Should mini percutaneous nephrolithotomy (MiniPNL/Miniperc) be the ideal tract for medium-sized renal calculi (15-30 mm)?

INTRODUCTION: Reducing the percutaneous nephrolithotomy (PCNL) tract size reduces the morbidity associated with the procedure. Prolonged procedure time is a concern. Modification in technique required is to fragment the stone into smaller particles and remove them using the vacuum cleaner effect. This prospective study compares the efficacy and morbidity of reducing the tract size from the standard 24-16.5 Fr for stones sized from 16 to 30 mm. METHODS: 123 patients were enrolled in this prospective study and distributed into 2 groups based on the tract size used (group A 16.5/17.5 Fr Miniperc, N = 61 and group B: 22/24 Fr standard PCNL, N = 62). Critical factors assessed were procedure time, fluoroscopy time, blood loss, pain score, stone clearance status and complications. RESULTS: Both the groups were comparable with respect to age, creatinine and stone size. The blood loss (hemoglobin and PCV drop) was significantly less for group A (p < 0.001). Both the groups were comparable with regards to the pain score (p > 0.05). Nephrostomy was placed in 3 patients in group A and 14 patients in group B (p = 0.01). There was no significant difference in the procedure time amongst the 2 groups. A total of 9 patients (4 in group A and 5 in group B) had residual fragments greater than 3 mm. CONCLUSION: The 16.5 Fr Miniperc tract offers lower morbidity in terms of blood loss and maintains stone clearance comparable to larger 24 Fr tract size. It should be the ideal size used for medium sized renal stones.

Percutaneous nephrolithotomy for complex pediatric renal calculus disease.

BACKGROUND AND PURPOSE: Pediatric renal calculus disease has been a management dilemma in view of the concern about the effects of the various treatment modalities on the growing kidney, the significant recurrence rate, and the long-term outcome. We report our experience with percutaneous nephrolithotomy (PCNL) monotherapy in staghorn or complex pediatric renal calculi. PATIENTS AND METHODS: We retrospectively analyzed the case records of 116 patients younger than 15 years who underwent PCNL. The stones included 56 complex calculi. We defined complex calculi as either staghorn (complete or partial) or those with a large bulk and involving more than one calix, the upper ureter, or both. RESULTS: Complete clearance was achieved in 50 patients (89.8%). Of these, 22 (39%) required a single tract, while 34 (61%) required multiple tracts. With subsequent SWL, the clearance rate increased to 96%. The average hemoglobin drop was 1.9 g/dL. Assessing the factors affecting the hemoglobin drop, the number of tracts and the size of tracts were found to be significant (P<0.01). The average change in the serum creatinine concentration between the preoperative and postoperative measurements was +0.03 mg/dL and was not different in patients with a single tract and those with multiple tracts (+0.02 and +0.04 mg/dL, respectively; P=NS). Intravenous urography done in 36 renal units postoperatively revealed good function in all. A DMSA renal scan in six children showed no scar. CONCLUSIONS: 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.

A prospective randomized comparison of type of nephrostomy drainage following percutaneous nephrostolithotomy: large bore versus small bore versus tubeless.

PURPOSE: We compared postoperative outcomes among tubeless, conventional large bore nephrostomy drainage and small bore nephrostomy drainage following percutaneous nephrostolithotomy (PCNL) in a prospective randomized fashion. MATERIALS AND METHODS: Between January and June 2001, 30 patients undergoing PCNL were randomized to receive conventional large bore (20Fr) nephrostomy drainage (group 1, 10 patients), small bore (9Fr) nephrostomy drainage (group 2, 10 patients) or no nephrostomy drainage (group 3, 10 patients). Inclusion criteria included a single subcostal tract, uncomplicated procedure, normal preoperative renal function and complete stone clearance. Factors compared among the 3 groups were postoperative analgesia requirement, urinary extravasation, duration of hematuria, duration of urinary leak, decrease in hematocrit and hospital stay. RESULTS: The postoperative analgesic requirement was significantly higher in group 1 (217 mg) compared to groups 2 (140 mg, p <0.05) and 3 (87.5 mg, p <0.0001). Patients in group 3 had a significantly shorter duration (4.8 hours) of urinary leak through the percutaneous renal tract compared to patients in groups 1 (21.4 hours, p <0.05) and 2 (13.2 hours, p <0.05). Hospital stay was significantly shorter in group 3 (3.4 days) compared to groups 1 (4.4 days, p <0.05) and 2 (4.3 days, p <0.05). All 3 groups were similar in terms of operative time, duration of hematuria and decrease in hematocrit. Postoperative ultrasound did not reveal significant urinary extravasation in any case. CONCLUSIONS: 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.