A nurse is administering magnesium sulfate IV to a client who has severe preeclampsia.

Which of the following assessments should the nurse perform to monitor for magnesium toxicity? Select all that apply.

“You may feel warm and flushed while receiving this medication.” This is a common side effect of magnesium sulfate therapy, which is used to prevent seizures in women with severe pre-eclampsia.Magnesium sulfate can also help prolong a pregnancy for up to two days by relaxing the uterus.

Choice B is wrong because magnesium sulfate can cause fluid retention and swelling, not dehydration.Choice C is wrong because magnesium sulfate can cause drowsiness and lethargy, not insomnia and restlessness.Choice D is wrong because magnesium sulfate can cause decreased blood pressure and heart rate, not inflammation and infection at the infusion site.

Normal ranges for blood pressure are below 140/90 mm Hg, for platelet count are 150,000 to 450,000 per microliter of blood, and for protein in urine are less than 300 milligrams per day.

The client has no seizures or eclampsia.This outcome would indicate that the magnesium sulfate therapy is successful because magnesium sulfate is a mineral that reduces seizure risks in women with preeclampsia.

Some additional information for the other choices are:

• Choice B. The client delivers a healthy baby vaginally.

This outcome is desirable but not directly related to the effectiveness of magnesium sulfate therapy.Magnesium sulfate can help prolong a pregnancy for up to two days to allow drugs that speed up the baby’s lung development to be administered, but it does not guarantee a vaginal delivery or a healthy baby.

• Choice C. The client has normal blood pressure and urine output.

This outcome is also desirable but not directly related to the effectiveness of magnesium sulfate therapy.

Magnesium sulfate may help reduce blood pressure in some cases, but it is not the primary treatment for hypertension in preeclampsia.Other medications such as antihypertensives are usually prescribed for that purpose.Urine output should be monitored closely while receiving magnesium sulfate therapy, as a decrease may indicate toxicity or kidney impairment.Urine output should be at least 30 mL/hour while administering magnesium sulfate.

• Choice D. The client has improved liver function and platelet count.

This outcome is also desirable but not directly related to the effectiveness of magnesium sulfate therapy.

Magnesium sulfate does not affect liver function or platelet count in preeclampsia.These parameters may improve after delivery of the placenta, which is the main cause of preeclampsia.

Normal ranges for blood pressure, urine output, liver function and platelet count are:

• Blood pressure: less than 140/90 mm Hg

• Urine output: at least 30 mL/hour

• Liver function: AST and ALT less than 40 U/L, LDH less than 600 U/L, bilirubin less than 1.2 mg/dL

• Platelet count: 150,000 to 450,000 per microliter of blood