Emergency department and hospital revisits after ambulatory surgery for kidney stones: an analysis of the Healthcare Cost and Utilization Project

Our objective was to identify the rate of revisit to either emergency department (ED) or inpatient (IP) following surgical stone removal in the ambulatory setting, and to identify factors predictive of such revisits. To this end, the AHRQ HCUP ambulatory, IP, and ED databases for NY and FL from 2010 to 2014 were linked. Cases were selected by primary CPT for shock-wave lithotripsy (SWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PNL) with accompanying ICD-9 for nephrolithiasis. Cystoscopy (CYS) was selected as a comparison group. The risk of revisit was explored using multivariate models. The overall unplanned revisit rate following stone removal was 6.4% (4.2% ED and 2.2% IP). The unadjusted revisit rates for SWL, URS, and PNL are 5.9%, 6.8%, and 9.0%, respectively. The adjusted odds of revisit following SWL, URS, and PNL are 1.93, 2.25, and 2.70 times higher, respectively, than cystoscopy. The majority of revisits occurred within the first two weeks of the index procedure, and the most common reasons for revisit were due to pain or infection. Younger age, female sex, lower income, Medicare or Medicaid insurance, a higher number of chronic medical conditions, and hospital-owned surgery centers were all associated with an increased odds of any revisit. The most important conclusions were that ambulatory stone removal has a low rate of post-operative revisits to either the ED or IP, there is a higher risk of revisit following stone removal as compared to urological procedures that involve only the lower urinary tract, and demographic factors appear to have a moderate influence on the odds of revisit.