Class IV: Calcium Channel Blockers

Every question here, with the answer

1. A client with atrial fibrillation is due for oral diltiazem. The nurse finds a heart rate of 54 beats per minute and the client has no pacemaker. What should the nurse do?

   1. Give the dose with grapefruit juice.
   2. Give the dose and have the client walk to raise the heart rate.
   3. Give the dose as scheduled.
   4. Check with the health care provider before giving the dose.

   Answer: Check with the health care provider before giving the dose.

   Calcium channel blockers slow the heart rate, so with a baseline rate under 60 and no pacemaker, the nurse checks with the provider first. Giving the dose would slow the rate further, and grapefruit juice should be avoided.

2. A client asks why their blood pressure pill, a DHP calcium channel blocker, will not control their atrial fibrillation. Which explanation is accurate?

   1. DHP calcium channel blockers only work intravenously.
   2. DHP calcium channel blockers act only on arteries, not on the heart.
   3. DHP calcium channel blockers are too weak to work at all.
   4. DHP calcium channel blockers speed up the heart.

   Answer: DHP calcium channel blockers act only on arteries, not on the heart.

   DHP calcium channel blockers block calcium channels only within arteries, so they treat hypertension but not dysrhythmias. The other statements are not supported by the section.

3. A client is admitted and says they take "Cardizem, the long-acting one". What is the nurse's best action?

   1. Substitute any extended-release diltiazem on the unit.
   2. Switch the client to verapamil.
   3. Hold all heart medications until discharge.
   4. Identify the exact product the client takes.

   Answer: Identify the exact product the client takes.

   Oral diltiazem generics are similar but not bioequivalent, so the nurse takes an accurate history of the specific product and avoids confusing them. Substituting, holding everything, or switching drugs are not supported.

4. A nurse reviews the chart of a client prescribed IV diltiazem. Which findings should prompt the nurse to question the order? Select all that apply.

   1. Hypertension
   2. Heart failure with reduced ejection fraction
   3. Atrial fibrillation with rapid ventricular response
   4. Currently receiving a beta-adrenergic blocker
   5. AV block without a pacemaker

   Answer: Heart failure with reduced ejection fraction, Currently receiving a beta-adrenergic blocker, AV block without a pacemaker

   Non-DHP calcium channel blockers reduce contractility and slow conduction, so they are used cautiously or avoided in reduced-ejection-fraction heart failure, AV block without a pacemaker, and with beta blockers. Rapid atrial fibrillation and hypertension are indications.

5. Which teaching points should the nurse include for a client going home on verapamil? Select all that apply.

   1. Stop the medication if the ankles swell a little.
   2. Keep an up-to-date medication list and bring it to appointments.
   3. Report dizziness, lightheadedness or swelling.
   4. Report a racing heart or fatigue.
   5. Avoid drinking grapefruit juice.

   Answer: Keep an up-to-date medication list and bring it to appointments., Report dizziness, lightheadedness or swelling., Report a racing heart or fatigue., Avoid drinking grapefruit juice.

   Clients avoid grapefruit juice, report adverse effects such as dizziness and edema, report signs of therapeutic failure such as a racing heart, and keep a medication list to prevent interactions. Stopping the drug on their own is not in the teaching; edema is reported.

6. A client is receiving an intravenous diltiazem infusion for atrial fibrillation. Which nursing action is required?

   1. Use continuous cardiac and hemodynamic monitoring.
   2. Check the blood glucose every hour.
   3. Monitor only the urine output.
   4. Check vital signs once per shift.

   Answer: Use continuous cardiac and hemodynamic monitoring.

   Clients on intravenous calcium channel blockers need continuous cardiac and hemodynamic monitoring because the drugs lower heart rate and blood pressure. Once-per-shift checks are too infrequent, and glucose or urine output alone do not track these effects.