Readmission to surgical intensive care unit after hepatobiliary-pancreatic surgery: risk factors and prediction

Objective To find the pathogenies and risk factors related to surgical intensive care unit (SICU) readmission for patients who underwent hepatobiliary-pancreatic surgery, and to develop a predictive model for determining patients who are likely to be readmitted to SICU. Methods The patients who admitted to SICU of the Affiliated Hospital of Qingdao University from January 2013 to August 2018; who first stayed in SICU after hepatobiliary-pancreatic surgery; who were assessed and discharged from SICU by surgeons and SICU physicians after treatment, and then transferred to SICU again because of the change of their condition were enrolled. The unintended return to SICU within 3 days and 7 days were recorded. Patients who returned to SICU within 7 days were studied for the pathogenies, risk factors and predictive model of returning to SICU, and non-returning patients were enrolled according to 1∶1 as the controls. A total of 43 indicators were divided into five categories, including general clinical data, medical history, surgical indicators before first admission of SICU, length of first SICU stay, and other indicators on the day of first discharge from the SICU. Logistic regression was used to screen the risk factors associated with SICU readmission, then the Nomogram diagram was drawn by using the R 3.4.1 software for predicting SICU readmission, and the classification performance of Nomogram was evaluated by self-help sampling test. Results Of the 763 patients discharged from the SICU, 2.10% (16/763) of them were readmitted within 3 days and 3.28% (25/763) were readmitted within 7 days to the SICU unexpectedly. The pathogenies of SICU readmission within 7 days included infection [56.00% (14/25)], heart failure [16.00% (4/25)], infarction [12.00% (3/25)], bleeding [12.00% (3/25)], and sutures splitting [4.00% (1/25)]. The pathogenies of SICU readmission within 3 days included infection [56.25% (9/16)], heart failure [18.75% (3/16)], infarction [12.50% (2/16)], and bleeding [12.50% (2/16)]. Nomogram analysis showed that the risk factors associated with unplanned SICU readmission were length of first SICU stay, history of hypertension, and activity of daily living (ADL) score, white blood cell count (WBC), arterial partial pressure of oxygen (PaO2), prothrombin time (PT), fibrinogen (FIB) on the day of first SICU discharge. Self-help sampling test was carried out on the Nomogram map, and the results showed that the coherence index (C-index) was 0.962 [95% confidence interval (95%CI) = 0.869-1.057]. The classification performance of the model was good. Conclusions The common pathogenies of SICU readmission for patients who underwent hepatobiliary-pancreatic surgery were infection, heart failure, infarction and bleeding. Risk factors of readmission after SICU discharge included the length of first SICU stay, history of hypertension, and ADL score, WBC, PaO2, PT, FIB on the day of first SICU discharge. The model consisted of above risk factors showed a good performance in predicting the probability of readmission after SICU discharge for patients who underwent hepatobiliary-pancreatic surgery. Key words: Hepatobiliary-pancreatic surgery; Intensive care unit; Readmission; Risk factor; Prediction model