Short-Term Changes of Laboratory Values after Extracorporeal Shock Wave Lithotripsy: A Comparative Study

Abstract

Since the inception of extracorporeal shock wave lithotripsy 9 years ago treatment strategies have changed. Patients currently are receiving larger numbers of higher voltage shock waves. However, upper limits of safety for these treatments have not been established. In an attempt to address this question of comparative study of effects of extracorporeal shock wave lithotripsy on laboratory values between 2 stone centers, Munich and Tucson, using different treatment strategies 3 to 4 years apart was done to identify possible differing effects. Patient stone burdens were similar. However, Tucson patients received almost twice the number of shock waves. Both groups showed a significant decrease in hematocrit (by 8.7 per cent in Munich and 6.4 per cent in Tucson). Both groups had a significant increase in white blood count (14.5 per cent in Munich and 22.7 per cent in Tucson). In addition, both groups had increased serum levels of glutamic oxaloacetic transaminase of 43.3 and 59.7 per cent, respectively. However, only the Tucson group showed increases in serum glutamic pyruvic transaminase, lactic dehydrogenase and total bilirubin in 51.5, 40.8 and 46 per cent of the patients, respectively. Further analysis indicated that extracorporeal shock wave lithotripsy was associated with 2 significant short-term changes of blood or serum laboratory values: 1) those presumed to be dilutional from related infusions, rather than extracorporeal shock wave lithotripsy treatments themselves and 2) those presumed to be related to cellular injury after high energy treatments. Elevated serum glutamic pyruvic transaminase, lactic dehydrogenase and total bilirubin values of Tucson patients clearly were related to higher kilovolts and number of shocks or to treatments on the right side. These observations probably resulted from transient trauma to the liver, as well as renal cells.