Coagulation parameter instability as an early predictor of intracranial hemorrhage during extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) has been used to treat over 2,000 neonates with severe respiratory distress due to a number of different diagnoses. Its application has been expanded into the pediatric population as well. Despite both technical advances and refinement of management techniques, intracranial hemorrhage remains a major cause of both morbidity and mortality during ECMO. We reviewed our ECMO experience with regard to the diagnosis of intracranial bleeding, and gave particular attention to the technicians' written records. Seven of 50 patients had a documented intracranial event during ECMO, and in all 7, the technicians noted increasing difficulty with control of the activated clotting time (ACT), platelet count, or both. This manifested itself as both inability to raise the ACT and/or platelet count, or inability to decrease the ACT, despite discontinuation of heparin. The patients with intracranial hemorrhages had a significantly greater number of changes in the rate of heparin infusion than matched controls. None of the patients with intracranial bleeding had any signs of extracranial hemorrhage, and none manifested any hemodynamic abnormalities. In 4 cases, the regularly scheduled echoencephalogram was obtained earlier in the day, and the patients were subsequently weaned and decannulated. We conclude from this review that instability of previously well-controlled coagulation parameters is an early predictor of an intracranial event. However, the impact of earlier diagnosis on outcome is less clear from this small number of patients.