F. A. Yamin1, L. Puckett1, A. Rios-Tovar2, B. R. Davis1 1Texas Tech University Health Sciences Center El Paso,Surgery,El Paso, TX, USA 2Methodist Hospital Dallas,Surgery,Dallas, TX, USA
Introduction: Optimal management of cholecystitis and elective gallstone disease is laparoscopic cholecystectomy. Underserved patients on the US- Mexico border undergo more frequent rates of conversion from laparoscopic to open cholecystectomy. Diagnostic staging criteria for acute cholecystitis are described in the Tokyo Guidelines (2007). This study delineates criteria to predict conversion risk for a wide range of gallbladder disease presentations in the Mexican-American population with low access to surgical care on the US-Mexico border.
Methods: This is a case-matched control study from University Medical Center of El Paso (July 2014- July 2015). Criteria include: demographics, ultrasound measurements, labs, and comorbidities. Multiple ranges are applied to individual variables and ranges were analyzed for statistical significance. Student’s t-test and Wilcoxon rank sum test assess the differences in risk factors for continuous variables. If they were categorical, the Fishers exact test, or chi-squared test was used to assess differences. The logistic regression model assessed likelihood of conversion. P values less than 5% were considered statistically significant. All analyses were performed using SAS V.9.4.
Results: Forty conversion to open and 275 laparoscopic cases were analyzed (male 79, female 208). Ethnicity included Hispanics (235) and Non-Hispanics (52). Elective surgery (132) and cholecystitis (155) were grouped. In an unadjusted model: WBC, total bilirubin, gender, ethnicity and gallbladder dimensions (wall thickness, length, and width) are significant risk factors for conversion. In the adjusted model, only white blood cell count, gender and ethnicity were significant. Odds of conversion in Hispanics are 10 times higher compared to Non – Hispanics. Odds of conversion for males are 3 times more likely. Odds of conversion are 7% more likely for each unit change in WBC. Conversions had an average WBC of 14,000 (max. 18,000, SD 4,000); total bilirubin average of 1.2 (max. 1.53, SD .28); gallbladder wall thickness average 3.30 cm ( SD 1.51), gallbladder length average 9.51 cm (max. 22.1, SD 4.36); and gallbladder width average is 3.79 cm (max. of 5.6, SD 1.31cm). Hospital length of stay and complications to include partial cholecystectomy and bile leak increased parallel with conversion rates.
Conclusion: Determination of preoperative factors that predispose to conversion from laparoscopic to open cholecystectomy allow for adjunctive treatment measures to include cholecystostomy and delayed operative intervention to reduce complications. Application of specific ranges smaller than the standard deviation would improve reliability of these predictors and demonstrate limitations of this study. This study expands known criteria for severity grading specific to the underserved population on the US-Mexico border. Further investigation creates improved power to predict the best course in complicated gallstone disease in the Mexican-American population with low access to expedient surgical care.