The neuropathologic autopsy findings of a group of infants and children at Children's Hospital of Pittsburgh who died after treatment with extracorporeal membrane oxygenation (ECMO) were reviewed and tabulated. The study surveyed an 11-year period (February, 1980 to May, 1991); of 268 children receiving ECMO therapy for severe cardiopulmonary failure, 94 patients died, 70 of whom were autopsied and permission for brain examination was granted in only 44. The frequency of ischemic neuronal necrosis (50%), focal cerebral infarcts (50%), intracerebral hemorrhages (52%), and periventricular leukomalacia (41%) was higher in this group of ECMO-treated patients than that observed in the general autopsy population from which the study patients were selected. The frequency of ischemic and hemorrhagic brain lesions was similar among neonates and older infants and children. This documentation of cerebrovascular lesions in children dying after ECMO may provide a better understanding of potential brain damage in the larger population of infants and children who survive this invasive procedure.