A prospective cohort study - comparative analysis of liver enzyme and other biochemical blood markers 24 hours after laparoscopic surgery with and without liver retractor use

Introduction. Laparoscopic gastric surgery offers numerous advantages over open procedures but is associated with transient liver enzyme elevations (TLEE), particularly in cases involving liver retraction. Nathanson liver retractor (NLR) is commonly used in gastric surgeries to improve surgical exposure but may contribute to TLEE. Aim: To evaluate the impact of liver retractor use during laparoscopic gastric surgeries on liver enzyme tests and other biochemical blood markers and assess its clinical significance. Methods. A prospective cohort study was conducted including 119 patients undergoing elective laparoscopic surgeries at the Lithuanian University of Health Sciences Hospital Kaunas Clinics between June and November 2024. Patients were divided into two groups: the retractor group (n=59; fundoplication or gastric resection) and the control group (n=60; cholecystectomy). Laboratory parameters were assessed preoperatively, immediately postoperatively, and on the first postoperative day. Statistical analysis included ANCOVA, logistic regression, and ROC curve analysis. Results. ALT and AST levels were significantly elevated postoperatively in the retractor group (p75 min and >95 min were predictive of ALT and AST elevations, respectively. CRP and LDH levels were significantly higher in the retractor group (p<0.001). Surgery duration >75 min and >95 min were predictive of ALT and AST elevations, respectively. CRP and LDH levels were significantly higher in the retractor group (p<0.001 and p=0.007), while bilirubin, coagulation and renal markers showed less pronounced differences. ROC analysis identified surgery duration as a moderate predictor of AST elevation (AUC=0.683). Conclusion. Liver retraction during laparoscopic gastric surgery is associated with transient elevations in liver enzymes and inflammatory markers, particularly in prolonged procedures. These findings emphasize the importance of perioperative monitoring and highlight the need for further research on long-term hepatic outcomes.