Haematocrit (HCT) or Packed Cell Volume (PCV)

PCV or HCT  is the volume of packed red cells obtained after centrifugation of a sample of anticoagulated venous or capillary blood. It is expressed either as a percentage of volume of whole blood or as a decimal fraction.

 Factors that can affect the Haematocrit:

  • Living at a high altitude
  • Pregnancy
  • Significant recent hemorrhage
  • Recent blood transfusion
  • Severe dehydration

 Causes associated with high haematocrit:

  • Dehydration
  • Polycythemia Vera (a myeloproliferative disorder associated with the production of excessive numbers of red cells)
  • Lung or heart disease
  • Administering of Testosterone supplement therapy
  • Dengue fever (high haematocrit is a danger sign of an increased risk of dengue shock syndrome)
  • Chronic obstructive pulmonary disease (COPD)
  • Other pulmonary conditions associated with hypoxia
  • Doping or erythropoietin (EPO)
  • Use of Anabolic androgenic steroid (AAS)
  • Capillary leak syndrome

 Causes associated with low haematocrit:

  • Associated with long-term illness, infection or a white blood cell disorder such as leukemia or lymphoma
  • Vitamin or mineral deficiencies
  • Lung or heart disease Recent or long-term hemorrhage.

Erhabor O, et al. Interpretation of Full Blood Count Parameters in Health and Disease. Haematol Int

J 2021, 5(1): 00180.