haematocrit
Học thuậtThân thiện
Definition
- Noun:
- A measuring instrument: A device, typically a centrifuge and a calibrated tube, used to determine the relative volume of red blood cells in a sample of blood.
- A measurement or ratio: The percentage of the total blood volume that is occupied by red blood cells, as determined by the instrument.
Usage Examples
- Noun (Instrument):
- The technician used a haematocrit to spin down the blood sample.
- The haematocrit tube is filled with blood and then centrifuged.
- Noun (Measurement):
- The patient's haematocrit was low, indicating possible anemia.
- A normal haematocrit for an adult male is typically between 40% and 54%.
Advanced Usage
- Clinical Context: The term is used almost exclusively in medical, laboratory, and clinical settings. It is a standard part of a complete blood count (CBC).
- The doctor ordered a CBC to check the patient's hemoglobin and haematocrit levels.
Variants and Related Words
- Hematocrit: The American English spelling variant of haematocrit. Both spellings are correct and refer to the same instrument and measurement.
- Packed Cell Volume (PCV): A synonymous term for the haematocrit measurement (the ratio).
- Centrifuge: The machine that spins the haematocrit tube to separate the blood components.
Synonyms
- Packed Cell Volume (PCV): (Specifically for the measurement/ratio)
- Erythrocyte Volume Fraction: (A more technical term for the measurement)
Related Phrases / Compound Terms
- Haematocrit tube: The thin, glass or plastic capillary tube used in the test.
- Haematocrit centrifuge: The specific centrifuge designed to hold and spin haematocrit tubes.
- Haematocrit reading: The numerical result (percentage) obtained from the test.
Noun
- a measuring instrument to determine (usually by centrifugation) the relative amounts of corpuscles and plasma in the blood
- the ratio of the volume occupied by packed red blood cells to the volume of the whole blood as measured by a hematocrit