Modified amplatz sheath with suction versus standard sheath in percutaneous nephrolithotomy for treating large renal stones > 2 cm: a prospective randomized trial.

Objective: To evaluate the efficacy and safety of using a modified amplatz as an access sheath in percutaneous nephrolithotomy (PCNL) compared to the standard Amplatz sheath for the treatment of renal stones larger than 2 cm.

Methods: This prospective randomized study was conducted on 240 patients with renal stones larger than 2 cm who underwent PCNL. Patients were randomized into two equal groups: Group I (standard Amplatz sheath) and Group II (modified Amplatz sheath). Outcomes measured included operative time, stone-free rate (SFR), complications, and hospital stay.

Results: The modified Amplatz sheath group had a significantly shorter mean operative time compared to the standard sheath group (56 ± 12 vs. 83 ± 17 min, respectively; P < 0.001). The SFR was higher in the modified sheath group (90.8% vs. 80%; P = 0.017). Postoperative complications, such as fever (4.2% vs. 10.8%) and pain (13.3% vs. 20.8%), were significantly lower in the modified sheath group (P = 0.036). The modified sheath group also had a shorter hospital stay, with 93.3% discharged within two days compared to 85% in the standard group (P = 0.038). Multivariate analysis indicated that the use of the modified sheath reduced the risk of residual stones by 91% (OR = 0.086, 95% CI = 0.027-0.280, P < 0.001).

Conclusions: The use of a modified Amplatz sheath in PCNL significantly reduces operative time, increases the SFR, and decreases postoperative complications compared to the standard Amplatz sheath.