[Chap 25] Class IV Antidysrhythmic Drugs (Calcium Channel Blockers)
Which statements are most appropriate when teaching about the management of calcium channel blockers' side effects?
"Drink up to 8 glasses of water to avoid constipation."
When administering oral diltiazem to a patient, the nurse would expect to note a therapeutic response in what time frame?
1-3 hours
Which are common adverse reactions related to calcium channel blockers?
Ankle edema Constipation Facial flushing
A patient asks the nurse what diltiazem is prescribed for. The nurse responds that diltiazem is indicated for treatment of which dysrhythmia?
Atrial fibrillation Supraventricular tachycardia Atrial flutter
How do calcium channel blockers inhibit the transport of calcium in the heart?
Calcium channel blockers are calcium ion channel antagonists, which prevent calcium from entering cells of the heart and blood vessel walls.
Mr. Allen is going to be discharged with oral verapamil. What should the nurse teach him about this medication?
Check his pulse before taking verapamil. Do not drink grapefruit juice while taking verapamil. Constipation is a common side effect of verapamil.
Which statement(s) correctly explain why the nurse should closely monitor the liver status of an 80 year-old patient on diltiazem?
Diltiazem dose would need to be reduced in a patient with hepatic impairment
A patient taking diltiazem and digoxin has elevated digoxin levels and missed her appointment to obtain lab draws. How should interactions between the two drugs be explained and the rationale for monitoring blood levels?
Diltiazem may cause a significant increase in the serum concentration of digoxin.
Upon discharge from the hospital, a patient is ordered to take a calcium channel blocker in a sustained-release form. What teaching should be included for this patient?
Do not split or crush or chew a sustained-release formulation. A wax matrix may be visible in your stool. Monitor your heart rate and blood pressure and report a slow heart rate and low blood pressure to your health care provider.
A health care provider routinely orders verapamil 360 mg per day in divided doses for the prevention of paroxysmal supraventricular tachycardia. Why would the nurse question this order for a patient with a history of liver cirrhosis?
Doses of verapamil must be substantially reduced in patients with hepatic impairment.
Why do most calcium channel blockers have low and variable oral bioavailability?
Due to extensive first-pass metabolism in the liver.
Patients taking calcium channel blockers should be instructed to avoid which beverages?
Grapefruit juice Alcoholic beverages Caffeinated beverages
The nurse confirms Mr. Allen's heart rate is 56. What action should the nurse take with regard to the administration of verapamil? CASE STUDY DETAILS
Hold the medication and contact the prescriber.
A patient with new-onset atrial fibrillation receives diltiazem intravenously. How does diltiazem temporarily slow the ventricular response to atrial fibrillation?
It slows the conduction of impulses through the AV node.
Verapamil is contraindicated for a patient with sick sinus syndrome. Which statements most accurately describe a potential adverse effect of verapamil on the sinoatrial node of the heart?
May interfere with sinus-node impulse generation.
What are the routes of administration for diltiazem?
Oral Intravenous
What are the routes of administration for verapamil?
Oral Intravenous
Which symptoms should patients on calcium channel blockers be instructed to report to their health care provider?
Pronounced dizziness Edema Shortness of breath
Which is appropriate treatment for calcium channel blocker overdose?
Secure patient's airway; administer fluids and norepinephrine; administer intravenous atropine or glucagon; administer intravenous calcium
A patient with paroxysmal supraventricular tachycardia is to receive 5mg of verapamil intravenously. How does the nurse administer the dose?
Slow injection
Blockade of calcium channels by verapamil and diltiazem include which effects on cardiac tissue?
Slowing of sinoatrial (SA) node automaticity Delay of atrioventricular (AV) nodal conduction Reduction of myocardial contractility
For which condition are the most common calcium channel blockers verapamil and diltiazem used?
Supraventricular tachyarrhythmias
Calcium channel blockers are used to treat which cardiovascular condition?
Supraventricular tachycardia
A patient taking diltiazem is complaining of dizziness. What should the assessment of this patient include?
The patient history regarding postural changes The patient's blood pressure A 12-lead ECG The patient's food and drug history
For which reasons would a nurse withhold a scheduled dose of diltiazem (Cardizem) or verapamil (Calan)?
Third-degree AV block Severe hypotension
Calcium channel blockers are contraindicated for patients with which conditions?
Third-degree heart block Sick-sinus syndrome
