To Örebro University

AIM: Swedish guidelines for therapeutic hypothermia (TH) after perinatal asphyxia were established in 2007, following several randomised studies that demonstrated improved outcomes. We assessed the implementation of hypothermia treatment in a mid-Swedish region with a sizeable proportion of outborn infants.

METHOD: A population-based TH cohort from 2007 to 2015 was scrutinised for adherence to national guidelines, interhospital transport, including the use of a cooling mattress made of phase change material for thermal management, and outcomes.

RESULTS: Of 136 admitted infants, 99 (73 %) were born outside the hospital. Ninety-eight percent fulfilled the criteria for postnatal depression/acidosis, and all patients had moderate-to-severe encephalopathy. Treatment was initiated within 6 h in 85 % of patients; amplitude-integrated electroencephalography/electroencephalography was recorded in 98 %, cranial ultrasound in 78 %, brain magnetic resonance imaging in 79 %, hearing tests in all, and follow-up was performed in 93 %. Although target body temperature was attained later (p < 0.01) in outborn than in inborn infants, at a mean (standard deviations) age of 6.2 (3.2) h vs 4.4 (2.6) h, 40 % of those transported using the cooling mattress were already within the therapeutic temperature range on arrival, and few were excessively cooled. The mortality rate was 23 %, and 38 % of the survivors had neurodevelopmental impairment at a median of 2.5 years.

CONCLUSION: The regionalisation of TH, including interhospital transport, was feasible and resulted in outcomes comparable to those of randomised controlled studies.