Phototherapy and serum blood calcium levels in neonates: is there a need for calcium supplementation?

Background: Phototherapy is the first line of treatment for physiological jaundice. However, it has its own set of complications. Hypocalcaemia is a less frequent but a potential complication of phototherapy. The purpose of this study was to see the effect of 24 hours of phototherapy on the serum blood calcium levels of the newborn after 24 hours of exposure and the need for supplementation in these new born babies. Methods: A cross sectional observational study was conducted at our institute on 31 newborn babies born between June 2022 to December 2022. All term neonates who developed clinically significant physiological jaundice after 48 hours of life were subjected to double surface phototherapy with LED blue light for 24 hours. These babies were screened for their serum calcium levels by venous blood sampling before the commencement of the phototherapy. The same sampling was repeated after 24 hours of exposure to the phototherapy lights to see the effect on serum calcium levels of the newborn. Results: Phototherapy was given for 24 hours. Mean serum calcium measured at 48 hours of life prior to phototherapy was 9.25±0.62 mg/ml. Also, mean serum calcium at 24 hours post phototherapy was 8.74±0.38 mg/ml. A highly significant decrease in serum calcium level was seen post phototherapy (p=0.0002). Independent samples t test was used. Conclusions: In healthy term neonates exposed for only 24 hours of phototherapy decrease in serum calcium levels to some extend was noted however it is unlikely to cause clinically significant hypocalcemia.