The packed cell volume (PCV) is the percentage of the blood volume which is occupied by [[Erythrocyte|red blood cells]]. The PCV is usually estimated by subjecting a small blood sample to centrifugation to compress the blood cells into a minimal volume before the PCV is measured against a standard scale.
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The packed cell volume (PCV) is the percentage of the blood volume which is occupied by [[Erythrocyte|red blood cells]]. The PCV is usually estimated by subjecting a small blood sample to centrifugation to compress the blood cells into a minimal volume before the PCV is measured against a standard scale. PCV differs from haematocrit values very slightly as haematocrit is measured automatically using techniques which exclude the microscopic spaces between the red blood cells - when comparing serial samples use the same technique (manual PCV or automated haematocrit) each time to make sure the samples can be compared.