Theophylline Prophylaxis During Hypothermia to Limit Neonatal Nephron Damage

Inclusion Criteria: * gestational age at birth \>= 35 weeks by best obstetrical dating * birth weight \> 1800 grams * clinical determination of HIE and treatment with hypothermia being initiated within six hours of birth according to institutional guidelines * no known congenital abnormalities involving the brain, kidneys, heart or lungs * ability to administer theophylline via intravenous route within 18 hours of birth Exclusion Criteria: * infants with suspected or diagnosed significant renal, urinary tract, brain, heart, or lung abnormalities * infant with known chromosomal anomaly * evidence of head trauma or skull fracture causing major intracranial hemorrhage * inability to initiate hypothermia within six hours of birth * attending physician unwilling to have infant participate in the study * inability to obtain informed consent within 18 hours of birth