Prevalence and associated factors of hypothermia among neonates admitted to the premature baby unit of a secondary care hospital in Sri Lanka: a cross-sectional analytical study
Authors: Kasturiarachchi Savindi , Alwis Inosha , Kumara Sanath , Rajapaksha Buwanaka 
Published: November 2024

Background

Hypothermia is defined as core body temperature being below 36.5°C. This study aimed to identify the prevalence, associated factors and outcomes of hypothermia among neonates admitted to the premature baby unit (PBU) of a secondary care hospital in Nawalapitiya, Sri Lanka.

Methods

In a cross-sectional analytical study, medical records of neonates admitted to the PBU were selected retrospectively from March 2022 using consecutive sampling. The recorded axillary temperature on admission, socio-demographic and clinical data were extracted. Following bivariate analysis, multivariable logistic regression was performed.

Results

Among 407 neonates, the median admission age was 1 day. The majority were males (52.6%), were term (59%) and had a normal birth weight (52.5%). The prevalence of hypothermia was 38.6% (95% confidence interval (CI):33.9–43.4). Maternal factors like teenage pregnancy, multiple pregnancy, hypertension during pregnancy, premature rupture of membranes and lower-segment caesarean sections; neonatal factors like age on admission being less than 24 hours, prematurity, corrected gestational age on admission being less than 37 weeks, low birth weight, weight on admission being less than 2.5 kg and having been resuscitated at birth had statistically significant associations with hypothermia on the bivariate analysis. Hypothermia showed no significant association with the month of admission. Following multivariable analysis, age on admission being less than 24 hours (adjusted odds ratio (aOR):3.3, 95% CI:1.9-5.8), teenage pregnancy (aOR:8.2, 95% CI:1.8-37.2), multiple pregnancy (aOR:2.8, 95% CI:1.1-7.1) and hypertension in pregnancy (aOR:2.3, 95% CI:1.2-4.7) remained statistically significant. Neonates with hypothermia had 5.2 times (95% CI:1.8-14.6) odds of mortality and 4.9 times (95% CI:2.8-8.5) odds of receiving ventilatory support compared to normothermic neonates. Hypothermia also showed statistically significant associations with infant respiratory distress syndrome, metabolic acidosis and neonatal jaundice.

Conclusions

Nearly two out of five neonates admitted to the PBU were hypothermic. There were significant maternal and neonatal associations to be addressed. Hypothermia on admission may indicate serious neonatal morbidity and mortality.

Summary box

What is already known about this topic

Though hypothermia is known to be associated with neonatal morbidity and mortality, evidence of hypothermia on admission to healthcare settings is limited, especially in South Asia.

What this study adds

This study adds evidence on the prevalence of admission hypothermia among newborns, and the maternal, neonatal and environmental factors independently associated with it. It also highlights the specific neonatal complications to which hypothermia is linked.

How this study might affect research, practice or policy

These findings can be used to identify risk groups during neonatal care and inform advocacy and policy for thermo-protective interventions within hospitals.