Ambulatory Percutaneous Nephrolithotomy in a Free-Standing Surgery Center: An Analysis of 500 Consecutive Cases

Percutaneous nephrolithotomy (PCNL) is an effective procedure for removal of large kidney stones; however, PCNL has traditionally been reserved for inpatient surgery. Certain cases are being performed entirely at an ambulatory surgery center (ASC), known as ambulatory PCNL (aPCNL). Five hundred consecutive PCNL procedures performed at a free-standing ASC between April 2015 and February 2019 were analyzed. Patient demographics, stone characteristics, operative characteristics, and postoperative data, including transfer to hospitals, 30-day readmissions, and complications > Clavien I, were recorded. The mean age of patients undergoing PCNL at the ASC was 57 (range: 16-86) and body mass index 30 (16-49). American Society of Anesthesiologists (ASA) compositions are as follows: ASA 1 (6.5%), ASA 2 (56.2%), ASA 3 (37.2%), and ASA 4 (0. 1%). The mean stone burden was 30 mm (5-140). Standard tract dilation (24-30F) comprised 77% of cases. Ninety-two percent of cases were performed with a single tract, and 99% of cases had a ureteral stent as the only form of drainage (tubeless PCNL). The mean operative time was 104 minutes (32-305), and postanesthesia care unit time was 97 minutes (37-247). The predicted stone-free rate was 84%. Twelve patients (2.4%) required transfer to hospital, and the 30-day readmission rate was 4.2%. aPCNL is a safe and feasible procedure if performed by a high volume endourologist, even within the confines of a free-standing ASC. It is our opinion that the utilization of endoscopic combined intrarenal surgery facilitates high stone-free rates with minimal morbidity and low readmission rates. The institutional review board number is WIRB # 20171472.