CU 26. Renal access by urologists versus sonographers during percutaneous nephrolithotomy

Objective: To evaluate the outcomes and complications of percutaneous access by urologist or sonographer following percutaneous nephrolithotomy (PCNL) at a single institution.

Methods: A retrospective chart review was performed for 420 renal calculi patients who underwent ultrasound-guided PCNL from March 2004 to May 2010 in our hospital. Patients were stratified into two groups according to percutaneous access by urologist (group 1, n=105) or sonographer (group 2, n=315). A predicted access difficulty score was calculated based on demographic, stone, and operative variables. Percutaneous access complications and stone-free rates were compared between these two groups.

Results: The use of multiple access tracts (3.2% vs. 4.4%; P=0.67), mean stone diameter (4.3±1.7 cm vs. 4.6±2.1 cm; P=0.65), and mean access difficulty parameters were comparable between groups. The percentage of staghorn calculi (25% vs. 28%; P=0.69) and number of obese (body mass index >30) patients (12% vs. 16%; P=0.85) were also comparable between groups 1 and 2. The complication rate was almost the same in the two groups (8.2% vs. 7.5%; P=0.59), and so was the overall stone-free rate (93.5% vs. 91.8%; P=0.32). Access by sonographer failed in 12.8% of the patients, which made additional access tract placement during the surgery.

Conclusions: Access established by sonographer often is not adequate for PCNL. Urologist-obtained access is safer and more effective for PCNL than sonographer.