Therapeutic Hypothermia After Perinatal Asphyxia in Infants With Severe, Ductal-Dependent Congenital Heart Disease

Objectives: Patients with severe congenital heart disease and cardiac anomalies such as restrictive foramen ovale, intact atrial septum, or narrowing of ductus arteriosus are at risk for perinatal asphyxia, leading to hypoxic-ischemic encephalopathy. We hypothesize that therapeutic hypothermia can be applied to these patients and seek to investigate feasibility and safety of this method. Design: A retrospective observational study. Setting: The Department of Neonatology of Charite, University Hospital, Berlin, Germany. Patients: Newborns with severe congenital heart disease and perinatal asphyxia were retrospectively analyzed over a 6-year period. Interventions: Application of therapeutic hypothermia. Measurements and Main Results: Ten patients with perinatal asphyxia were enrolled in this study. All patients received low-dose prostaglandin E1 for ductal maintenance. Three patients without evidence for hypoxic-ischemic encephalopathy did not receive therapeutic hypothermia. One patient died at the age of 15 hours, and therapeutic hypothermia was discontinued after 19 hours in another patient with severe arterial hypotension. Adverse effects during hypothermia included respiratory insufficiency (100%), arterial hypotension (71%), the need for inotropic support (71%), and pulmonary hypertension (43%), the latter associated with prolonged postoperative inotropic support. No neurologic complications occurred before or after the surgery. Operative outcome of surviving patients was excellent. Early brain MRI scans were suggestive of good neurodevelopmental prognosis for most patients. Conclusions: Therapeutic hypothermia can be applied to patients with severe congenital heart disease and hypoxic-ischemic encephalopathy. Low-dose prostaglandin E1 infusions are safe for ductal maintenance during cooling, but cardiopulmonary adverse effects should be anticipated.