Therapeutic hypothermia increases the risk of cardiac arrhythmia for perinatal hypoxic ischaemic encephalopathy: A meta-analysis

To determine whether therapeutic hypothermia after hypoxic ischaemic encephalopathy (HIE) in neonates increases the risk of cardiac arrhythmia during intervention. A meta-analysis was conducted using a fixed-effect model. Risk ratios, risk differences, and 95% confidence intervals, were measured. Studies identified from the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Google Scholar, previous reviews, and abstracts from onset to August, 2016. Reports that compared therapeutic hypothermia with normal care for neonates with HIE and that included data on safety or cardiac arrhythmia, which is of interest to patients and clinicians, were selected. We found seven trials, encompassing 1322 infants that included information on safety or cardiac arrhythmia during intervention. Therapeutic hypothermia considerably increased the combined rate of cardiac arrhythmia in the seven trials (risk ratio 2.42, 95% confidence interval 1.23 to 4.76. p = 0.01; risk difference 0.02, 95% CI 0.01 to 0.04) during intervention. In infants with hypoxic ischaemic encephalopathy, therapeutic hypothermia is associated with a consistent increase in cardiac arrhythmia during intervention.