Hypothermia and adverse outcomes during the transfer of extremely low birth weight infants.

Abstract

We aimed to explore whether hypothermia during the transfer of extremely low birth weight (ELBW) infants was associated with increased morbidity and mortality. Retrospective cohort study of transfers of ELBW infants by the London Neonatal Transfer Service between April 2015 and January 2017. Hypothermia was defined as an axillary temperature below 36.5°C. Hypothermia was recorded in 36-47% of the 146 transfers depending on the time point of measurement from admission at the referring unit to admission at the receiving unit. Infants with hypothermia had a lower gestational age [25.1 (24.1-26.6) versus 26.0 (25.3-27.0) weeks, p < 0.001], birth weight [750 (600-830) versus 800 (730-885) gr, p = 0.004) and age at referral [1 (0.8-3) versus 1.5 (1-4) hours, p = 0.049] compared to infants without hypothermia. Infants with hypothermia had a longer median (IQR) duration of invasive ventilation [22(6-44) days] compared to infants without hypothermia [10 (4-21) days, p = 0.002]. Infants with hypothermia had a higher incidence of a patent ductus arteriosus and mortality before discharge from neonatal care compared to infants without hypothermia (79% vs. 27%, p = 0.043 and 29% vs. 13%, p = 0.025, respectively). Among ELBW infants, hypothermia during transfer was common, particularly in infants of lower gestational age. Hypothermia was associated with a longer duration of ventilation and increased mortality before discharge from neonatal care.