9. introduction to haematology

Question 1

how much blood does a heart pump in one circulation?

Answer 1

5L

Question 2

% of RBC, white cells and plasma

Answer 2

42-45, 1, 55-58

Question 3

what does plasma contain?

Answer 3

water, electrolytes, glucose, lipids, metabolites, gas, hormones, drugs, plasma proteins: albumin, globulin and fibrinogen

Question 4

what does albumin do?

what does globulin do?

fibrinogen

Answer 4

transport, colloidal osmotic pressure

transport, clotting precursors to hormones , defence

Question 5

what is serum

Answer 5

coagulated plasma (no clotting factors)

Question 6

lifespan of RBC

Answer 6

3 months, 120 days

Question 7

which white cells are phagoctyes?

which are immunocytes?

Answer 7

• granulocytes: neutrophils, eosinophils, basophils
• monocytes

lymphocytes

Question 8

blood cell production (haemopoiesis)

Answer 8

fetus+ neonate: liver and spleen

neonate, child and adult: bone marrow

Question 9

Answer 9

Question 10

why is leukaemia common?

Answer 10

one stem cell mutation gives rise to millions of mutated daughter cells

Question 11

what does EPO do

Answer 11

kidneys detect low O2 levels and release EPO to bone marrow to signal more RBC production

Question 12

How is the production of WBC controlled?

Answer 12

Colony stimulating factors

stimulated by infections

•Recombinant CSFs useful to improve reduced WBC counts after anticancer drugs – caution leukaemia (they have mutated WBC)

interleukins also play a role

Question 13

what is haematocrit

Answer 13

packed cell volume

% of blood that is RBC

Question 14

haemoglobin

Answer 14

to identify anaemia

Question 15

Mean corpuscular volume

Answer 15

volume of individual RBC

haematocrit/ RBC per litre

Question 16

Hb/RBC

Answer 16

•gives mean corpuscular Hb (MCH) – reduced when cells are small/iron deficiency

Question 17

Hb/PCV

Answer 17

•gives mean corpuscular Hb concentration (MCHC) – lowered when cells are large with impaired haem production (macrocytic anaemia)

Question 18

what is -philia (and cytosis)

-penia

pancytopenia

Answer 18

increased count

reduced count

reduced count in everything

Question 19

how are blood groups determined

discuss groups A, B, AB, O,

Answer 19

by antigens on RBC

• A : A antigens, has b-antibodies
• B : B antigens, has a-antibodies if exposed to a blood
• AB : AB antigens cannot produce antibodies attack themselves
• O : no A or B antigens but has a and b antibodies

Question 20

clinically important blood groups

Answer 20

ABO and rhesus

Question 21

which blood groups are most common

what is O rhesus negative used for

Answer 21

A and O

universal donor for all emergencies

complication: acute haemolytic transfusion reactions

Question 22

Rhesus D antigens

Answer 22

if mother is rhesus negative, its likely to child is positive thus during birth or miscarriage, the mother will develop antibodies

the next pregnancy can be attacked by the antibodies against positive- haemolytic disease of newborn

this can be stopped by giving anti-D immunisation to mother after delivery of 1st child to bind to infant cells passed onto mother to prevent production of anti bodies