Neonatal Nurse Practitioner Practice Exam

What is the best predictor of bilirubin toxicity in neonates?

1. Bilirubin-albumin ratio

2. Total serum bilirubin concentration

3. Hearing impairment

4. Liver function tests

The correct answer is: Hearing impairment

The best predictor of bilirubin toxicity in neonates is the bilirubin-albumin ratio. This ratio provides valuable insight into the risk of bilirubin crossing the blood-brain barrier and causing toxicity, such as kernicterus. A high total serum bilirubin concentration alone does not fully convey the risk of toxicity because it is essential to consider the binding of bilirubin to albumin. If bilirubin levels are elevated, but they are still adequately bound to albumin, the risk of toxic effects is reduced. While hearing impairment can occur as a result of bilirubin toxicity, it is often a consequence rather than a predictor. Liver function tests can give useful information about liver health but do not directly correlate with the risk of bilirubin toxicity. Thus, understanding how bilirubin binding to albumin influences toxicity is crucial in neonatal care, solidifying the importance of the bilirubin-albumin ratio as the most direct predictor for the risk of bilirubin-induced neurological damage.