Four analgesic techniques for shockwave lithotripsy: eutectic mixture local anesthetic is a good alternative

Various sedative and analgesic medication has been used for shockwave lithotripsy (SWL). The aim of this study was to evaluate the efficacy of different anesthesia modalities in these patients.

One hundred patients were randomly divided into four groups. The first (Group F) received fentanyl 1 microg/kg intravenously (IV), the second (Group D) received diclofenac sodium 1 mg/kg intramuscularly (IM), the third (Group T) received tramadol 1.5 mg/kg IM, and the fourth (Group E) was given 15 g of eutectic mixture local anesthetic (EMLA) cream containing lidocaine and prilocaine. After routine preoperative evaluation, all patients received midazolam 2 mg IV 5 minutes before lithotripsy for sedative premedication. In all groups, a supplemental 25-microg bolus of fentanyl was administered IV when patients complained of pain, moved, or grimaced in response to the shockwaves. Pain intensity was evaluated on a 0- to 100-mm visual analog scale (VAS). The level of sedation was determined using the Observer's Assessment of Alertness/Sedation (OAS/S). Side effects such as bradypnea, oxygen desaturation, bradycardia, pruritus, and nausea and vomiting were recorded.

There were no statistically significant differences among the four groups with regard to VAS, OAS/S scores, or side effects. In Group F, the mean arterial pressure was decreased significantly at 10 and 20 minutes. The patients in this group also manifested a decrease of oxygen saturation at the first, tenth, and twentieth minutes and the end of SWL.

Application of EMLA cream was as safe and effective as fentanyl, diclofenac, and tramadol, and reduction of the fentanyl dose during SWL was possible.