#0783

Propensity Score Matching of Suction vs non-suction Mini Percutaneous Nephrolithotomy (mPCNL) 30 day outcomes from a real world multicentre prospective study. An EAU Endourology and AUSET Collaboration

X. Pek¹, S. Yuen², D. Castellani³, J. Kalathia⁴, K. Fong⁵, B. Somani⁶, T. Herrmann⁷, V. Gauhar⁸, S. Registry⁹

¹Ng Teng Fong General Hospital, Singapore, Singapore
²S. H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China, Hong Kong, Hong Kong, China
³Urology Unit, Azienda Ospedaliero-Universitaria Ospedali Riuniti Di Ancona, Via Conca 71, 60126, Ancona, Italy, Ancona, Italy
⁴Fortune Urology Clinic, Botad, Gujarat, India, Gujarat, India
⁵Department of General Surgery, Singapore General Hospital, Singapore, Singapore
⁶Department of Urology, University Hospitals Southampton, NHS Trust, Southampton, UK., Southampton, United Kingdom
⁷Department of Urology, Spital Thurgau AG, Kantonsspital Frauenfeld, Pfaffenholzstrasse 4, CH 8501, Frauenfeld, Switzerland. Division of Urology, Department of Surgical Sciences, Stellenbosch University, Western Cape, South Africa. Hannover Medical School, Hannover, Germany, Hannover, Germany
⁸Ng Teng Fong General Hospital, Singapore, Singapore, Singapore
⁹Asian Institute of Nephrology and Urology, Chennai, Chennai, India

Introduction:

Mini percutaneous nephrolithotomy (mPCNL) has equivalent stone free rates (SFR) compared with standard PCNL. The latest EAU guidelines suggest that there is evidence for using suction as a complementary tool during mPCNL. We report 30 day perioperative outcomes between suction (smPCNL) and non-suction mPCNL.

Material and methods:

This was a prospective, multicentre, investigator-initiated study by 20 surgeons from 14 countries who performed both smPCNL and non-suction mPCNL from January to December 2024. The primary outcome was to assess complete stone free status (Grade A) on a 30-day CT scan. Optimal propensity score matching (PSM) covariate was achieved with absolute standardized mean difference (ASMD) < 0.1 at a caliper width of 0.004. Outcomes were analyzed using either T-test or Mann-Whitney U test. Categorical data between groups were analyzed using Chi-squared test.

Results:

Of 1915 patients (1534 smPCNL, 381 non-suction), PSM yielded 664 smPCNL and 309 non-suction patients. Baseline characteristics and stone characteristics including Guy's stone score, Hounsfield units, largest stone diameter and stone location were well matched. Both groups showed high 30-day 100% SFR (i.e Grade A) (85% vs 87%, OR 0.9 [CI 0.59-1.37], p=0.637). SmPCNL group had shorter operative time (42 vs 57mins, p<0.001), high intraoperative SFR determined by visual inspection or fluoroscopy (82.6% vs 69.6%, p<0.001) and lower blood transfusion rates (1.4 vs 3.6%, p=0.044). Infectious complications did not differ. On multivariate analysis, stone volume (OR 0.93, 95% CI [0.89; 0.97], p=0.002), fluoroscopy associated with ultrasound guided access (OR=0.44, 95%CI [0.26; 0.73], p=0.002) and sheath size <20 Fr (OR=0.4, 95% CI [0.21; 0.74], p=0.004) were factors significantly associated with lower odds of Grade A SFR.