When a newborn undergoes phototherapy, what organs must be protected and why?

Mostly the eyes : Side effect from the phototherapy can be a possible retinal damage. Body termoregulation and proper hydration should be following as well. With the light sources including uv lights in the past - genitalia coverage was also in a list (possible increased incidence in the testicular tumor), but not in the current phototherapy practice for the infantile jaundice treatment.

The eyes: Phototherapy is treatment for hyperbilirubinemia. When baby is inside has lots of red blood cells, these tend to breakdown once baby is born these breakdown to bilirubin and cause yellowing. This can be normal but if levels are high they can affect the brain, so photo protects the brain. Risks are minimal but there is theoretical risk to the eyes, so a mask is used to cover. Other skin exposed.