Final answer:
Immediate intervention from the nurse is required if a 38-weeks pregnant woman receiving magnesium sulfate for preeclampsia shows brisk and hyperactive Deep tendon reflexes (DTRs), which could indicate magnesium toxicity.
Step-by-step explanation:
A woman who is 38-weeks gestation receiving magnesium sulfate for severe preeclampsia requires immediate intervention from the nurse if she exhibits Deep tendon reflexes (DTRs) brisk and hyperactive. This could indicate magnesium toxicity, which is a serious complication. While a blood pressure of 150/100 mmHg is high and indicative of the ongoing preeclampsia, it is not as immediately life-threatening as potential magnesium toxicity. A respiratory rate of 18 breaths per minute is within normal range and a urinary output of 50 mL/hour meets the minimum expected output for a patient receiving magnesium sulfate therapy (30 mL/hour).