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Prospective validation of the Parkland Grading Scale for Cholecystitis
Tarik D Madni1, Paul A Nakonezny2, Evan Barrios3
1UT Southwestern Department of Surgery, Dallas, TX, USA.
Background:
The Parkland Grading Scale for Cholecystitis (PGS) was developed as an intraoperative grading scale to stratify gallbladder (GB) disease severity during laparoscopic cholecystectomy (LC). We aimed to prospectively validate this scale as a measure of LC outcomes.
Methods:
Eleven surgeons took pictures of and prospectively graded the initial view of 317 GBs using PGS while performing LC (LIVE) between 9/2016 and 3/2017. Three independent surgeon raters retrospectively graded these saved GB images (STORED). The Intraclass Correlation Coefficient (ICC) statistic assessed rater reliability. Fisher's Exact, Jonckheere-Terpstra, or ANOVA tested association between peri-operative data and gallbladder grade.
Results:
ICC between LIVE and STORED PGS grades demonstrated excellent reliability (ICC = 0.8210). Diagnosis of acute cholecystitis, difficulty of surgery, incidence of partial and open cholecystectomy rates, pre-op WBC, length of operation, and bile leak rates all significantly increased with increasing grade.
Conclusions:
PGS is a highly reliable, simple, operative based scale that can accurately predict outcomes after LC. TABLE OF CONTENTS SUMMARY: The Parkland Grading Scale for Cholecystitis was found to be a reliable and accurate predictor of laparoscopic cholecystectomy outcomes. Diagnosis of acute cholecystitis, surgical difficulty, incidence of partial and open cholecystectomy rates, pre-op WBC, operation length, and bile leak rates all significantly increased with increasing grade.
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