A retrospective analysis on the effect of single-channel minimally invasive percutaneous nephrolithotomy combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions to treat complex kidney stones

BACKGROUND: Some types of complex kidney stones cannot be broken down and removed through single-channel percutaneous nephroscope or retrograde flexible ureteroscope. In order to be removed, these types of stones require multiple combined methods to be performed. The aim of this study was to retrospectively evaluate the clinical effect of single-channel minimally invasive percutaneous nephrolithotomy (mPCNL) combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions for treating complex renal calculi. METHODS: We selected 117 patients with complex renal calculi who were admitted to Peking University Shougang Hospital and Weifang People’s Hospital from January 1, 2017, to January 31, 2021. All patients were treated with single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions. During the operation, the patients were placed in a completely lateral decubitus position, or their lower limbs were placed in a semi-lithotomy position for a single attempt only. RESULTS: An 18-Fr percutaneous channel was successfully established in all patients. The mean operation time was 112±37 minutes, and the average blood loss was 71±31 mL. A 14-Fr renal fistula was maintained for 7 days, a urethral catheter for 2–3 days, and a ureteral stent tube for 2 weeks after each surgery. According to the results of computed tomography (CT) scans performed 3–5 days after the operation, the total lithotripsy success rate reached 100%, with a first-stage lithotripsy rate of 98.29%. Two patients were found to each have 1 residual stone, with a diameter of 4 mm, left in kidney by CT, which then was to be removed under local anesthesia. The average postoperative hospitalized time was 7±2 days, and no severe complications occurred perioperatively. CONCLUSIONS: Single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions is a safe, feasible, and highly effective method of treating complex renal calculi, which is of benefit to save operation time and facilitate operation process, because patient’s position could not need to be changed repeatedly during the surgery.