Risk Factors For Prolonged Mechanical Ventilation In Patients With Open Abdominal Surgery

Objectives To identify the risk factors of prolonged mechanical ventilation following open abdominal surgery.Methods From October 2015 to October 2016,152 mechanically ventilated patients admitted into the intensive care unit(ICU)following open abdominal surgery in North China University of Science and Technology affiliated hospital.These included patients(86 man,66 women,mean age: 67.74±16.00 years)were divided into 2 groups according to the duration of mechanical ventilation,those who were tracheally extubated within 24 h after admission to the ICU(n=106)and those who required mechanical ventilation for more than 24 h(n=46).To identify the independent predictors for prolonged mechanical ventilation,we compared preoperative factors and intra or postoperative factors between the 2 groups.ICU mortality and postoperative complications,length of the ICU and hospital stays were compared between the 2 groups.Hospital outcome variables were obtained from patients’ medical records.Multivariate stepwise forward logistic regression analysis was used to identify independent risk factors for prolonged mechanical ventilation.Each variable that was shown to be significant(P < 0.1)by univariate analysis was examined by multivariate analysis.Results With univariate analysis,significant differences were found in the following variables: emergency surgery,shock and WBC count in the preoperation,red blood cell and plasma transfusion volume,the total fluid volume in the intraoperation,24-h fluid volume,WBC count,ALB level,oxygenation index,APACHEⅡscore in postoperation(P﹤0.05).Multivariate analysis showed that emergency operation(P=0.014),preoperative WBC count(P=0.018),postoperative oxygenation index(P=0.024),and postoperative APACHEⅡ score(P=0.035)were independent predictors of prolonged mechanical ventilation.There was significantly longer in ICU(P<0.001)and hospital stay(P=0.029),but no significant difference in ICU mortality(P=0.493)and postoperative complications(P=0.286).Conclusions Emergency operation,preoperative WBC count,postoperative oxygenation index and postoperative APACHEⅡ score increase the risk for prolonged mechanical ventilation in open abdominal surgerical patients.