Endogenous hydroperoxides alone may overwhelm defenses. The addition of hyperperoxides from light-exposed TPN or fat emulsions increases the risk of tissue damage. Hydroperoxides have been associated with hypoxic-ischemic encephalopathy, intraventricular hemorrhage, periventricular leukomalacia, chronic lung disease, retinopathy of prematurity, and necrotizing enterocolitis. By protecting these infusates from light, bedside nurses can reduce the amount of hydroperoxides infused and protect NICU patients from the associated risks. It is a functional rather than mechanical obstruction, characterized by the absence of intrinsic ganglion cells in the myenteric and submucosal plexuses of the bowel wall.
Ganglion cells regulate normal colonic peristaltic activity.
Paucity of ganglion cells results in an aganglionic segment of bowel that is functionally abnormal and does not propagate the normal peristaltic wave that moves to it from the proximal ganglionic bowel. The lesion originates in the rectum and extends proximally over a variable distance of the bowel. The further the lesion extends, the more difficult the management becomes. Clinical and radiologic findings can be useful in diagnosis, but they are not pathognomonic. The definitive diagnosis is made following suction biopsy of the rectum, colon, and ileum.