Filtered sunlight is a cheap, effective way to treat infant jaundice, according to a study by Stanford researchers.
The Stanford team, whose work was published in The New England Journal of Medicine, tested whether real sunlight —which is plentiful at many hospitals in tropical climes — could be made safe enough for babies to lie in for hours a day.
They enrolled 447 neonates born at the Island Maternity Hospital in Lagos, Nigeria, who developed jaundice within the first 14 days of life (none had severe hyperbilirubinemia).
223 received sunlamp phototherapy, and 224 slept in outdoor cribs or their mothers’ laps under canopies of plastic film that filtered out ultraviolet and infrared rays.
Filtered sunlight phototherapy (FS-PT) was improvised using a metal frame covered with commercial plastic sun-control film costing approximately $300. The Air Blue 80 film (CP Films, Fieldale, VA) transmitted 79% of blue light and was used on cloudy days, while the Gila Titanium (CP Films, Inc) that allowed 33% of blue wavelength light was used on sunny days. Both films cut out most of the harmful UV radiation.
To prevent the infants in the sunlight group from overheating, they were wrapped in wet towels if their body temperature was higher than 37.5°C. If an infant's temperature went higher than 38°C, the mother brought the infant out of the sun to a shaded area. No infants met the criteria for study withdrawal, which included temperature higher than 38°C for an hour or more or requiring treatment for sunburn or dehydration.
At the end of the study, the sunlight treatment was slightly more effective than phototherapy and the children did not have more sunburn, dehydration or overheating.
"Existing guidelines for managing neonatal hyperbilirubinemia do not recommend — and some explicitly discourage — the use of sunlight for the treatment of neonatal hyperbilirubinemia," the authors wrote, because of concerns about ultraviolet and infrared exposure, hyperthermia, and sunburn.
Given the positive results of the trial, the authors recommended: “Caregivers should therefore be educated on the essential differences between filtered sunlight. and direct exposure to sunlight.”