Percutaneous nephrolithotomy under conscious sedation in morbidly obese patients.

Two morbidly obese males weighing 159 kg and 184 kg underwent percutaneous nephrolithotomy (PCNL) for large, symptomatic renal stones. To avoid anesthetic complications and cardiorespiratory compromise in the prone position, the procedures were performed under IV sedation with local anesthesia. The risks of PCNL in this patient population are reviewed, and the technique employed to mitigate the risks in these two cases is described.