lab.3:haematocrit packed cell volume
TRANSCRIPT
Zhikal O. Khudhur/Assist lecturerMuhammad Qadir/RA_____________________________________________Hematology– 3rd Stage /1st Semester
https://tiu.edu.iq/
2021 - 2022
TIU - Faculty of ScienceMedical Analysis Department
Lab.3:Haematocrit packed cell volume
Haematocrit or packed cell volume
• HCT measures the volume of packed red bloodcells (RBC) relative to whole blood. Also knownas packed cell volume (PCV)
It is a simple test to identify conditions like anemiaor polycythemia and also to monitor response tothe treatment.
PurposeTo pack the RBC using the centrifuge force. • Forcing all red cell below and plasma above, by centrifugal force.
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Material requirements
o Capillary tubeso 75 mm long capillary tubes with an internal
diameter of 1 mm.
oOily-clay sealer
o Hematocrit centrifuge
o Hematicrit reader
Manual Haematocrit Determination
• A volume of anticoagulated or capillary blood isplaced in a glass tube.
The glass is then centrifuged (5• minutes) so thatcomponents:
theblood is separated into its main
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red cells,white cells,
platelets
plasma.
Haematocrit is the ratio of the height of the red cellcolumn to that of the whole blood sample in the tube
• The two methods currently used for directmeasurement of PCV are:
• 1. Macro- method using Wintrobe tubes
• 2. Micro- method using capillary tubes
• The micro-method is more popular because:
a/ centrifugation lasts for a shorter time with thismethod
b/ it results in better packing of the red cells.
Procedure• Blood samples should be as fresh as possible and well mixed.
1. Using a capillary tube, allow blood to enter the tube by capillary
action stopping at 10-15 mm from one end. Wipe the outside of
the tube.
Seal the dry end by pushing into plasticine two or three times. If
heat sealing is used, rotate the dry end of the tube over a fine
Bunsen burner flame.
Place the tube into one of the centrifuge plate slots, with the sealed
end against the rubber gasket of the centrifuge plate. Keep a record
of the patient number against the centrifuge plate number.
Centrifuge for 5 minutes.
Read the PCV in the micro haematocrit reader. The hematocrit result
is expressed in either a percentage or liter per liter (l/l).
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3.
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5.
Tot I Blood
Volum,
Pl8Sm8
Whole II CENTRIFUGE
BloodP8cked
Red CellsWh iteBloodCeJls
Rad
Blood C'oi!!Hs
POJ=4 ·�
Read the value with Hct reader or ruler.
3
How to read a hematocrit
about 18%
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12
Note:• It is preferable to the test in duplicate.
Normal Ranges
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Children
Children
Children
6 mo. to 5 Year = 0.33 (33%)
5-11 Years = 0.34 (34%)
(36%)12-13 Years = .36
Adult males = 0.40 –
Adult females = 0.37
0.52 (40% - 52%)
– 0.47 ( 37% - 47%)
Increased levels: Decreased levels:• acute blood loss• dehydration / hypovolemia
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anemiaorgan failure &
malignanciescirrhosis of the liver protein malnutrition deficiency of vitamins pregnancy
severe diarrhea
• polycythemia vera•
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• Or the effect of some drugs.
Clinical Problems