Hospital-based analysis of trends and outcomes for patients undergoing pyelolithotomy

Objective: To determine trends in pyelolithotomy, evaluate risk factors for complications, and evaluate the difference in outcomes and charges between open and minimally invasive (MI) techniques. Patients and Methods: We used the Nationwide Inpatient Sample to identify patients with a diagnosis of having nephrolithiasis undergoing pyelolithotomy from 2008 to 2012. Total charges were inflation-adjusted to U.S. dollars in 2012. Patient demographics, hospital characteristics, and outcomes were reported and compared between open and MI groups after survey weighting. Results: We included a survey-weighted population of 17,294 patients, of whom 841 (4.9%) had MI pyelolithotomy. The proportion of MI cases increased by 2.57% annually (r² = 0.921, p = 0.01), although total pyelolithotomy cases remained stable. Simultaneous pyeloplasty occurred in 6.6% of all patients. Patients receiving open surgery experienced longer length of stay (3.9 days vs 2.7 days; p < 0.001), but accrued equivalent inflation-adjusted charges ($49,588 ± 2088 vs $51,716 ± 4893; p = 0.665). On multivariable analysis, higher Elixhauser comorbidity index and presence of any genitourinary anomaly were associated with experiencing a complication, while undergoing surgery at a top quartile hospital and elective admission status were protective against complications. MI technique and simultaneous ureteropelvic junction repair did not alter complication risk. Conclusion: While the annual number of pyelolithotomy cases was stable, there was an increasing trend toward MI technique. Both patient and hospital factors can significantly alter the risk for complications following pyelolithotomy.