Clinical results of a new, high phototherapeutic efficiency blue-green lamp for the management of hyperbilirubinemia

We report a preliminary study on the introduction of a new, blue-green fluorescent lamp with high phototherapeutic efficiency in the treatment of neonatal hyperbilirubinemia. The lamp (New Lamp) has an emission spectrum, peaked at 490 nm and about 40 nm wide, that was not previously investigated in clinical trials. Our study demonstrates the significantly greater efficacy of the New Lamp in decreasing the bilirubin serum level, in comparison with the most commonly used blue fluorescent lamp. The rate of decline of bilirubin concentration with the New Lamp was twice that with Philips/BB light. The success of the blue-green PT is mainly due to the combined effects of the (1) increase from blue to green of the quantum yield for lumirubin, that is the bilirubin photoproduct rapidly excreted from the organism; (2) corresponding decrease of the configurational photoisomer, formed with high concentration but not excreted from the organism; (3) filtering effect of the skin, which attenuates more blue than green light. Our results represent the first significant improvement of phototherapy efficiency following the development and introduction of the special-blue lamp by Sisson in 1970. The phototherapy exposure time has now been reduced to less than 1-day in preterm infants, ensuring less stress to the infant and less interference with nursing care.