A client who is receiving magnesium sulfate has a urine output of 20 mL/hr. Which of the following medications should the nurse expect to administer?

Choice A reason: Naloxone is not the correct medication. Naloxone is an opioid antagonist that reverses the effects of opioid overdose, such as respiratory depression, sedation, and hypotension. Naloxone has no effect on magnesium sulfate, which is a mineral and electrolyte that is used to prevent seizures in clients with preeclampsia or eclampsia.

Choice B reason: Protamine is not the correct medication. Protamine is a heparin antagonist that reverses the effects of heparin overdose, such as bleeding, bruising, and thrombocytopenia. Protamine has no effect on magnesium sulfate, which is not an anticoagulant.

Choice C reason: Calcium gluconate is the correct medication. Calcium gluconate is a calcium salt that antagonizes the effects of magnesium sulfate overdose, such as hypotension, bradycardia, respiratory depression, and muscle weakness. Calcium gluconate is the antidote for magnesium sulfate toxicity, which can occur when the serum magnesium level is above 7.5 mEq/L. The nurse should monitor the client's vital signs, deep tendon reflexes, and urine output, and report any signs of toxicity to the provider.

Choice D reason: Flumazenil is not the correct medication. Flumazenil is a benzodiazepine antagonist that reverses the effects of benzodiazepine overdose, such as drowsiness, confusion, and coma. Flumazenil has no effect on magnesium sulfate, which is not a sedative.

Choice A reason: Using IV tubing specific for heparin sodium when administering the infusion is not the correct action. Heparin sodium can be administered using any standard IV tubing, as long as it is primed with heparin solution to prevent clotting in the tubing.

Choice B reason: Administering 50,000 units of heparin by IV bolus every 12 hours is not the correct action. This is a very high dose of heparin that can cause bleeding complications. The usual dose of heparin for continuous IV infusion is 15 to 25 units/kg/hour, adjusted according to the aPTT results.

Choice C reason: Having vitamin K available on the nursing unit is not the correct action. Vitamin K is the antidote for warfarin, not heparin. Vitamin K reverses the effects of warfarin by increasing the synthesis of clotting factors in the liver.

Choice D reason: Checking the activated partial thromboplastin time (aPTT) every 4 hours is the correct action. The aPTT is a blood test that measures the time it takes for the blood to clot. It is used to monitor the effectiveness and safety of heparin therapy. The therapeutic range of aPTT for heparin is 1.5 to 2.5 times the normal value, or 60 to 80 seconds. The nurse should check the aPTT every 4 hours until it is within the therapeutic range, and then every 6 to 8 hours thereafter. The nurse should adjust the heparin infusion rate according to the aPTT results and the prescriber's orders.