Local anaesthetics: bupivacaine cardiotoxicity: practice question

A Anaesthesia question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Anaesthesia · Local anaesthetics: bupivacaine cardiotoxicity

Sample item

Why is cardiac arrest from bupivacaine particularly difficult to treat?

AIt stimulates catecholamine releaseBIt dissociates slowly from cardiac sodium channels, producing refractory ventricular arrhythmiasCIt inhibits cholinesteraseDIt causes complete heart block only

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. It dissociates slowly from cardiac sodium channels, producing refractory ventricular arrhythmias

Bupivacaine is highly lipophilic and protein bound and its slow dissociation (fast-in slow-out) causes re-entrant arrhythmias and severe myocardial depression. The 0.75% concentration is contraindicated in obstetrics.

Option by option

A. It stimulates catecholamine release
It does not stimulate catecholamine release.
B. It dissociates slowly from cardiac sodium channels, producing refractory ventricular arrhythmias (correct)
Correct. Slow dissociation causes refractory arrhythmias.
C. It inhibits cholinesterase
It does not inhibit cholinesterase.
D. It causes complete heart block only
It causes more than heart block.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Anaesthesia question

What is the answer to this Anaesthesia question?

The best answer is B, It dissociates slowly from cardiac sodium channels, producing refractory ventricular arrhythmias. Bupivacaine is highly lipophilic and protein bound and its slow dissociation (fast-in slow-out) causes re-entrant arrhythmias and severe myocardial depression.

Why is "It stimulates catecholamine release" not the answer?

It does not stimulate catecholamine release.

Why is "It inhibits cholinesterase" not the answer?

It does not inhibit cholinesterase.

Why is "It causes complete heart block only" not the answer?

It causes more than heart block.

What concept does this question test?

It tests Local anaesthetics: bupivacaine cardiotoxicity in Anaesthesia. The 0.75% concentration is contraindicated in obstetrics.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Local anaesthetics: bupivacaine cardiotoxicity?

Make a table of each agent, its key advantage and its main side effect. Then use the flashcards and the other Anaesthesia questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.