning success prediction were 85% and 75.6%, and 62% respectively. Conclusion RVR, P 0.1, and WOB have a better predictive value as a weaning measure than the conventional predictors.