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

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 degrees C compared to 20 degrees 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 degrees C, 0.23-0.37 degrees 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 degrees 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

Respiratory changes in term infants immediately after birth

Introduction: Over 5% of infants worldwide receive breathing support immediately after birth. Our goal was to define references ranges for exhaled carbon dioxide (ECO2), exhaled tidal volume (VTe), and respiratory rate (RR) immediately after birth in spontaneously breathing, healthy infants born at 36 weeks' gestational age or older. Methods: This was a single-centre, observational study at the Royal Women's Hospital in Melbourne, Australia, a busy perinatal referral centre. Immediately after the infant's head was delivered, we used a face mask to measure ECO2, VTe, and RR through the first ten minutes after birth. Respiratory measurements were repeated at one hour. Results: We analysed 14,731 breaths in 101 spontaneously breathing infants, 51 born via planned caesarean section and 50 born vaginally with a median (IQR) gestational age of 39(1/7) weeks (38(3/7) -39(5/7)). It took a median of 7 (4-10) breaths until ECO2 was detected. ECO2 quickly increased to peak value of 48 mmHg (43-53) at 143 s (76-258) after birth, and decreased to post-transitional values, 31 mmHg (28-24), by 7 min. VTe increased after birth, reaching a plateau of 5.3 ml/kg (2.5-8.4) by 130 s for the remainder of the study period. Maximum VTe was 19 ml/kg (16-22) at 257 s (82-360). RR values increased slightly over time, being higher from minute five to ten as compared to the first two minutes after birth. Conclusions: This study provides reference ranges of exhaled carbon dioxide, exhaled tidal volumes, and respiratory rate for the first ten minutes after birth in term infants who transition without resuscitation

Maintaining normothermia immediately after birth in preterm infants <34 weeks' gestation: A systematic review and meta-analysis

Aim: To evaluate delivery room (DR) interventions to prevent hypothermia and improve outcomes in preterm newborn infants <34 weeks' gestation. Methods: Medline, Embase, CINAHL and CENTRAL were searched till 22nd July 2022. Randomized controlled trials (RCTs), non-RCTs and quality improvement studies were considered. A random effects meta-analysis was performed, and the certainty of evidence was evaluated using GRADE guidelines. Results: DR temperature of ≥23 °C compared to standard care improved temperature outcomes without an increased risk of hyperthermia (low certainty), whereas radiant warmer in servo mode compared to manual mode decreased mean body temperature (MBT) (moderate certainty). Use of a plastic bag or wrap (PBW) improved normothermia (low certainty), but with an increased risk of hyperthermia (moderate certainty). Plastic cap improved normothermia (moderate certainty) and when combined with PBW improved MBT (low certainty). Use of a cloth cap decreased moderate hypothermia (low certainty). Though thermal mattress (TM) improved MBT, it increased risk of hyperthermia (low certainty). Heated-humidified gases (HHG) for resuscitation decreased the risk of moderate hypothermia and severe intraventricular hemorrhage (very low to low certainty). None of the interventions was shown to improve survival, but sample sizes were insufficient. Conclusions: DR temperature of ≥23 °C, radiant warmer in manual mode, use of a PBW and a head covering is suggested for preterm newborn infants <34 weeks' gestation. HHG and TM could be considered in addition to PBW provided resources allow, in settings where hypothermia incidence is high. Careful monitoring to avoid hyperthermia is needed