تويت
packed cell volume ,,PCV
When whole blood is centrifuged in a hematocrit tube, the blood cells are
packed together at the bottom of the tube by the centrifugal force as these are heavier than plasma. This volume is called packed cell volume (PCV) or hematocrit (Hct). PCV represents the volume of the blood cells per unit volume of whole blood and is expressed as a percentage (Hct%). [/SIZE]
Normal Values of Hematocrit percentage or Packed cell volume:
[SIZE="3"]Male = 41.9 – 48.7%[SIZE="3[/COLOR]"][SIZE="3[/SIZE]"] Female = 35.4 – 42.0%
However, high and low PCV can be seen in the following clinical conditions.
High PCV is seen in:
1-Polycythemia
Because number of RBCis increased
2-Dehydration
Because we loose a lot of water >>so the present of plasma to the RBC is increased
3-Burn
Also here we loose water which directly effect the plasma volume
Low PCV is seen in:1
-Anemias
Here absolutely >>number of RBC is decreasd
2-Pregnancies
Because in pregnant woman all body fluid and water increase so,,plasma volume increase
Clinical Significance:
Changes in Hct% affects the maximum transport of the oxygen. A low Hct% decreases the maximum content of oxygen in a volume of blood due to less hemoglobin. Whereas high Hct% decreases the maximum cardiac output because of increase in blood viscosity
From hematocrite we can measure the intra vascular blood volume by using this equation:
Intra vascular volume = plasma volumex100
100minas pcv
Note: The Value of plasma volume should be taken as 3 liters
When whole blood is centrifuged in a hematocrit tube, the blood cells are
packed together at the bottom of the tube by the centrifugal force as these are heavier than plasma. This volume is called packed cell volume (PCV) or hematocrit (Hct). PCV represents the volume of the blood cells per unit volume of whole blood and is expressed as a percentage (Hct%). [/SIZE]
Normal Values of Hematocrit percentage or Packed cell volume:
[SIZE="3"]Male = 41.9 – 48.7%[SIZE="3[/COLOR]"][SIZE="3[/SIZE]"] Female = 35.4 – 42.0%
However, high and low PCV can be seen in the following clinical conditions.
High PCV is seen in:
1-Polycythemia
Because number of RBCis increased
2-Dehydration
Because we loose a lot of water >>so the present of plasma to the RBC is increased
3-Burn
Also here we loose water which directly effect the plasma volume
Low PCV is seen in:1
-Anemias
Here absolutely >>number of RBC is decreasd
2-Pregnancies
Because in pregnant woman all body fluid and water increase so,,plasma volume increase
Clinical Significance:
Changes in Hct% affects the maximum transport of the oxygen. A low Hct% decreases the maximum content of oxygen in a volume of blood due to less hemoglobin. Whereas high Hct% decreases the maximum cardiac output because of increase in blood viscosity
From hematocrite we can measure the intra vascular blood volume by using this equation:
Intra vascular volume = plasma volumex100
100minas pcv
Note: The Value of plasma volume should be taken as 3 liters
تعليق