Hypothermia Therapy in Pediatric Cardiac Intensive Care Unit for Suspected for Brain Injury

Inclusion Criteria: 1. Every child entering the PCICU, age \< 7 years 2. The child will enter arm 1 or 2 if he underwent the event described in section 3. 3. Hypoxic ischemic event that would render hypothermia treatment is defined as * During the hospitalization in the PCICU before or after the surgery: Resuscitation comprised of chest compressions for more than 2 minutes, and the first blood tests immediately after the resuscitation show a serum lactate level of more than 90 mg/dl OR Resuscitation comprised of chest compressions for more than 2 minutes, and the first blood tests immediately after the resuscitation shows a serum lactate level of more than 40 mg/dl and a blood pH level of less than 7.1 * During the surgery Near infra red spectroscopy lower than 40 for more than 5 minutes AND Serum lactate levels of more than 90 mg/dl during the event OR The patient is re-connected to cardio-pulmonary bypass machine as a result of the event 4. Initiation of hypothermia treatment within 6 hours following the hypoxic ischemic event defined in section 3. Exclusion criteria * Suspected hypoxic ischemic event as described in the Inclusion Criteria in the 2 weeks prior to the PCICU admission * Prolonged low cerebral perfusion before the PCICU admission, with 3 repeated tests in 1 hour of lactate level higher than 40 mg/dl and pH lower than 7.1 * Rejection criteria * A second resuscitation after the hypoxic ischemic event and before a brain MRI is done