A nurse is reinforcing teaching with a client who is in labor about why epidural anesthesia is not initiated until a good labor pattern has been established. Which of the following explanations should the nurse include?

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.

Choice A rationale :

Hypercalcemia - The nurse does not need to monitor for hypercalcemia in this scenario. Hypercalcemia refers to high levels of calcium in the blood, and it is not directly related to the newborn's weight or the mother's diabetes mellitus.

Choice B rationale

Hypobilirubinemia - Hypobilirubinemia is low levels of bilirubin in the blood and is not a major concern for a newborn's weight or the mother's diabetes mellitus. Although jaundice (high bilirubin levels) can be a concern in newborns, it is not the focus in this case.

Choice C rationale

Hypoglycemia - This is the correct choice. Newborns of diabetic mothers are at risk of developing hypoglycemia, which is low blood sugar levels. The baby receives excess glucose from the mother during pregnancy, and after birth, insulin production may be higher than needed, leading to low blood sugar levels. Monitoring for hypoglycemia is crucial to prevent potential complications.

Choice D rationale

Decreased RBC - The nurse does not need to monitor for decreased red blood cells (RBC) specifically related to the newborn's weight or the mother's diabetes mellitus. Monitoring RBC levels is important for other conditions, but it is not the primary concern in this case.