The SI unit for blood pressure is kilopascal (kPa).
While blood pressure is traditionally measured in millimeters of mercury (mmHg), the use of kilopascals (kPa) is becoming increasingly common, especially in modern healthcare settings. mmHg is a legacy unit related to the mercury sphygmomanometers historically used to measure blood pressure.
Here's a breakdown:
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Traditional Unit: Millimeters of Mercury (mmHg) - based on the height a column of mercury rises in a sphygmomanometer.
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SI Unit: Kilopascal (kPa) - part of the International System of Units.
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Conversion: 1 mmHg is approximately equal to 0.133 kPa.
Why the shift to kPa?
The move toward kPa aligns with the international standardization of units within the SI system and reflects a reduced reliance on mercury-based medical devices due to environmental and safety concerns.
Example:
A blood pressure reading of 120/80 mmHg can also be expressed as approximately 16/11 kPa (rounded).
