A nurse is caring for a client who has hypertension and asks the nurse about a prescription for propranolol. The nurse should inform the client that this medication is contraindicated in clients who have a history of which of the following conditions?

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.

Choice A reason: Taking only one dose of nitroglycerin is not a good advice, as it may not be enough to relieve the angina pain and prevent a myocardial infarction. Nitroglycerin is a vasodilator that relaxes the blood vessels and improves the blood flow to the heart. The recommended dose is one tablet or spray under the tongue every 5 minutes for up to three doses, or until the pain is relieved. Taking only one dose may compromise the effectiveness of the medication and the safety of the client.

Choice B reason: Asking the provider to prescribe a different medication is not a necessary action, as nitroglycerin is a first-line treatment for stable angina and has proven benefits for reducing mortality and morbidity. Changing the medication may not be appropriate or feasible, as there may not be a suitable alternative that has the same efficacy and safety profile. The client should continue taking nitroglycerin as prescribed, unless the provider decides otherwise.

Choice C reason: Saying that there's nothing that can be done to relieve the headaches is not a true or helpful statement, as there are some measures that can help reduce or prevent the headaches. Headaches are a common and expected side effect of nitroglycerin, as it dilates the blood vessels in the brain and causes increased intracranial pressure. However, the headaches usually subside over time as the body adapts to the medication. The client can also take a mild analgesic, such as acetaminophen or ibuprofen, to relieve the headache, as long as it does not interact with the nitroglycerin or other medications.

Choice D reason: Trying to take a mild analgesic to relieve the headache is a reasonable and appropriate suggestion, as it can help alleviate the discomfort and improve the quality of life of the client. The client should choose an analgesic that is safe and effective, such as acetaminophen or ibuprofen, and follow the directions on the label. The client should also consult the provider or the pharmacist before taking any over-the-counter medications, as some of them may interact with nitroglycerin or other medications. The client should also avoid aspirin, as it may increase the risk of bleeding.