Final answer:
The child at highest risk for cardiac arrest and least likely to be assigned to the nurse reassigned to the pediatric unit is the one with congenital cardiac defects (option A).
Step-by-step explanation:
The child at highest risk for cardiac arrest and least likely to be assigned to the nurse reassigned to the pediatric unit is the one with congenital cardiac defects (option A).
Congenital cardiac defects refer to structural abnormalities in the heart that are present at birth. These defects can lead to compromised cardiac function and increase the risk of cardiac arrest. It requires specialized knowledge and expertise to care for children with cardiac defects, and the nurse from the surgical department may not have the necessary experience in pediatric cardiology.
On the other hand, the other options (B, C, and D) can also pose risks, but they may be more commonly encountered in the pediatric unit and can be managed by a nurse with general pediatric training.