A multi-institutional experience of Micro-percutaneous Nephrolithotomy (MicroPERC) for renal stones: Results and feasibility of day case surgery.

ABSTRACT

PURPOSE: To report the multi-institutional outcomes of Microperc for nephrolithiasis and to assess its feasibility in outpatient care. METHODS: We retrospectively identified all adult patients who underwent Microperc for renal stones at three centres between May 2015 and March 2021. Interventions were performed by three Surgeons. One Surgeon adopted a "one-way" strategy and all Microperc were performed on an outpatient basis, while the other two Surgeons provided inpatient monitoring for at least one day after surgery. The primary endpoint was same-day discharge after Microperc without emergency department visits or unplanned readmission within 30 days of the procedure. The secondary endpoints included treatment outcomes and the 30-day complication rate. RESULTS: Out of 72 consecutive patients included, 32 patients (44.4%) had same-day discharge. Median Charlson score (1 [0-2]) and cumulative stone size (15 [12-20] mm) were comparable between both groups. At one month post procedure, 32 patients (44.4%) were stone free and 23 patients (32%) had residual micro-fragments<3mm, conferring an overall success rate of 76.4% (inpatient Microperc group 77.5% vs outpatient Microperc group 75%, P=1). Analysis of the 30-day complication rate showed similar results between the two groups (Clavien I-II 18.1%, Clavien≥III 4.1%). After outpatient care, the rate of immediate admission and unplanned readmission was 12.5% (n=4), mainly due to urinary tract infection. CONCLUSION: In this multi-institutional study, we report that outpatient Microperc is feasible in selected patients with no significant impact on postoperative outcome.