A nurse is assisting in the care of a client who is to undergo an amniotomy. Which of the following is the priority nursing action following this procedure?

Choice A rationale:

Excessive uterine enlargement. Rationale: The nurse should monitor the client for excessive uterine enlargement, as a hydatidiform mole is a rare condition in pregnancy where abnormal placental tissue forms instead of a fetus. This abnormal growth can lead to uterine enlargement beyond the expected size for gestational age.

Choice B rationale:

Rapidly dropping human chorionic gonadotropin (hCG) levels. Rationale: The nurse should also monitor the client's hCG levels. In a normal pregnancy, hCG levels typically rise steadily during the early stages. However, in the case of a hydatidiform mole, hCG levels may either plateau or drop rapidly due to the abnormal placental growth.

Choice C rationale:

Fetal heart rate irregularities. Rationale: Although a hydatidiform mole does not involve a viable fetus, the nurse should still assess for fetal heart rate irregularities. In some rare cases, the presence of abnormal placental tissue can cause confusion in the diagnosis, and there may be coexisting fetal development. Fetal heart rate irregularities may indicate potential complications.

Choice D rationale:

Whitish vaginal discharge. Rationale: Whitish vaginal discharge is not typically associated with a hydatidiform mole. Instead, this finding is more commonly seen in other vaginal infections or conditions unrelated to a molar pregnancy. The nurse should be cautious not to misinterpret this symptom as a definitive sign of a hydatidiform mole.

The correct answer is choice A: Respiratory rate of 16/min.

Choice A rationale:

A respiratory rate of 16/min is within the normal range for adults, which is typically between 12 to 20 breaths per minute. In the context of severe preeclampsia, maintaining a normal respiratory rate is crucial when administering magnesium sulfate IV, as one of the signs of magnesium toxicity is respiratory depression. Therefore, a respiratory rate of 16/min indicates that the client is not experiencing respiratory depression and it is safe to continue the magnesium sulfate infusion.

Choice B rationale:

A heart rate of 60/min is at the lower end of the normal range, which is 60 to 100 beats per minute for adults. However, bradycardia or a low heart rate can be a sign of magnesium sulfate toxicity, especially if accompanied by other symptoms such as hypotension or altered mental status. Without additional context, a heart rate of 60/min alone does not necessarily indicate it is unsafe to continue the infusion, but it would require further assessment.

Choice C rationale:

A urine output of 50 mL in 4 hours is significantly below the expected minimum of 30 mL/hour for adults. Adequate urine output is an important indicator of kidney function and is essential for the excretion of magnesium. In the case of magnesium sulfate infusion for severe preeclampsia, a low urine output could indicate renal insufficiency and an increased risk of magnesium toxicity. Therefore, a urine output of 50 mL in 4 hours is a contraindication for continuing the infusion without further evaluation.

Choice D rationale:

Diminished deep-tendon reflexes can be a sign of magnesium toxicity. Deep-tendon reflexes are assessed to monitor for signs of magnesium overdose during infusion, as magnesium acts as a central nervous system depressant at high levels. If deep-tendon reflexes are diminished, it may suggest that the serum magnesium levels are too high, and the infusion should be paused or discontinued to prevent further toxicity.

In summary, the only finding that clearly indicates it is safe to continue the magnesium sulfate infusion is a normal respiratory rate, as provided in choice A. The other options either require further assessment or are indicators of potential magnesium toxicity.