Use of chemical warming packs during delivery room resuscitation is associated with decreased rates of hypothermia in very low-birth-weight neonates

Adv Neonatal Care. 2011 Oct;11(5):357-62. doi: 10.1097/ANC.0b013e318229aa8f.


Background: : Hypothermia is an independent contributor to neonatal mortality. All very low-birth-weight (VLBW) newborns have the potential to undergo cold stress or frank hypothermia during delivery room stabilization. Thus, clinicians aiming to maintain normothermia in VLBW neonates are compelled to use multiple adjuncts of unknown efficacy or safety.

Objective: : To evaluate the effectiveness of thermoregulation procedures in maintaining normothermia during delivery room resuscitation and to assess the impact of an unanticipated change in equipment at our institution on the admission temperatures of VLBW newborns.

Design/methods: : Institutional review board-approved, retrospective analysis of quality assurance data submitted to the Vermont-Oxford Network (VON) for 24 consecutive months starting January 2006. We compared the rate of hypothermia (admission temperature < 36.5°C) in our NICU during 2006 with the aggregate rates reported by VON. We then compared the rates of hypothermia and mean admission temperatures in our NICU during period 1 (when chemical warming packs were used routinely, in addition to plastic wrapping and warm blankets) and period 2 (after packs were discontinued owing to an incident of focal skin injury).

Results: : In 2006, 42% of VLBW babies in our NICU had an admission temperature of less than 36.5°C compared with the VON rate of 61% (interquartile range 48%, 76%). During period 1, 39% of 183 VLBW neonates were hypothermic compared with 68% of 103 during period 2 (P < .001). Mean admission temperatures during periods 1 and 2 were 36.5°C and 36.1°C, respectively (P < .001). A control chart showed the shift in temperatures occurring as period 2 began. No change in practice other than discontinuation of the warming packs was instituted during period 2. The incidence of temperatures greater than 38°C (hyperthermia) was 1.6% during period 1 and 1.0% during period 2.

Conclusions: : The results associated with this isolated change in practice at our institution suggest that chemical warming packs were a useful adjunct in achieving above-average rates of normothermia during delivery room resuscitation of VLBW newborns. Their potential adverse effects should be weighed against the increased risk of mortality associated with hypothermia in this population.

Publication types

  • Evaluation Study

MeSH terms

  • Body Temperature Regulation
  • Heating / methods*
  • Humans
  • Hypothermia / epidemiology*
  • Hypothermia / prevention & control*
  • Hypothermia / therapy
  • Infant, Newborn
  • Infant, Very Low Birth Weight
  • Intensive Care Units, Neonatal
  • Logistic Models
  • New York / epidemiology
  • Resuscitation
  • Retrospective Studies
  • Thiosulfates / therapeutic use*
  • Treatment Outcome


  • Thiosulfates
  • sodium thiosulfate