ICU老年机械通气患者呼气末正压与喂养不耐受的相关性

Correlation between positive end-expiratory airway pressure and enteral nutritional intolerance in elderly patients in ICU with mechanical ventilation

目的探讨呼气末气道正压(PEEP)与ICU老年患者肠内营养不耐受(FI)的相关性,为临床肠内营养治疗提供参考。方法选取行气管插管机械通气治疗的80例老年患者作为研究对象,于肠内营养(EN)前及EN后连续7 d测量腹内压(IAP),评估患者EN过程中FI(腹泻、便秘、呕吐/返流、胃肠道出血)发生情况,采用偏相关分析PEEP与IAP的相关性、IAP与FI的相关性,确定PEEP预测FI的最佳临界值和IAP预测FI的最佳临界值。结果研究对象的IAP基线水平较低,以0级为主,没有Ⅱ级及以上者。EN开始后7 d内IAP的平均水平以0级和Ⅰ级为主,Ⅱ级和Ⅲ级腹内压频数明显增多,无Ⅳ级腹内压。患者腹内压基线水平与EN后7 d内腹内压平均水平比较,差异有统计学意义(P<0.05)。FI发生率为72.5%,FI主要表现为腹泻(40%)。相关分析显示PEEP与IAP呈正相关(P<0.05),PEEP判断FI的受试者工作特征(ROC)曲线下面积(AUC)为0.94(95%CI:0.869~1.0),其预测FI的最佳临界点为3.0 cmH2O。IAP基线水平和EN 7 d IAP均值预测FI的AUC分别为0.929(95%CI:0.835~1.0)和0.995(95%CI:0.982~1.0),其预测FI的最佳临界点分别为7.75 mmHg(1 mmHg=0.133 kPa)和11.05 mmHg。结论PEEP与ICU老年机械通气患者FI呈正相关,IAP与FI呈正相关,当PEEP≥3 cmH2O、IAP基线水平≥7.75 mmHg、EN 7 d IAP≥11.05 mmHg时,要警惕FI的发生。

Objective To investigate the correlation between feeding intolerance(FI)of enteral nutrition(EN)and positive end-expiratory airway pressure(PEEP)in elderly patients who got medical treatment in intensive care unit(ICU)with mechanical ventilation.Methods In this study,80 elderly patients with mechanical ventilation in the ICU ward of our hospital were selected to measure intral-abdominal pressure(IAP)before the start of EN and during the first 7 days of EN.The incidences of FI during the first 7 days were recorded.Results The incidence of FI of the patients was 72.5%,and the most common symptoms is diarrhea(40%).Partial correlation analysis shows that PEEP was positively correlated with IAP(P<0.05).The AUC under the ROC curve of the PEEP judges FI was 0.94(95%CI:0.869-1.0),and the best threshold for predicting FI was 3.0.The AUC under the ROC curve of the IAP baseline level and the first 7 days IAP mean prediction FI were 0.929(95%CI:0.835-1.0)and 0.995(95%CI:0.982-1.0),respectively;with the best thresholds for predicting FI were 7.75 mmmHg and 11.05 mmHg,respectively.Conclusion Elderly patients in ICU mechanical ventilation with PEEP face high incidence of FI.PEEP and FI are correlated.IAP and FI are correlated.PEEP and the baseline IAP and the average of IAP during the first 7 days of EN could predict the occurrence of FI.