Anesthesia with Transcutaneous Electrical Nerve Stimulation and Intravenous Sedation during Shock Wave Lithotripsy

Abstract

Shock wave lithotripsy was carried out on the Northgate SD-3 Lithotripter in 26 patients using transcutaneous electrical nerve stimulation (TENS) for anesthesia plus intravenous sedation consisting of midazolam and fentanyl during the procedure. Nineteen patients required no additional anesthesia, and two patients experienced mild to moderate discomfort that was relieved by the injection of 0.5% bupivacaine directly into the skin and subcutaneous tissues at the shock wave entry site. Four patients required conventional anesthesia because of excessive pain during the lithotripsy procedure. One patient completed part of the lithotripsy treatment without additional anesthesia, but the procedure was terminated because of cardiac problems. Patients received an average of 2056 shocks at 10,000 to 11,500 PSI. Transcutaneous electrical nerve stimulation with IV sedation appears to be an effective alternative to conventional anesthetic techniques for shock wave lithotripsy. It is readily adaptable to the tubless second-generation lithotripters and can be used with units that produce focused electrohydraulic shock waves for calculus fragmentation.