Flashcards in Determining blood cell parameters Deck (10):
How is red cell count estimated?
- Dilute the blood 200x and place a layer 0.1mm thick on a special ruled haemocytometer slide
- To dilute the blood, 5 microlitres is added to 995 microlitres of HAYEM’S solution using a capillary pipette
- By counting those in a known area, the number or red cells in 1 litre of blood can be estimated
- E.g. counting the amount in 5 medium squares (volume=0.02mm^3) , and mutiplying by 10^10 to get per litre
How is haematocrit measured?
Haematocrit (Hct) is the percentage of the volume of a sample of blood occupied by the red cells
- This can be measured using a centrifuge
- The blood will separate into layers
- The ratio of the length of the red cell column to the total length is haematocrit
How is Hb concentration measured?
Haemoglobin concentration in the anticoagulated blood sample is measured using the HemoCue Hb 201+ system,
How is MCV calculated?
Hct / RBC count x 100
fl (10^-15 l)
How is MCH calculated?
(Hb x 10) / RBC count
pg (10-12 g)
How is MCHC calculated?
(Hb x 100) / Hct
80 – 100 fl
26 – 34 pg
32 - 36 g/dl