G. Molina1,2,3, B. Neville1, S. R. Lipsitz1, W. R. Berry1, A. B. Haynes1,2,3 1Ariadne Labs,Brigham And Women’s Hospital And The Harvard T.H. Chan School Of Public Health,Boston, MA, USA 2Massachusetts General Hospital,Department Of Surgery,Boston, MA, USA 3Harvard Medical School,Boston, MA, USA
Introduction: Laparoscopic cholecystectomy is increasingly being performed in the ambulatory setting, including hospital and freestanding ambulatory surgery centers (ASCs). Previous research has demonstrated the safety of ambulatory laparoscopic cholecystectomy in the elderly. These studies, however, did not distinguish between hospital and freestanding ASCs.
Methods: We used logistic regression, clustering by facility to evaluate if ambulatory setting (hospital ASC versus freestanding ASC) was an independent predictor of acute care (ED visits or inpatient admissions) within 1 and 7 days after a laparoscopic cholecystectomy among patients 65 years or older in South Carolina. Due to low number of events, we used a machine learning technique (supervised principal components regression) to adjust for all available patient characteristics (gender, race, insurance, median household income, and preoperative Charlson comorbidity index score). This technique is an alternative to using all variables when adjusting by generating one covariate from a combination of the original variables. This new covariate retains much of the original information as possible in a single covariate. A sensitivity analysis evaluating ASCs that performed at least 25 laparoscopic cholecystectomies annually among all adult patients was also performed in order to evaluate if these findings would persist after taking annual volume into account.
Results: There were 6,299 elderly patients who underwent a same-day laparoscopic cholecystectomy in the ambulatory setting in South Carolina from 2006 to 2013. Of these, 5,819 (92.4%) patients underwent a laparoscopic cholecystectomy at 58 hospital ASCs compared to 480 (7.6%) patients who underwent this operation at 16 freestanding ASCs. Elderly patients who had laparoscopic cholecystectomy performed at a freestanding ASC had a higher odds of being admitted to the hospital within 1 day when compared to hospital ASCs (Adjusted Odds Ratio (OR)=10.4, 95% Confidence Interval (CI) 3.9–27.5) but not within 7 days (OR=1.9, 95% CI 0.8–4.2). There was no significant difference between hospital ASCs and freestanding ASCs when evaluating subsequent ED visits (within 1 or 7 days). The sensitivity analysis confirmed these results.
Conclusion: Elderly patients who had same-day laparoscopic cholecystectomy at freestanding ASCs in South Carolina were more likely to be subsequently admitted to the hospital within 1 day when compared to hospital ASCs. As more surgical procedures are performed in the ambulatory setting, preoperative screening is critical to identify the safest and most efficient ambulatory surgery setting. Further research is needed on how to minimize acute care need following laparoscopic cholecystectomy at freestanding ASCs among the elderly.