Effects of Phototherapy on Serum Electrolytes in Neonates Admitted in a Tertiary Care Center, Barabanki

Background: Neonatal jaundice affects over 50% of full-term newborns and is even more common in late-preterm infants. Elevated serum bilirubin levels lead to hyperbilirubinemia, primarily involving unconjugated bilirubin. Phototherapy, particularly using blue light, is the primary treatment to prevent bilirubin-induced neurotoxicity. However, phototherapy's impact on serum electrolytes in neonates remains understudied. Aim: To estimate and compare alterations in serum electrolytes, specifically sodium, calcium, and potassium, in healthy term and late preterm neonates before and after phototherapy. Methods: A prospective observational study was conducted at a tertiary care center over 18 months from 12thJuly 2022 to 12thJanuary 2024. The study included 100 neonates aged, requiring phototherapy for neonatal hyperbilirubinemia. Blood samples were collected before and within 24 hours of stopping phototherapy to measure serum sodium, calcium, and potassium levels using standard laboratory methods. Data were analyzed using SPSS version 21.0, with statistical significance set at p<0.05. Results: The median age at phototherapy initiation was 48 hours. The study included 55 males (55%) and 45 females (45%). The mean birth weight was 2850 grams, 57% were late preterm and 43% term. There was significant decrease in sodium levels post-phototherapy in late preterm neonates and females (p=0.002), significant decrease (p=<0.001) in potassium levels post-phototherapy in both genders, particularly in late preterm neonates, also there is significant decrease in calcium levels post-phototherapy across all categories. Conclusion: Phototherapy significantly reduces serum calcium and alters potassium levels in neonates, while sodium levels remain unaffected. These changes are more prominent in late preterm neonates in comparison to term neonates. These findings highlight the need for careful monitoring of serum electrolytes during phototherapy to manage potential imbalances effectively.