Which of the following drugs is withheld if the patient's pulse is less than 60/min?

Appeared in: AIIMS Raipur - 2017 (Shift-3)

Explanation

Digoxin is a cardiac glycoside that has a negative chronotropic effect, meaning it slows down the heart rate.
A key nursing responsibility and safety protocol is to check the apical pulse for a full minute before administration.
If an adult patient's pulse is below 60 beats per minute, the medication is withheld to prevent severe bradycardia or heart block.
This drug increases the force of contraction while slowing the heart, making it effective for heart failure but risky in bradycardic patients.

Option B: Dobutamine is a sympathomimetic drug that stimulates beta-1 adrenergic receptors, leading to an increase in heart rate and contractility.
Option C: Dopamine is a vasopressor and inotrope that, depending on the dose, increases heart rate, contractility, and blood pressure.
Option D: Phenytoin is an anticonvulsant medication used to treat seizures. Its primary action is on the central nervous system, not directly on heart rate regulation in this manner.

Clinical Relevance

Nursing practice connection: Knowing Pharmacology: Contraindications for Cardiac Medications helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Patient safety is paramount. The pre-administration check of the apical pulse for Digoxin is a non-negotiable nursing action to prevent life-threatening adverse effects.
Nurses must educate patients and their families on how to monitor their pulse at home and to recognize and report signs of Digoxin toxicity, such as loss of appetite, nausea, vomiting, confusion, or vision changes (e.g., seeing yellow-green halos).
What if? If the patient's serum potassium level is low (hypokalemia), the risk of Digoxin toxicity increases significantly, even with a normal drug level. Therefore, monitoring electrolytes is another crucial nursing responsibility.

How to Approach the Question

First, identify the core of the question: it asks for a specific contraindication (pulse less than 60/min) for a medication.
This is a factual recall question from pharmacology. Access your knowledge of common cardiac medications.
Consider each option's drug class and primary effect. Digoxin is a cardiac glycoside known for slowing the heart rate.
Evaluate the other options. Dobutamine and Dopamine are inotropes that typically increase heart rate.
Phenytoin is an anticonvulsant, making it the least likely candidate related to a specific heart rate parameter for routine administration.
Conclude that Digoxin is the only drug on the list for which a pulse rate below 60/min is a standard reason to withhold the dose.

Concept Tested & Keywords

Q7koL34M77eRx518NlipuG

E6 Nursing Brunner Adult Health 3SA Vol 1 Part 3 p. 34-36

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 690-692

E6 Pharmacology Katzung 16e p. 335-337

Practise the full AIIMS Raipur - 2017 (Shift-3)

Attempt every question from this paper in a timed mock, then review the full solution for each one.