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Ultrasound resolution — FRCA Primary MCQ

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HardPhysicsUltrasound resolutionFRCA Primary

In monopolar diathermy, why is a large return electrode placed in broad contact with the patient?

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Correct answer: D — To disperse return current and reduce skin thermal injury

The best answer is “To disperse return current and reduce skin thermal injury”. The return electrode disperses current over a large area, reducing current density and the risk of a return-site burn. It does not create the cutting effect, rectify the current, replace electrical isolation, or eliminate all electromagnetic interference.

Reference: RCoA, Primary FRCA Syllabus: https://rcoa.ac.uk/sites/default/files/documents/2026-01/Primary-FRCA-Syllabus.pdf