Special anaesthesia: right-to-left shunt: 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.

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Anaesthesia · Special anaesthesia: right-to-left shunt

Sample item

A child with a cyanotic congenital heart lesion and a right-to-left shunt needs an intravenous line for a minor procedure. Which precaution is specifically important?

AUse rapid boluses to flush all linesBUse only dextrose-containing fluidsCAvoid the use of any intravenous accessDRemove all air bubbles from intravenous lines, or use air filters

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

The answer and the reasoning

D. Remove all air bubbles from intravenous lines, or use air filters

With a right-to-left shunt, venous bubbles can bypass the lungs and enter the systemic circulation, causing paradoxical air embolism to the brain or heart. Meticulous de-airing of lines and air filters are standard precautions. Maintaining systemic vascular resistance is also important to avoid increasing the shunt.

Option by option

A. Use rapid boluses to flush all lines
Rapid boluses can push air or particles across the shunt.
B. Use only dextrose-containing fluids
The type of fluid does not address the risk of paradoxical embolism.
C. Avoid the use of any intravenous access
Intravenous access is usually required and can be used safely with precautions.
D. Remove all air bubbles from intravenous lines, or use air filters (correct)
Correct. Any air in the venous system can reach the systemic circulation through the shunt.

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 D, Remove all air bubbles from intravenous lines, or use air filters. With a right-to-left shunt, venous bubbles can bypass the lungs and enter the systemic circulation, causing paradoxical air embolism to the brain or heart.

Why is "Use rapid boluses to flush all lines" not the answer?

Rapid boluses can push air or particles across the shunt.

Why is "Use only dextrose-containing fluids" not the answer?

The type of fluid does not address the risk of paradoxical embolism.

Why is "Avoid the use of any intravenous access" not the answer?

Intravenous access is usually required and can be used safely with precautions.

What concept does this question test?

It tests Special anaesthesia: right-to-left shunt in Anaesthesia. Meticulous de-airing of lines and air filters are standard precautions. Maintaining systemic vascular resistance is also important to avoid increasing the shunt.

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 Special anaesthesia: right-to-left shunt?

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.