Transcutaneous Electrical Nerve Stimulator: An Approach to Anesthesia-Free Shock Wave Lithotripsy with the Lithostar Unit

Abstract

Extracorporeal shock wave lithotripsy (ESWL) has now evolved to the point where most treatments are rendered either without the need for anesthesia or with the use of only minimal, intravenous sedation. The Siemens Lithostar machine was originally designed to be used with intravenous sedation in combination with local anesthesia. Herein, we report use of a transcutaneous electrical nerve stimulator unit to achieve satisfactory analgesia in patients undergoing shock wave lithotripsy. Overall, 60% of patients were able to undergo treatment with only a TENS unit. More importantly, when the total number of shock waves was limited to 3,000 or fewer, 90% of patients were able to undergo therapy without any supplemental intravenous or local anesthesia. The TENS unit is inexpensive to use, noninvasive, has no associated morbidity, and allows for the same degree of stone fragmentation as is seen with more invasive forms of anesthesia.