Therapeutic hypothermia is now the standard of care for hypoxic-ischemic encephalopathy. Treatment should be started early, and it is often necessary to transfer the infant to a regional NICU for ongoing care. There are no large studies reporting outcomes from infants cooled passively compared with active (servo-controlled) cooling during transfer. Our goal was to review data from a regional transport service, comparing both methods of cooling.
This was a retrospective observational study of 143 infants referred to a regional NICU for ongoing therapeutic hypothermia. Of the 134 infants transferred, the first 64 were cooled passively, and 70 were subsequently cooled after purchase of a servo-controlled mattress. Key outcome measures were time to arrival at the regional unit, temperature at referral and arrival at the regional unit, and temperature stability during transfer.
The age cooling was started was significantly shorter in the actively cooled group (46 [0–352] minutes vs 120 [0–502] minutes; <.01). The median (range) stabilization time (153 [60–385] minutes vs 133 [45–505] minutes; = .04) and age at arrival at the regional unit (504 [191–924] minutes vs 452 [225–1265]) minutes; = .01) were significantly shorter in the actively cooled group. Only 39% of infants passively cooled were within the target temperature range at arrival to the regional unit compared with 100% actively cooled.
Servo-controlled active cooling has been shown to improve temperature stability and is associated with a reduction in transfer time.