Does Head Cooling With Mild Systemic Hypothermia Affect Requirement for Blood Pressure Support?

Abstract

Our goal was to evaluate whether head cooling with mild systemic hypothermia for neonatal encephalopathy is associated with greater requirement for volume or inotrope support. We studied term infants (>/=36 weeks) with moderate-to-severe neonatal encephalopathy plus abnormal amplitude integrated electroencephalography, randomly assigned to head cooling for 72 hours starting within 6 hours of birth, with the rectal temperature maintained at 34.5 degrees C +/- 0.5 degrees C (n = 112), or conventional care (n = 118). This was a multicenter randomized, controlled study (the CoolCap trial). The primary outcome was the time relationship between mean arterial blood pressure and subsequent administration of inotropes or volume administration. Pooled data from 0 to 76 hours after randomization revealed no difference in mean arterial blood pressure between groups and significantly lower mean heart rate during cooling. The use of inotropes or volume was related to preceding mean arterial blood pressure and not to treatment group in the first 24 hours. In contrast, from 24 to 76 hours, there was no effect of mean arterial blood pressure, but there was an overall reduction in pressure support over time and significantly more frequent pressure support in the cooled group than in controls. Mild systemic hypothermia did not affect arterial blood pressure or initial treatment with inotropes or volume in infants with moderate-to-severe encephalopathy but was associated with an apparent change in physician behavior, with slower withdrawal of therapy in cooled infants.