Enhanced super-mini-PCNL (eSMP): low renal pelvic pressure and high stone removal efficiency in a prospective randomized controlled trial.

OBJECTIVE

In the present prospective randomized controlled trial (RCT), enhanced-SMP (eSMP) and conventional Chinese mini-PCNL (mPCNL) were compared to test the low renal pelvic pressure (RPP) and high stone removal efficiency in eSMP.

MATERIALS AND METHODS

Hundred patients with 2-5 cm renal calculus were enrolled. Renal pelvic pressure, operation time, lithotripsy time, removed stone volume, and complications were compared between eSMP and mPCNL statistically.

RESULTS

There was no significant difference in removed stone volume between mPCNL and eSMP (8.09 ± 3.36 vs. 7.88 ± 3.07 mm, t = 0.320, p = 0.750), lithotripsy time in mPCNL was longer than eSMP (49.6 ± 19.5 vs. 34.9 ± 14.2 min, t = 4.152, p < 0.001), thus stone removal efficiency was higher in eSMP (13.71 ± 1.18 vs. 9.82 ± 1.24 mm/h, t = 15.499, p < 0.001). Intra-operative RPP in mPCNL was higher than eSMP (17.72 ± 3.33 vs. 12.03 ± 2.37 mmHg, t = 9.524, p < 0.001); accumulated time of backflow status (RPP > 30 mmHg) in mPCNL was longer than eSMP (23.3 ± 16.9 vs. 3.7 ± 4.2 s, t = 7.710, p < 0.001). There was no significant difference in postoperative fever rate between mPCNL and eSMP (12.77% vs. 4.34%, χ = 2.095, p = 0.148), nor final stone-free rate (87.2% vs. 91.3%, χ = 0.401, p = 0.526). Hospital stay in eSMP was shorter than mPCNL (2.54 ± 0.72 vs. 3.00 ± 0.88, t = 2.724, p = 0.008).

CONCLUSION

Enhanced SMP (eSMP) was safe and effective in the management of 2-5 cm renal calculus. It can keep a lower renal pelvic pressure and a higher stone removal efficiency when compared to conventional Chinese mini-PCNL.

CLINICAL TRIAL REGISTRATION

NC03206515.