Diabetes, multiple-tract procedures, prolonged operative time, and the occurrence of intraoperative complications are associated with significantly increased blood loss. Atrophic parenchyma and past ipsilateral intervention are associated with reduced blood loss. On the basis of this evidence, maneuvers that may reduce blood loss and transfusion rate include ultrasound-guided access, use of Amplatz or balloon dilatation systems, reducing the operative time, and staging the procedure in cases of a large stone burden or intraoperative complications. Reducing the tract size in pediatric cases, nonhydronephrotic systems and those with a narrow infundibulum, and secondary tracts in a multiple-tract procedure may also reduce blood loss during PCNL.

Tubeless PCNL is associated with the least postoperative pain, urinary leakage and hospital stay. Small bore nephrostomy drainage may be a reasonable option in patients in whom the incidence of stent dysuria is likely to be higher.

Monotherapy with PCNL is safe and effective in the management of staghorn and complex renal calculi in single hospital stay. Ultrasound-guided peripheral caliceal puncture and limiting the tract dilatation to 22F are important factors in reducing the blood loss. Multiple tracts increase the hemoglobin drop but are not associated with an increased risk of complications (bleeding, postoperative infection, and prolonged urinary leak). Also, there is no deterioration in renal function after either single- or multiple-tract PCNL.

RESULTSThe mean ( SD , range) operative duration in groups I, II and III, respectively, were 138. 2 (52.7, 60-310), 121.4 (42.8, 70-250) and 112.5 (51.5, 55-310) min; the decrease in haemoglobin level was 3.2, 2.6 and 1.6 g/ dL, respectively, and continued to decrease with improvements in technique. With increasing experience, the number of stages required for stone clearance and the number of tracts required decreased exponentially. Most of the severe complications occurred early in our experience. The stone clearance rate in groups I, II and III was 81%, 86% and 93%, respectively, after completing the procedure; the overall clearance rate with observation/auxiliary procedures was 86%, 89% and 96%, respectively. The mean hospital stay for groups I, II and III was 11.1 (3.9, 7-25), 9.5 (3.4, 5-22) and 7.1 (3.6, 4-28) days, respectively. CONCLUSIONThe percutaneous management of staghorn calculi requires considerable expertise. Our data suggest that 'multiperc' PCNL is difficult to learn and requires experience. Although over the years our results improved, complete clearance remains a challenge. A constant review and application of newer techniques and results will improve the overall clearance rates further.

We believe that our alterations in the standard technique of PCNL with the use of pediatric instruments can make it a safe and effective option in the modern management of pediatric urolithiasis.