Local anesthetic systemic toxicity: 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 anesthetic systemic toxicity

Sample item

Minutes after a large-volume brachial plexus block with bupivacaine, a patient complains of circumoral numbness, tinnitus and a metallic taste. She then has a generalised seizure, followed by wide-complex bradycardia and hypotension. What is the most likely diagnosis?

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

The answer and the reasoning

B. Local anaesthetic systemic toxicity

Intravascular uptake or injection of local anaesthetic gives early CNS excitation (perioral numbness, tinnitus, metallic taste, seizures) followed by CNS depression and cardiovascular collapse. Bupivacaine is especially cardiotoxic. Treatment is airway support, seizure control, advanced life support with reduced adrenaline and 20% lipid emulsion.

Option by option

  • A. Total spinal block

    A total spinal follows a neuraxial injection and causes apnoea and hypotension without the preceding sensory symptoms.

  • B. Local anaesthetic systemic toxicity (correct)

    Correct. The sequence from CNS excitation to arrhythmia after a large block is typical.

  • C. Vasovagal syncope

    Vasovagal syncope gives transient faintness and does not cause seizures or wide-complex rhythm.

  • D. Anaphylaxis to the drug

    Anaphylaxis causes urticaria, bronchospasm and hypotension and does not produce circumoral paraesthesia.

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.

More Anaesthesia questions

Questions about this Anaesthesia question

What is the answer to this Anaesthesia question?

The best answer is B, Local anaesthetic systemic toxicity. Intravascular uptake or injection of local anaesthetic gives early CNS excitation (perioral numbness, tinnitus, metallic taste, seizures) followed by CNS depression and cardiovascular collapse.

Why is "Total spinal block" not the answer?

A total spinal follows a neuraxial injection and causes apnoea and hypotension without the preceding sensory symptoms.

Why is "Vasovagal syncope" not the answer?

Vasovagal syncope gives transient faintness and does not cause seizures or wide-complex rhythm.

Why is "Anaphylaxis to the drug" not the answer?

Anaphylaxis causes urticaria, bronchospasm and hypotension and does not produce circumoral paraesthesia.

What concept does this question test?

It tests Local anesthetic systemic toxicity in Anaesthesia. Bupivacaine is especially cardiotoxic. Treatment is airway support, seizure control, advanced life support with reduced adrenaline and 20% lipid emulsion.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. 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 anesthetic systemic toxicity?

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.