Association between the preoperative N-terminal pro-B-type natriuretic peptide and acute kidney injury in gastrointestinal surgery patients managed with enhanced recovery strategy: a retrospective cohort study

Importance Previous evidence has indicated that N-terminal pro-B-type natriuretic peptide (NT-proBNP) is associated with postoperative acute kidney injury (AKI). However, the association between preoperative NT-proBNP level and postoperative AKI in surgeries managed with enhanced recovery after surgery (ERAS) strategy requires further clarification. Objective To explore the association between preoperative NT-proBNP and the incidence of postoperative AKI in patients who underwent gastrointestinal surgeries and managed with ERAS strategy. Design A retrospective cohort study. Setting A review of documented cases of elective gastrointestinal surgeries managed with ERAS strategy occurred at Xijing Hospital from 01 May 2017 to 30 June 2022. Participants A total of 629 patients aged 18 years or older who were scheduled for elective gastrointestinal surgeries and subjected to the ERAS strategy with preoperative NT-proBNP and creatinine measurements were included in the analysis. Exposure Preoperative serum concentrations of NT-proBNP. Main outcomes and measures The primary outcome was the incidence of postoperative AKI. Preoperative NT-proBNP was divided into high- or low-level groups based on the median (165 pg/ml). Logistic regression was used to explore the association between increased preoperative NT-proBNP level and risk of AKI. Results After screening 1932 case records, 629 cases were included in the final analyses. The average age was 63.5 (15.3) years old and 197 (31.3%) of them were female. Among them, 112 (17.8%) developed postoperative AKI. The incidence of AKI was 21% in the high NT-proBNP group, and 14.6% in the low NT-proBNP group. Patients with higher preoperative NT-proBNP levels (≥ 165 pg/mL) have significant higher risk of postoperative AKI as compared to those in the lower group (adjusted OR 1.75; 95% CI 1.12 to 2.73). Conclusions and relevance Increased preoperative NT-proBNP is associated with an elevated risk of postoperative AKI in patients who underwent gastrointestinal surgery and managed with ERAS strategy. Trial registry number Clinical trial registry number: NCT06145347 NT-proBNP is associated with postoperative AKI. The implementation of ERAS may be associated with increased risk of postoperative AKI. In this cohort analysis of 629 patients, 17.8% developed postoperative AKI. Increased total volume infusion significantly mediated 15.5% of NT-proBNP-associated elevated AKI risk in this study. Increased preoperative NT-proBNP is associated with an elevated risk of postoperative AKI in patients who underwent gastrointestinal surgery and managed with ERAS strategy.