Modified supine percutaneous nephrolithotomy for large kidney and ureteral stones: technique and results

Background: Percutaneous nephrolithotomy (PCNL) is the standard treatment for kidney stones >2cm. Recently, a novel approach in the modified supine lithotomy position has been developed.

Objective: To demonstrate with a video our technique of supine PCNL (sPCNL) and present our experience.

Design, setting, and participants: From September 2009 to August 2010, 47 consecutive patients were prospectively evaluated. There were 31 single, 9 multiple, and 7 staghorn stones. The mean body mass index was 26.1±5 (range: 17.3-45.7), the mean stone size was 29.6±15.3mm (range: 10-75), and patients' American Society of Anesthesiologists scores were 1, 2, and 3 in 31, 11, and 5 cases, respectively.

Surgical procedure: Patients were positioned in Galdakao-modified supine Valdivia position. The details of the technique are shown in the film.

Measurements: Success was defined as patients free of stones or with residual stone fragments <4mm.

Results and limitations: Average operative room occupation time was 123.5±51.2min (range: 50-245). In the single, multiple, and staghorn stone groups, the immediate success rate after sPCNL was 90%, 78%, and 43%, respectively. Complications included one fever, two incidents of pyelonephritis, one renal colic, two urinary fistulae, one postoperative hemorrhage, and one incident of acute urinary retention. Mean hospital stay was 3.4±1.9 d (range: 2-12). Nine patients (19%) had a secondary procedure (extracorporeal shock wave lithotripsy or flexible ureterorenoscopy). At 3 mo, the success rate was 97%, 100%, and 100% in the single, multiple, and staghorn stone groups, respectively. However, the limitation of this study is its design, which is descriptive rather than comparative.

Conclusions: sPCNL is a safe and reproducible method. It offers the advantage of simultaneous retrograde and antegrade endoscopic combined intrarenal surgery, and we believe it is a further advancement in stone management. In addition, it is easier from the anesthetist point of view than the traditional prone approach. In our hands, it meant a simplification of the operative technique, resulting in a more time-efficient procedure.