Evaluation of an intraoperative bleeding severity scale (VIBe scale) for use in HPB surgery

Abstract

Purpose: Bleeding is a major intraoperative complication for hepatic surgeons. Adjunct hemostats are used to achieve intraoperative hemostasis and may lead to improved surgical outcomes. However, clinical studies investigating these agents have not used standardized definitions for intraoperative bleeding, making it difficult to make comparisons. Validated Intraoperative Bleeding Scale (VIBe Scale) is one of the most promising scales to standardize intraoperative bleeding. It was validated with excellent concordance by multiple specialties including HPB, however representation of HPB surgeons in the analysis was low (Lewis KM et al. 2017). We describe a Spanish multicenter study for the evaluation of VIBe in HPB surgery. Method: All participants viewed and graded 14 bleeding videos and answered 14 questions to assess intra- and inter-observer concordance, usability, clarity, and relevance. Data of the HPB units and the clinical practice of participating surgeons was collected, with results analyzed depending on surgeon experience and volume of surgeries. A total of 47 surgeons from 10 HPB units participated in the study. Results: Participating hospitals performed 23±16 major and 56±24 minor hepatectomies per year. Minimally invasive surgery (MIS) was performed in a mean of 40.5% of the procedures. 63.3% of participating surgeons were male with a mean age of 41.6 years. 17% were unit/department heads and 83% were senior consultants. Mean experience was 9.3 years, and the majority were experts (21.3%) or advanced (53.2%) in MIS. Only 23.4% had previous knowledge of VIBe, but all surgeons used hemostats in their clinical practice. VIBe Scale achieved an average intra-observer concordance of 0.985 and inter-observer concordance of 0.929, neither were influenced by surgeon experience or volume of surgeries per year (Table). Mean grading for all videos was 67% correct, in line with the original validation. The majority of surgeons considered the scale represented the range of bleeding severity in their procedures (91%), relevant for evaluating intraoperative hemostasis in clinical studies (96%) and clinical practice (87.2%), useful in MIS (96%), and also to differentiate hemostatic agents (81%). Conclusion: VIBe Scale shows excellent concordance status among HPB surgeons to define intraoperative bleeding, with the majority agreeing that it was relevant for evaluating hemostasis and hemostatic agents, and could become a useful tool in clinical trials.Tabled 1Kendall’s coefficient of concordance (Kendall’s W)Concordance statusAverage Intra-observer agreementAll surgeons (N=47)0.985ExcellentAccording to surgeon experience High experience (N=23)0.990Excellent Low experience (N=24)0.981ExcellentAccording to number of surgeries per year High number (N=20)0.995Excellent Low number (N27)0.979ExcellentInter-observer agreementAll surgeons (N=47)0.929ExcellentAccording to surgeon experience High experience (N=23)0.941Excellent Low experience (N=24)0.922ExcellentAccording to number of surgeries per year High number (N=20)0.940Excellent Low number (N27)0.923ExcellentA Kendall's coefficient of 0.70 or greater was considered to be evidence of a scoring system with appreciable concordance, a coefficient of 0.80 or greater was considered to be good concordance, and a coefficient of 0.90 or greater was considered to be excellent concordance. Median experience was 7 years: low experience was considered ≤7 years; high experience was considered >7 years. Median number of surgeries per year was 35: low number of surgeries was considered ≤35 surgeries per year; high number of surgeries was considered >35 surgeries per year. Open table in a new tab A Kendall's coefficient of 0.70 or greater was considered to be evidence of a scoring system with appreciable concordance, a coefficient of 0.80 or greater was considered to be good concordance, and a coefficient of 0.90 or greater was considered to be excellent concordance. Median experience was 7 years: low experience was considered ≤7 years; high experience was considered >7 years. Median number of surgeries per year was 35: low number of surgeries was considered ≤35 surgeries per year; high number of surgeries was considered >35 surgeries per year.