Final answer:
Before continuing IV magnesium sulfate for preeclampsia, nurses must assess plantar reflexes and urinary output to check for signs of magnesium toxicity and kidney function.
Step-by-step explanation:
The nurse should assess plantar reflexes and urinary output before continuing the administration of IV magnesium sulfate therapy to a client with preeclampsia. Monitoring these two parameters is crucial when administering magnesium sulfate because they help evaluate neuromuscular activity and kidney function, respectively. Deep tendon reflexes, like the plantar reflex, can become diminished or absent if magnesium levels become too high, signaling potential magnesium toxicity. Urinary output is important to monitor as it indicates kidney function and the body's ability to excrete magnesium.