Factors associated with hypothermia within the first 6 hours of life in infants born at ≥34 weeks' gestation: a multivariable analysis.

BACKGROUND

Lack of appropriate temperature management has been associated with significant adverse outcomes in preterm and low birthweight neonates. There is a lack of similar investigations in the late preterm (34-36) and term (≥37) neonate population. Our aim was to identify key risk factors as well as clinical outcomes associated with hypothermia in this population.

METHODS

A retrospective chart review was conducted at the Ottawa Hospital including all eligible infants ≥34 weeks' gestation over a one-month period in November 2020. Infant, maternal, and delivery room variables were collected, including prematurity, maternal temperature, delivery mode, birthweight, and premature rupture of membranes, as well as clinical outcomes such as NICU/SCN admission and length of stay. Regression models were generated, adjusted for covariates, and stepwise regression was performed.

RESULTS

Four hundred forty infants were included in the analysis; 26.8% (118/440) were hypothermic within 6 hours of delivery. In the multivariable analysis, prematurity, low 5 minute Apgar score (< 7) or need for resuscitation, maternal hypertension, and absence of premature rupture of membranes > 18 hours or suspected maternal infection were significantly associated with hypothermia within 6 hours of delivery (p < 0.05). Multivariable analysis of clinical outcomes demonstrated a significant association between hypothermia within 6 hours of delivery and NICU/SCN admission (OR = 2.87; 95% CI 1.36, 6.04), need for respiratory support or diagnosis of respiratory distress syndrome (OR = 3.94; 95% CI 1.55, 10.50), and length of stay (exp(β) = 1.20; 95% bootstrap CI 1.04, 1.37).

CONCLUSIONS

Our results suggest there are similar factors associated with hypothermia in our study population of infants born at ≥34 weeks' gestation compared to prior studies in preterm and low-birthweight infants. Furthermore, hypothermia is associated with higher risk of adverse outcomes, which highlights the need to prevent hypothermia in all newborns.