Anesthetic requirements during electromagnetic extracorporeal shock wave lithotripsy

An important aspect of modern extracorporeal shock wave lithotripsy is the ability to perform the procedure without anesthesia. Between June 1987 and April 1990, a total of 7,500 treatments were performed in our Lithotripsy Unit, using the Lithostar (Siemens AG, Erlangen, FRG): moreover 80% of the treatments were carried out as an anesthesia-free outpatient service. All treatments were reviewed for anesthetic requirements. Epidural anesthesia was performed in 74/7,500 (0.98%) treatments: during the initial period, the first 70 procedures were systematically performed under epidural anesthesia, and in 4 later cases of simultaneous endoscopic stone manipulation. Local skin infiltration was applied at the coupling site in 658/7,500 (8.7%) treatments. With increasing experience and technological improvement, 6,229/7,500 (83%) procedures were performed later on with only mild sedation: 1 mg of lorazepam orally 30 min before the treatment. Intravenous sedation was required in 510/7,500 (6.8%) cases because of painful local irritation, especially when treating calculi close to sites where shock waves can progress along the ribs. General anesthesia was required in all 28 children (0.4%).