A comparison of cholecystitis grading scales

Area of Science:

• Gastroenterology and Hepatobiliary Surgery
• Surgical Outcomes Research
• Medical Device and Technology Evaluation

Background:

• The Parkland grading scale for cholecystitis (PGS) was previously developed to stratify gallbladder disease severity during laparoscopic cholecystectomy (LC).
• PGS demonstrated excellent interrater reliability and internal validation as an accurate measure of LC outcomes.
• This study compares PGS against the American Association for the Surgery of Trauma (AAST) score for predicting LC outcomes.

Purpose of the Study:

• To compare the predictive accuracy of the Parkland grading scale for cholecystitis (PGS) against the American Association for the Surgery of Trauma (AAST) score for laparoscopic cholecystectomy (LC) outcomes.
• To evaluate the reliability and predictive performance of PGS for operative difficulty, case length, conversion rates, and complications.
• To determine if a simpler, operative-based scale like PGS can effectively predict LC outcomes compared to a more complex, multi-input score.

Main Methods:

• Eleven acute care surgeons prospectively graded 179 gallbladders (GBs) using PGS and reported surgical difficulty.
• Three independent raters retrospectively graded GBs using PGS from stored images.
• Three additional surgeons assigned AAST scores; intraclass correlation coefficient assessed reliability for both scales, and regression models estimated perioperative outcomes.

Main Results:

• Parkland grading scale for cholecystitis (PGS) demonstrated superior prediction of operative difficulty (R=0.566 vs. 0.202), case length (R=0.217 vs. 0.037), open conversion rates (AUC=0.904 vs. 0.757), and complication rates (AUC=0.7039 vs. 0.6474) compared to AAST.
• Both PGS and AAST showed similar performance in predicting partial cholecystectomy, readmission, bile leak rates, and length of stay.
• Intraclass correlation coefficients were high for both scales (PGS: 0.8647, AAST: 0.8341).

Conclusions:

• Both the Parkland grading scale for cholecystitis (PGS) and the AAST score are accurate predictors of laparoscopic cholecystectomy (LC) outcomes.
• PGS is a superior predictor of operative difficulty, case length, open conversion rates, and complication rates.
• PGS offers an advantage due to its simplicity and ability to be scored intraoperatively at a single point in time.