MP69-11 ENHANCED SUPER-MINI-PCNL(ESMP) TECHNOLOGY: BOTH IN LOW RENAL PELVIC PRESSURE AND HIGH EFFECTIVENESS FOR STONE CLEARANCE

Abstract

INTRODUCTION AND OBJECTIVE: Super mini-PCNL (SMP) technique has developed rapidly and matured gradually in recent years. However, 14Fr ultra micro channel in SMP would prolong operation time when dealing with the large burden stone, and potentially increase renal pelvic pressure and bring postoperative fever. We enlarged the suction sheath to 18 Fr on the basis of SMP, and actively sucked out stone fragments and perfusion fluid during lithotripsy in order to improve lithotripsy efficiency and maintain low intrarenal pelvic pressure, which was named enhanced-SMP(eSMP). This study was aimed to compare the safety and efficacy of eSMP and mini-PCNL (mPCNL) in the treatment of renal calculi larger than 2.5cm. METHODS: 110 patients with renal calculi were treated with PCNL and randomly divided into eSMP group and mPCNL group. Ultrasound combined with X-ray puncture and 18Fr percutaneous nephrolithotomy were performed in eSMP group, peel-away sheath in mPCNL group, and holmium laser combined with pneumatic lithotripsy under ureteroscope (11Fr) and 8/9.8Fr respectively. Intraoperative intra-pelvic pressure was monitored by using an invasive arterial pressure measurement system to connect a retrograde ureteral catheter inserted into the pelvis. The basic data of patients, operation time, lithotripsy time, stone volume and other related indicators were collected, and the postoperative complications were observed and statistically analyzed. RESULTS: There was no significant difference in preoperative parameters between the two groups, such as age (40.1 + 17.7 vs. 44.2 + 21.1 y, P = 0.102), BMI (24.1 + 6.5 vs. 23.5 + 7.3 kg / m2, P = 0.753), stone size (4.1 + 0.7 vs. 4.3 + 0.9 cm, P = 0.945) (p > 0.05). The basal intrapelvic pressure in eSMP and mPCNL groups was 13.0 (+ 3.2) and 12.1 (+ 2.9) mmHg, respectively, with no statistical difference (p = 0.504), while the intraoperative intrapelvic pressure in eSMP group was decreased (13.0 (+ 3.2 vs. 9.5 (+ 3.6) mmHg), while the intraoperative intrapelvic pressure in mPCNL group was increased (12.1 (+ 2.9 vs. 16.5 (+ 4.4) mmHg), but there was no statistical difference (p > 0.05). It was lower than mPCNL group (9.5 + 3.6 vs.16.5 + 4.4mmHg, p=0.023). The operation time in eSMP group was shorter than that in mPCNL group (58.6 There was no statistical difference in stone volume between the two groups (12.8 (+ 5.2) vs. 12.0 (+ 6.3) ml, P = 0.768), but the removal of stone volume by metal negative pressure suction sheath group was superior to that by peel-away sheath group (0.240 (+ 0.017 vs. 0.159 (+ 0.022) ml/min, P = 0.041). There was no significant difference between the two groups in terms of postoperative hemoglobin decrease (11.6 (+ 5.4 vs. 9.1 (+ 4.7 g / L, P = 0.873), postoperative fever rate (2/55 vs. 5/55, P = 0.438), postoperative stone clearance rate (50/55 vs. 47/55, P = 0.376) and hospital stay (2.9 (+ 0.5 vs. 3.1 (+ 0.4 d, P = 0.796). CONCLUSIONS: Enhanced SMP can accelerate lithotripsy efficiency and maintain low intrapelvic pressure compared with traditional mPCNL by suction sheath perfusion. ESMP is safe and effective in the treatment of kidney stones over 2.5 cm. It can be used to treat kidney stones with a greater load of 18 Fr channels than SMP. (Figure Presented).