影响脑梗死后行机械通气患者撤机的危险因素分析

Influencing factors of ventilator weaning from patients with acute ischemic stroke

目的探讨影响脑梗死机械通气患者撤机的危险因素。方法需要机械通气的急性脑梗死患者38例,前瞻性观察机械通气前及撤机前的格拉斯哥昏迷量表(GCS)评分、生命体征、血液生化指标、浅快呼吸指数(RSBI)和血气分析等指标及其动态变化(用两者差值表示)。根据撤机后48 h是否需要重新应用呼吸机分为失败组(9例)和成功组(29例)。结果①38例患者中29例成功撤机,9例失败,撤机失败组平均年龄高于成功组,肺部感染和消化道出血的比例亦高于成功组,差异均具有统计学意义,P<0.01。②呼吸相关指标比较中,呼吸频率、RSBI和氧合指数等指标在成功组和失败组之间以及每组通气前和撤机前的比较中,差异均具有统计学意义,P<0.05。两组撤机前与通气前的差值比较中,PaCO_2、氧合指数和RSBI的差值比较具有统计学意义。③血常规和生化相关指标比较中,GCS评分、ALT等指标在成功组和失败组之间以及每组通气前和撤机前的比较中,差异均具有统计学意义,P<0.05。两组撤机前与通气前的差值比较中GCS、体温、血小板等的差值比较具有统计学意义。④多因素分析结果表明,与撤机相关的独立因素为机械通气前后RSBI和GCS的差值,两者联合预测撤机成功的敏感性为93.1%,特异性为66.7%,准确性为86.8%。结论动态监测脑梗死机械通气患者的意识状态和浅快呼吸指数有助于对撤机时机的把握。

Objective To evaluate the main influencing factors of ventilator weaning from patients with acute ischemic stroke. Methods Thirty-eight patients with acute ischemic stroke were mechanically ventilated in neuro-intensive care unit （N-ICU）. The Glasgow Coma Scale（GCS） ,traditional weaning predictors and rapid shallow breathing index （RSBI） before start and weaning of ventilation and their dynamic changes were collected and prospectively analyzed. Successful and failed weaning group were assured 48 hours after weaning. Results ① Of 38 patients, 29 patients were succeeded. The average age in the successful group was younger than that in the failed group. By univariate analysis, the rates of gastrointesti- nal hemorrhage and pulmonary infection were significantly higher than those in the failed group. ② There were significant differences in respiratory rate and RSBI between the two groups and between before weaning and before ventilation in each group. There were significant changes in PaCO2 , oxygen saturated index and RSBI between weaning and ventilation. ③ There were significant differences in GCS and ALT between the two groups or between before weaning and before ventilation. There were significant changes in GCS, tem- perature, ALT between weaning and ventilation. ④Logistic regression analysis with weaning outcome as the dependent variable, changes of RSBI and GCS before and after ventilation were the only significant variables in the model. By combining the two predictors, the sensitivity , specificity and accuracy were 93.1%, 66.7% ,and 86.8% respectively. Conclusion In the weaning process for patients with acute ischemic stroke, changes of RSBI and GCS before and after ventilation are the valuable and accurate predictors.