Maintaining normal temperature immediately after birth in late preterm and term infants: A systematic review and meta-analysis

Abstract

Aim

Prevention of hypothermia after birth is a global problem in late preterm and term neonates. The aim of this systematic review and meta-analysis was to evaluate delivery room strategies to maintain normothermia and improve survival in late preterm and term neonates (≥34 weeks’ gestation).

Methods

Medline, Embase, CINAHL, CENTRAL and international clinical trial registries were searched. Randomized controlled trials (RCTs), quasi-RCTs and observational studies were eligible for inclusion. Risk of bias for each study and GRADE certainty of evidence for each outcome were assessed.

Results

25 RCTs and 10 non-RCTs were included. Room temperature of 23 °C compared to 20 °C improved normothermia [Risk Ratio (RR), 95% Confidence Interval (CI): 1.26, 1.11–1.42)] and body temperature [Mean Difference (MD), 95% CI: 0.30 °C, 0.23–0.37 °C), and decreased moderate hypothermia (RR, 95% CI: 0.26, 0.16–0.42). Skin to skin care (SSC) compared to no SSC increased body temperature (MD, 95% CI: 0.32, 0.10–0.52), reduced hypoglycemia (RR, 95% CI: 0.16, 0.05–0.53) and hospital admission (RR, 95% CI: 0.34, 0.14–0.83). Though plastic bag or wrap (PBW) alone or when combined with SSC compared to SSC alone improved temperatures, the risk–benefit balance is uncertain. Clinical benefit or harm could not be excluded for the primary outcome of survival for any of the interventions. Certainty of evidence was low to very low for all outcomes.

Conclusions

Room temperature of 23 °C and SSC soon after birth may prevent hypothermia in late preterm and term neonates. Though PBW may be an effective adjunct intervention, the risk–benefit balance needs further investigation.

Introduction

Neonatal hypothermia is a global issue with significant consequences.¹ Although the risk of both hypothermia and its consequences increase with decreasing gestation, hypothermia in the initial postnatal hours is also associated with higher mortality and morbidity in late preterm and term infants.1, 2, 3, 4, 5 Several systematic reviews have examined prevention of hypothermia after birth in very and extremely preterm neonates.6, 7, 8 An evidence update evaluation for the International Liaison Committee on Resuscitation (ILCOR) Neonatal Life Support Task Force of strategies to prevent hypothermia in infants <32 weeks’ gestation found sufficient new studies to justify updating the ILCOR systematic review.9, 10 Meanwhile, an additional 2015 ILCOR systematic review examining prevention of hypothermia in ≥30 week gestation infants born in low-resourced settings found no evidence,¹⁰ but more recent literature-tracking suggested that new evidence was available. The task force decided to conduct separate reviews for preterm newborn infants <34 weeks and for those ≥34 weeks’ gestation, on the basis that both base-line risk and important and critical outcomes were expected to differ markedly by gestation.

Recognising the important adverse consequences of hypothermia, the World Health Organisation (WHO) advocates ten steps of a ‘warm chain’ to prevent it in neonates immediately after birth.¹¹ Despite these decades-old recommendations, neonatal hypothermia remains a serious, prevalent problem.¹² Furthermore, the evidence for strategies that are effective in very preterm neonates such as the use of a plastic bag or wrap (PBW), thermal mattress (TM) or heated, humidified gases for resuscitation has not been systematically reviewed for term and late preterm infants.¹³ Therefore, this systematic review aimed to evaluate a wide range of strategies initiated in the minutes after birth for preventing hypothermia and improving short-term outcomes including survival to discharge in late preterm and term neonates.