Objective:To investigate the risk factors and their warning effectiveness for postoperative intestinal barrier dysfunction (IBD) in patients with severe traumatic brain injury (sTBI).Methods:A retrospective cohort study was conducted to analyze the clinical data of 101 patients with sTBI admitted to Wuxi Branch of Zhongda Hospital Affiliated to Southeast University from May 2020 to February 2023, including 63 males and 38 females, aged 21-81 years [(53.4±14.2)years]. All the patients underwent emergency surgery. The patients were divided into IBD group ( n=67) and non-IBD group ( n=34) according to whether or not they had IBD after surgery. The gender, age, basic diseases (hypertension and diabetes), types of intracranial hematoma (subdural, epidural, and intracerebral hematoma), preoperative Glasgow Coma Scale (GCS), cerebral hernia, intraoperative initial intracranial pressure (iICP), operation time, removal of bone flap, treatment time in ICU, initiation time of enteral nutrition, and use of broad-spectrum antibiotics were recorded in the two groups. Univariate and multivariate binary Logistic regression analyses were conducted to assess the correlations between above-mentioned indicators and incidence of postoperative IBD in sTBI patients and determine the independent risk factors for sTBI. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to evaluate the warning effectiveness of each risk factor for IBD. Results:The results of the univariate analysis showed that preoperative GCS, cerebral hernia, intraoperative iICP, removal of bone flap, treatment time in ICU, initiation time of enteral nutrition, and use of broad-spectrum antibiotics were significantly correlated with the incidence of IBD in sTBI patients ( P<0.05 or 0.01), while there were no correlations of IBD with gender, age, basic diseases, types of intracranial hematoma and operation time ( P>0.05). The results of the multivariate binary Logistic regression analysis showed that preoperative GCS≤5 points ( OR=2.49, 95% CI 1.17, 5.32, P<0.05), intraoperative iICP>23 mmHg (1 mmHg=0.133 kPa)( OR=1.20, 95% CI 1.03, 1.39, P<0.05), and initiation time of enteral nutrition>24 hours ( OR=10.03, 95% CI 1.26, 80.21, P<0.05) were highly correlated with postoperative IBD in sTBI patients. The results of the ROC curve analysis showed that intraoperative iICP had the highest warning value (AUC=0.91, 95% CI 0.85, 0.96), followed by preoperative GCS (AUC=0.88, 95% CI 0.82, 0.95), and initiation time of enteral nutrition had the lowest warning value (AUC=0.78, 95% CI 0.69, 0.87). Conclusions:Preoperative GCS≤5 points, intraoperative iICP>23 mmHg, and initiation time of enteral nutrition>24 hours are independent risk factors for postoperative IBD in sTBI patients. The warning value of intraoperative iICP ranks the highest for postoperative IBD in sTBI patients, followed by preoperative GCS, with initiation time of enteral nutrition having the lowest warning value.