Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy

Abstract

Background A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets. Methods Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall's tau for dichotomous variables, or Jonckheere-Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis. Results A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001). ConclusionWe have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty.

Perioperative outcomes after laparoscopic cholecystectomy in elderly patients: a systematic review and meta-analysis

“…For example, prospective scoring of patient frailty, an increasingly recognised feature associated with poor postoperative outcomes, is lacking [7,33]. Thirdly, a precise scoring of intraoperative cholecystectomy difficulty is lacking [34,35]. Elderly patients often have gallstones for many years and features of chronic cholecystitis with the obliteration of the tissue planes in Calot's triangle and even chronic fistulation, such as Mirizzi syndrome [36] or cholecysto-enteric fistulation, which naturally lead to poorer patient outcomes [37].…”

Achieving the critical view of safety in the difficult laparoscopic cholecystectomy: a prospective study of predictors of failure

“…The operative difficulty grade was based on the Nassar Scale [11] (Table 1). This scale was validated as a tool of reporting operative findings and technical difficulty in 2 different large datasets including the CholeS study and found to standardise the description of operative findings by multiple grades of surgeons in over 8800 cases [12].…”

3D laparoscopy does not reduce operative duration or errors in day-case laparoscopic cholecystectomy: a randomised controlled trial

“…Case difficulty could represent a major confounding variable within LC studies. We applied a four-point difficulty classification based on direct intraoperative visualisation recently validation in our population and saw a significant increase in operation time with each additional grade [22]. Although there were only 21 grade 3 and 9 grade 4 cases in the trial and there was a higher proportion of these within the 3D arm, 3D was significantly faster in these potentially challenging cases with a 40% operative time reduction.…”

“…Procedural difficulty varies and can influence surgical time and error rate [21]. Therefore, an intraoperative assessment of macroscopic gallbladder pathology was made using a validated scale: grade 1 (thin-walled gallbladder, no adhesions), grade 2 (filmy gallbladder adhesions), grade 3 (thick-walled or surrounded by adhesions) or grade 4 (dense adhesions, attachment of adjacent organs or gallbladder mucocele or empyema) [22].…”