Phototherapy induced electrolyte imbalance in hyperbilirubinemia of newborns

Neonatal Hyperbilirubinemia (NH) is the commonest abnormal physical finding during the first week of life. Neonatal Hyperbilirubinemia (NH) is the most common cause for readmission during the early neonatal period and is a cause of concern for the parents as well as for the pediatricians. Hence appropriate management of Neonatal Hyperbilirubinemia is of paramount importance. Phototherapy plays a significant role in prevention and treatment of hyperbilirubinemia. However, this treatment modality may itself result in inherent complications.
Objective: To evaluate the electrolyte changes in neonates receiving phototherapy for neonatal hyperbilirubinemia.
Method: A prospective hospital based observational comparative study conducted on 252 eligible neonates admitted in the Neonatal Intensive Care Unit receiving phototherapy at a teaching Hospital AJIMS,MANGALORE from June 1st 2017 to october 31st 2017. A predesigned proforma has aided the enrollment of newborns into the study according to AAP guidelines. Serum bilirubin and electrolytes were determined before and after termination of phototherapy. The first samples were considered as controls. A comparative study was made between before and after phototherapy groups to determine the incidence of electrolyte changes.
Results: The study group included 252 neonates that were managed with phototherapy. Male: Female ratio was 1.45:1. Incidence of low birth weight babies was 23% and preterm was 20.2%. Mean birth weight and gestational age was 2.84±0.51 kg and 38.44±1.98 weeks respectively. Mean duration of phototherapy was 37.65±11.06hrs. The incidence of hypocalcemia post phototherapy found to be 13.1% (p=0.013) which was more in LBW babies (36.2%, p<0.001) and preterm neonates (41.2%, p<0.001) than in normal weight babies (6.2%) and term neonates (6.2%) and 18.8% when duration of phototherapy was >48hrs (p<0.001). The incidence of hyponatremia post phototherapy found to be 6% which was more in LBW babies (17.2%, p<0.001) and preterm neonates (17.6%, p<0.001) than in normal weight babies (2.6%) and term neonates (3.1%) and 17.4% when duration of phototherapy was >48hrs (p<0.001). Even the decline in mean serum calcium and sodium values found to be statistically significant. None of the hypocalcemic neonates were symptomatic clinically. The incidence of potassium and chloride changes following phototherapy was found to be non-significant irrespective of gestational age, birth weight and duration of phototherapy.
Conclusion: The study shows that neonates undergoing phototherapy are at a higher risk of electrolyte changes. This risk is greater in premature and LBW babies and hence this group of babies should be closely monitored for changes in electrolytes and should be managed accordingly.