Characteristics and Frequency of Hyponatremia in Newborns

Abstract

Background: Hyponatremia, defined as a serum sodium level below 135 meq/L, is a significant and often overlooked problem in neonatal intensive care unit. Local data on the severity and chronicity of hyponatremia in neonates is lacking. This study aimed to investigate the features, risk factors, and frequency of hyponatremia in infants admitted to our NICU. Objective: To determine the incidence, identifying potential risk factors, assessing its severity, as well as understanding the recovery period and the duration of hospital stay associated with hyponatremia in neonates. Study Design: Cross-sectional study. Settings: Study was conducted in Neonatal ICUs of Fatima Memorial Hospital, Lahore Pakistan. Duration: January to December 2022 (1 Year). Methods: Sample size was 300, calculated with 95% confidence interval, 10% margin of error and 5% level of significance. It was done by using formula; n=Zs (p)(1-p)/d2 by using consecutive, non-probability sampling technique. After IRB approval all neonates meeting the inclusion criteria were included in the study after seeking informed consent from parents and relevant data was collected on the predesigned proforma. Results: Among 300 neonates included in final study 42% had mild hyponatremia and 58% had moderate-severe hyponatremia. Risk of severe hyponatremia were GA 28-32+⁶ weeks, IUGR and APGAR-5<7. PIH increased the risk of chronic hyponatremia. Conclusion: In our study population 58% neonates had moderate to severe hyponatremia. Among 73.1% neonates born at GA 28-32⁺⁶ had moderate to severe hyponatremia. APGAR-5 of <7 and IUGR increases the risk of moderate-severe hyponatremia by 42374 and 200 times respectively. Whereas maternal PIH is associated with increased risk of chronic hyponatremia.