Electrolytes: practice question

A General Medicine 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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General Medicine · Electrolytes

Sample item

A patient with end-stage kidney disease who missed dialysis has potassium of 7.2 mmol/L, peaked T waves and a widened QRS. Which drug is given first?

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

The answer and the reasoning

A. Intravenous calcium gluconate

With ECG changes, hyperkalaemia is life-threatening and the first priority is to protect the myocardium. Intravenous calcium stabilises the cardiac membrane within minutes without lowering potassium, and insulin-dextrose, salbutamol and dialysis then remove or shift the potassium.

Option by option

  • A. Intravenous calcium gluconate (correct)

    Correct. Calcium antagonises the membrane effects and prevents arrhythmia.

  • B. Intravenous insulin with dextrose

    Insulin with dextrose shifts potassium into cells but does not stabilise the membrane and is given after calcium.

  • C. Oral sodium polystyrene resin

    Resins remove potassium slowly over hours and are too slow for an emergency.

  • D. Nebulised salbutamol

    Salbutamol shifts potassium modestly and is an adjunct, not the first protective step.

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 General Medicine questions

Questions about this General Medicine question

What is the answer to this General Medicine question?

The best answer is A, Intravenous calcium gluconate. With ECG changes, hyperkalaemia is life-threatening and the first priority is to protect the myocardium.

Why is "Intravenous insulin with dextrose" not the answer?

Insulin with dextrose shifts potassium into cells but does not stabilise the membrane and is given after calcium.

Why is "Oral sodium polystyrene resin" not the answer?

Resins remove potassium slowly over hours and are too slow for an emergency.

Why is "Nebulised salbutamol" not the answer?

Salbutamol shifts potassium modestly and is an adjunct, not the first protective step.

What concept does this question test?

It tests Electrolytes in General Medicine. Intravenous calcium stabilises the cardiac membrane within minutes without lowering potassium, and insulin-dextrose, salbutamol and dialysis then remove or shift the potassium.

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 Electrolytes?

For each disease know the classic presentation, the best test, and the first-line treatment. Then use the flashcards and the other General Medicine 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.