Hypothermia to treat neonatal hypoxic ischemic encephalopathy

Objectives: To systematically review the effectiveness, as determined by survival without moderate to severe neurodevelopmental disability in infancy and childhood, and the safety of hypothermia vs normothermia in neonates with postintrapartum hypoxic-ischemic encephalopathy and to perform subgroup analyses based on severity of encephalopathy ( moderate or severe), type of hypothermia ( systemic or selective head cooling), and degree of hypothermia ( moderate [<= 32.0-33.5 degrees C] or mild [>= 33.6 degrees C]). Data Sources: MEDLINE, EMBASE, CINAHL ( Cumulative Index for Nursing and Allied Health Literature), the Cochrane Library, abstracts of annual meetings of the Pediatric Academic Societies, and bibliographies of identified articles. Study Selection: Randomized and quasi-randomized controlled trials without language restriction were assessed by 2 reviewers independently and discrepancies were resolved by involving a third reviewer. Quality of the trials was assessed on the basis of concealment of allocation, method of randomization, masking of outcome assessment, and completeness of follow-up. Intervention: Systemic or selective head hypothermia compared with normothermia. Main Outcome Measure: Death or moderate to severe neurodevelopmental disability. Results: Eight studies of acceptable quality were included. The combined outcome of death or neurodevelopmental disability in childhood was reduced in infants receiving hypothermia compared with control infants ( 4 studies including 497 infants; relative risk, 0.76, 95% confidence interval, 0.65-0.88; number needed to treat, 6; 95% confidence interval, 4-14), as were death and moderate to severe neurodevelopmental disability when analyzed separately. Cardiac arrhythmias and thrombocytopenia were more common with hypothermia; however, they were clinically benign. Conclusions: In neonates with postintrapartum asphyxial hypoxic-ischemic encephalopathy, hypothermia is effective in reducing death and moderate to severe neurodevelopmental disability in combination or separately and is a safe intervention.