[Clinical research about needle-tract assisted standard percutaneous nephrolithotomy for the treatment of complicated upper urinary tract calculi]

Objective: To investigate the safety and efficacy of needle-tract assisted standard percutaneous nephrolithotomy (PCNL) for the treatment of complicated upper urinary tract calculi. Methods: The clinical data of 1 562 patients with complicated upper urinary calculi who received standard PCNL from December 2013 to December 2017 at Department of Urology, the First Affiliated Hospital of Xiamen University were retrospectively analyzed. There were large residual stones in 256 patients through B-ultrasound exploration after standard PCNL, could't be detected with nephoscope in standard PCNL tracts. 16 F mini PCNL tract were established in 120 cases for treatment of residual stones, while needle-tract were established in order to guide nephroscope to find residual stones in 126 cases. Needle-tract were transferred to 16 F mini PCNL tract for treatment of residual stones in 10 patients if these residual stones could't be detected through needle-tract. Operation time, change of hemoglobin level after operation, incidence of postoperative complications, time of hospitalization and rate of stone clearance were measured in two groups. The statistical methods used included t test, Wilcoxon rank sum test, and χ² test. Results: There were 1 to 3 mini tracts (M(Q_R): 1(1)) established in the mini tracts group and 1 to 7 needle-tracts (M(Q_R): 3(2)) established in the needle-tract group (Z=-10.57, P=0.000). Compared with mini tract group, the operation time ((62.0±18.0) minutes vs. (84.0±15.5) minutes, t=10.242, P=0.000), hospitalization time ((4.40±0.86) days vs. (5.20±0.81) days, t=7.570, P=0.049), hemoglobin dropped ((1.31±0.47) g/L vs. (2.74±0.63) g/L, t=20.12, P=0.000), and incidence of postoperative complications (7.9% (10/126) vs. 19.2% (23/120), χ²=6.674, P=0.01) of needle-tract group were lower, while postoperative stone clearance rate was higher (89.7% vs. 76.7%, χ²=7.497, P=0.006). No perioperative severe complications such as pleural injury, pneumatothorax, perforation of renal, trauma of abdominal organ occurred in two groups. Conclusion: Needle-tract assisted standard PCNL for the treatment of complicated upper urinary calculi can significantly improve stone clearance rate, reduce operation time, decrease risk of kidney and surrounding organs damage.