LiDCO Lithium Dilution — FRCA Primary MCQ

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HardPhysics & Clinical MeasurementLiDCO Lithium DilutionFRCA Primary

The LiDCO system measures cardiac output using which indicator?

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Correct answer: A — Lithium chloride (transpulmonary lithium dilution)

LiDCO (Lithium Dilution Cardiac Output) uses a small IV bolus of lithium chloride. A lithium-sensitive electrode on an arterial line measures the concentration-time curve. CO is calculated using the Stewart-Hamilton equation. It is then calibrated and continuous CO is derived from pulse power analysis of the arterial waveform.

Reference: Al-Shaikh Stacey 2019 Essentials of Anaesthetic Equipment