PURPOSE: Preliminary studies have shown aminocaproic acid (AMICAR), an inhibitor of fibrinolysis, reduced the incidence of intracranial hemorrhage and significant surgical site bleeding in patients on extracorporeal membrane oxygenation (ECMO). The purpose of this analysis is to determine if these benefits remain when AMICAR is used in a large population. METHODS: ECMO patients from a single pediatric institution, with routine use of AMICAR for "high-risk" patients, were evaluated retrospectively from 1991 to 2001. Data including diagnosis, duration of support, significant complications, and survival were recorded. These variables were compared with those of the Extracorporeal Life Support Organization (ELSO), an international ECMO registry, using a chi2 test. P less than.05 was deemed significant. RESULTS: ECMO was used 431 times during the 10-year study period. A total of 298 patients received AMICAR, most frequently for surgical procedures. The survival rate was not statistically different in the study group when compared with the ELSO Registry (P =.06). The rate of neonatal intracranial hemorrhage was not significantly different between the 2 groups (P =.133); however, the rate of surgical site bleeding was significantly reduced in the study population (P =.005). Decrease in surgical site bleeding was particularly evident in cardiac patients (P <.001). CONCLUSIONS: In this large experience, use of AMICAR for high-risk patients on ECMO did not appear to alter the rate of neonatal intracranial hemorrhage, but did significantly reduce the incidence of surgical site bleeding. AMICAR remains a valuable tool for the prevention of hemorrhage in patients undergoing operation prior to or while on ECMO.