Blood, haemostasis and blood grouping Flashcards
what are the functions of blood?
- Transport – blood gases e.g., Oxygen and carbon dioxide in occasion with respiration – nutrients for digestive system, hormones from endocrine cells to target tissues, heat and waste products
- Regulation – pH via buffers – temperature vasoconstriction and vasodilation – water content of tissues due to osmotic pressure gradients due to proteins and dissolved ions
- Protection – clotting (haemostasis) – white blood cells phagocytosis to fight disease
state the composition of blood
- Blood is a connective tissue – formed in red bone marrow
- Blood plasma
- Platelets – haemostasis
- Erythrocytes – red blood cells
- Monocytes
- Neutrophils - clotting
- Lymphocytes – white blood cell – phagocytosis
Whats the pH of blood?
Alkaline – 7.35 to 7.45 counting for 5L and 8% body weight
Whats albumin?
In blood plasma protein – carrier protein to shuttle various molecules through circulation
Also, body water balance by creating osmotic pressure
What are erythrocytes?
Red blood cells – biconcave discs
No nuclei
Containing haemoglobin – protein giving red pigment and carries oxygen (up to 4)
What are leukocytes?
White blood cells
Immune response fighting pathogens
5 types grouped as to whether containing granules
1. Granulocytes (neutrophils, eosinophils and basophils)
2. Agranulocytes (small lymphocytes and monocytes)
What are neutrophils?
phagocytise bacteria
What are eosinophils?
Involved in allergies and killing parasites
What are basophils?
Mast cells of connective tissue releasing histamine, heparin and more
Involved in inflammatory response
What are small lymphocytes?
Forming plasma cells which produce antibodies (immune response)
What are monocytes?
Phagocytises debris
What are platelets including real name?
Fragments of cells in clotting response
Form platelets plug in wound stemming bleeding and sealing break
Process of haemostasis
what are the two stages for formation of formed elements?
Formed elements created in red bone marrow
- Haemopoiesis – production of formed elements
- Erythropoiesis – production of eryocytes
What is erythropoietin (EPO)?
- Key hormone helping regulate RBC production
- As stimulates formation of erythrocytes
- Basal level of EPO circulates in blood stream at all times
- When hypoxia detected in kidney EPO production increases stimulating red bone marrow to increase RBC production
What is haematocrit?
- Percentage of RBCs in blood sample
- Average 45% lower in female
If a patient is dehydrated what happens to their haematocrit?
- Increases – higher % RBC in sample
- Water content of plasma decreased
What determines a patients blood grouping?
- Determined by antigens in plasma membrane (glycolipids and proteins)
What can happen if you give the incoorect blood group during transfusion?
- Agglutinates created (clumps blood together)
- Blocking blood vessels
- Attacking donor RBC and rupturing and noy carrying oxygen
- ABO blood groups (A, B, AB and O)
- Ph blood group (antigen D blood group) - either Ph positive or negative on presence or absence of rhesus molecule on red blood cell
- These groupings merge e.g. A+ and AB -
What are agglutinins?
- Body made antibodies depending on antigen of red blood cell (ABO group) – react against antigens not recognised
- Process called agglutination
What are Rh antibodies?
- Not spontaneously formed in Rh-
- If given to Body of Rh+ they produce anti-D antibodies this takes time when transfused so not registered until subsequent encounters will be rejected
What does the Rh factor mean in pregnancy?
- If motor with Rh- carries child of Rh+ then mother becomes sensitive to babies’ antigens and creates anti-D antibodies for subsequent pregnancies after first
- So treated with anti-D immunoglobulin that neutralises mothers Rh factor preventing sensitisation
- Otherwise, haemolytic disease of new born condition – mothers destroy babies red blood cells causing baby to be anaemic and hypoxic even brain damage or death if no transfusion is performed
What’s blood typing?
- Serum with anti-A and anti-B agglutinins added to sample with saline
- Agglutination occurs between agglutin (antibody) and antigen a or B – blood type is found
What is the universal donal?
- Type 0 are universal donors – no antigens to agglutinate
What is the universal recipient?
- Type AB are universal recipients – no antibodies that agglutinate with donor antigens
if patient is A group what antibodies do they get?
anti-B antibodies
