Purpose: Various minimally invasive approaches to reduce pain during extracorporeal shock wave lithotripsy (ESWL) have been described. We compared petroleum jelly (Vaselinet) and ultrasound gel in vitro as a contact medium based on the stone fragmentation rate. The analgesic effect of cutaneous petroleum jelly was tested against eutectic mixture of local anesthesia. We also evaluated the outcome of ESWL in a large group of patients treated with petroleum jelly.
Materials and methods: In vitro 3 artificial stones were completely fragmented with a MFL 5000* lithotriptor using petroleum jelly or ultrasound gel as a contact medium. A total of 110 patients (group 1) received petroleum jelly before treatment with the same lithotriptor. After retrospective analysis of group 1 we matched 32 patients (group 2) receiving cutaneous eutectic mixture of local anesthesia. Because of the favorable results with petroleum jelly, we used it in another 148 patients, for a total of 258 patients (group V). Treatment dependent pain was scored using a questionnaire as 1--no, 2--minor, 3--tolerable and 4--intolerable. ESWL without additional analgesics had a pain score of 1 to 3.
Results: In vitro petroleum jelly had a superior fragmentation rate compared to ultrasound gel. Our long-term experience with the lithotriptor indicated that only 30% of patients required no additional analgesics with cutaneous ultrasound gel. In contrast, no additional analgesics were needed in only 38% of group 2 compared to 81.8% of group V. The stone fragmentation rate did not differ statistically between groups.
Conclusions: Cutaneous petroleum jelly offers a noninvasive, highly effective, inexpensive treatment modality with no side effects and significant reduction in pain. This ointment is our contact medium of choice.