ZIRK-Technique: Zero Ischemia Resection in the Kidney for High-Risk Renal Masses: Perioperative Outcome

Objectives: This study evaluates the feasibility and safety of open-partial nephrectomies in the ZIRK-technique (Zero Ischemia Resection in the Kidney) for renal masses with high-risk anatomical features - objectified by the PADUA score. Methods: We identified 40 consecutive cases of partial nephrectomies performed without clamping of the renal artery in our department of urology. Retrospective analysis of the preoperative CT or MRI scans showed 27 cases with a PADUA score ≥8, of which 15 cases had a score ≥10. Cases were in particular assessed regarding operation time (ORT), estimated blood loss (EBL), surgical margins and postoperative complications using the Clavien classification. Results: The mean age of the study population was 67.6 years with an average BMI of 26.8 kg/m2. The mean ORT was 1:46 with an average EBL of 521 ml. Clavien grade II complications were observed seven times, while 3 patients had a grade IIIa complication. Despite complex and adverse location of the tumors, nephron-sparing surgery without ischemia could be performed with negative surgical margins for all cases. EBL, transfusion rate and complication were considerably more frequent in high-risk tumors. Conclusion: Highly complex renal tumors, PADUA ≥10, can be resected in ZIRK-technique with good operative outcome and a low complication rate.