A comparative randomized double-blind study between 99 patients with (group 1) and 100 without (group 2) cutaneous
anesthesia with a
lidocaine-prilocaine cream during extracorporeal
shock wave
lithotripsy (ESWL*) with an unmodified Dornier HM3 lithotriptor was done. The application of the
anesthetic cream or a placebo preparation was used in addition to
premedication with
meperidine hydrochloride and
diazepam. In case of
pain experience additional doses of
analgesic sedation were administered. The requirement of additional
analgesic sedation at a generator voltage of 14 kv. was significantly higher in group 2 than in group 1 (42 versus 26 patients, p < 0.05). The ESWL treatment was completed with only
premedication in 39% of the patients in group 2 compared with 50% in group 1. The
pain experience at 14 kv. was significantly lower for male patients in group 1 (p < 0.01). The most pronounced difference between groups 1 and 2 was recorded during treatment of stones in the upper calices, whereby 22% and 79%, respectively, required additional
analgesic sedation at a generator voltage of 14 kv. (p < 0.05). A less pronounced but still significant difference was also recorded at 14 kv. for patients with stones in the other parts of the kidney and ureter (p < 0.05). The maximal median energy settings in groups 1 and 2 were 15.9 kv. and 15.4 kv., respectively. There were 27 patients in group 2 and 18 in group 1 who were treated with a maximum of 14 kv. The overall requirement of additional
analgesic sedation was 62% in group 2 and 51% in group 1. Cutaneous
anesthesia with
lidocaine-prilocaine cream obviously has clinically significant effects on
pain experience during ESWL. It cannot replace the need for
analgesic sedation but it can be used advantageously to reduce the dosage of
analgesic and
sedative drugs during ESWL treatments performed without regional or
general anesthesia in the unmodified Dornier HM3 lithotriptor.