Rapid vs. Slow Rewarming for Management of Moderate to Severe Hypothermia in Low-Birth-Weight Pre-term Neonates-An Open Label Randomized Controlled Trial

Abstract

Background: Evidence is lacking regarding the optimal method of rewarming hypothermic low-birth-weight (LBW) pre-term neonates. We aim to evaluate the effect of rapid vs. slow rewarming in the management of moderate to severe hypothermia in LBW pre-term neonates. Methods: In this open label, randomized controlled trial, 100 LBW (<2.5 kg), pre-term (<37 weeks) neonates with moderate to severe hypothermia (<36°C) was randomized to two groups of 50 each and received either rapid (at >0.5°C/h) or slow (at ≤0.5°C/h) rewarming rate till normothermia. The primary outcome was stabilization score [TOPS (temperature, oxygenation, perfusion and saturation) and MSNS (modified sick neonatal score)] at baseline, 6 and 24 h and mortality until discharge. Other neonatal morbidities were assessed as secondary outcomes. Results: Mean TOPS score and MSNS score at baseline, 6 and 24 h of admission as well as change in score from baseline were similar between the two groups. The median rewarming rate [interquartile range (IQR)] was higher in rapid rewarming group than in the slow rewarming group [5.05°C/h (3.54-7.71) vs. 0.71°C/h (0.60-0.90); p < 0.001]. The median rewarming time taken in rapid rewarming group was lesser compared with that in the slow rewarming group [0.31 h (IQR 0.13-0.75) vs. 2.05 h (IQR 1.11-3.03); p < 0.001]. Mortality in rapid rewarming and slow rewarming group was similar [7/50 vs. 5/50; OR 1.46 (0.43-4.97), p = 0.538] Conclusion: Rapid rewarming was as effective and safe as slow rewarming in the management of moderate to severe hypothermia in LBW pre-term neonates with similar short-term neonatal outcomes. CTRI number: CTRI/2018/01/011187.