Efficacy of local subcutaneous anesthesia versus intramuscular opioid sedation in extracorporeal shockwave lithotripsy: a randomized study.

Purpose: To evaluate the analgesic efficacy of local subcutaneous (SC) anesthesia compared with intramuscular (IM) opioid sedation during extracorporeal shockwave lithotripsy (SWL) in a randomized study.
Patients and Methods: After informed consent was obtained, 125 patients with urolithiasis who were scheduled for SWL were included in the study. The patients in each treatment session were randomized to receive either IM meperidine (group A) or SC infiltration of 10 mL 2% lidocaine and 10 mL 0.5% bupivacaine at the area of shockwave entry (group B). Degree of pain was rated by the patient using a five-point visual analogue scale (VAS).
Results: The study included 88 (70.4%) men and 37 (29.6%) women with a mean age of 47.6 ± 12.5 years and a mean body mass index (BMI) of 28.16 ± 4.67 kg/m2. Of the patients, 89, 26, and 10 received a single, two, or more than two treatment sessions, respectively (176 sessions). Maximum stone length was 10.68 ± 5.12 mm. Pretreatment stent placement was performed in 17 (13.6%) patients (28 sessions). Group A comprised 89 treatment sessions while 87 were involved in group B. Both groups were similar. Supplemental intrvenous sedation was needed in two (2.5%) and four (4.6%) sessions in groups A and B, respectively. VAS was not different between both groups (P = 0.063). Patients with pretreatment stent placement had significantly lower VAS score compared with patients without stents (P = 0.012). Sex and BMI had no impact on the VAS score.
Conclusions: Local SC anesthesia alone is effective for analgesic purposes during extracorporeal SWL. Sex, age, and BMI have no relation to analgesia requirement.