BACKGROUND: Phototherapy is the primary treatment for hyperbilirubinemia in neonates. Hypocalcemia is a lesser known but potential detrimental effect of phototherapy. It has been hypothesized that phototherapy inhibits pineal secretion of melatonin, which blocks the effect of cortisol on bone calcium. Therefore, unchecked cortisol increases bone uptake of calcium and induces hypocalcemia. Covering head during phototherapy in order to prevent light reaching to the pineal gland which eventually leads to the prevention of hypocalcemia is hypothesized to prevent hypocalcemia but it lacks sufficient evidence worldwide.
METHOD: It is a prospective, randomized controlled study. 112 neonates were randomized into two groups of 56 neonates. Group A underwent phototherapy without head cover and group B with head covered by a cap.
RESULT: The mean decline in serum ionic calcium after 48 hours of phototherapy in group A and group B was 0.57±0.37 mg/dl and 0.34±0.24 mg/dl respectively. This decline in serum ionic calcium was significantly higher in group A. (p < 0.001). 26.8% newborns from group A developed hypocalcemia while in group B only 14.3% developed hypocalcemia however it was not found to be statistically significant. Incidence of symptomatic hypocalcemia between the two groups was also not significant.
CONCLUSION: There was significant reduction in serum calcium in neonates undergoing phototherapy without head cover as compared to neonates with head cover but risk of hypocalcemia was not significant. Further studies with larger sample size including preterm are recommended.