Final answer:
While caring for a 2-year-old with Wilms tumor, the nurse must avoid palpating the abdomen to prevent the potential spread of the tumor. Other physical assessment techniques, like checking reflexes or assessing bowel sounds, do not pose a risk and can be conducted safely.
Step-by-step explanation:
When a nurse is caring for a 2-year-old diagnosed with Wilms tumor, a specific physical assessment technique needs to be omitted to prevent potentially spreading the cancer cells. The correct technique to omit is palpating the abdomen. This action should be avoided because it can potentially dislodge cancer cells, which may lead to the spread of the tumor. The other techniques listed, such as performing range-of-motion exercises on lower extremities, assessing for bowel sounds, and percussing ankle and knee reflexes, do not pose the same risk and can be part of the physical assessment.