Risk stratification in laparoscopic liver resections: a review of available scales and validation with a Bulgarian cohort of patients

Introduction: Laparoscopic liver surgery underwent tremendous development during the past decade. The increased technical complexity of this procedure implies a gradual increase in surgical difficulty, relative to the surgeon’s experience. Various difficulty scoring systems (DSS) have been developed to facilitate patient selection for laparoscopic hepatectomy. Methods: We performed an analysis of a prospectively maintained database for the period January 2019 – January 2022. We identified patients, who underwent laparoscopic hepatectomy. They were staged according to the four DSS: Iwate, Institut Mutualiste Montsouris (IMM), Southampton and Hasegawa. We compared the results between the difficulty levels with the actual intraoperative parameters (Pringle-maneuver time, blood loss, hemotransfusion rate and operative time) and postoperative results. The data was evaluated using Jonckheere-Terpspa trend analysis and AUROC analysis. The correlation was assessed using Spearman’s rho. Results: We identified 60 patients, satisfying the inclusion criteria. The mean age of the group was 60 years, with 43% being male. The analysis confirmed the positive correlation between the four DSS and the intraoperative parameters. The risk of conversion or adverse postoperative outcome could not be adequately predicted by either of the DSS. Regarding the conversion risk, the IMM scale has the best discriminative ability (AUC=0,597), while the Hasegawa scale has the best ability to predict postoperative complications (AUC=0,612). Conclusions: We validated the four DSS for the Bulgarian population. From a practical standpoint, the IMM scale is most convenient for application during routine surgical practice.