Blood

1. Unit III
BLOOD
SUBMITTED TO
MRS. JISHA S.
PRINCIPAL,
ST. CATHERINE’S HOSPITAL
& SCHOOL OF NURSING
SUBMITTED BY
MR. EARNEST LAMUEL
NURSING TUTOR,
ST. CATHERINE’S HOSPITAL
& SCHOOL OF NURSING

2. COMPOSITION &
FORMATION OF BLOOD

3. Introduction
Circulating body fluids include blood and lymph that flow through a closed
system of vessels. Haematology is the study of body fluids like blood and
lymph. Blood is a fluid connective tissue which is red colored, opaque and
alkaline in reaction. Arterial blood is bright red blue due to presence of
oxyhemoglobin and venous blood is dark red due to presence of reduced
haemoglobin. Body contains about 5 litres of blood in an adult which
comes to about 8% of body weight.

5. Physical Properties
• Color – Red due to presence of Hb
• pH – 7.4
• Specefic Gravity – 1.055 – 1.065

7. Composition
Blood is composed of plasma
and blood cells. Gases present
in blood are –
•Oxygen
•Carbon Dioxide
•Nitrogen

9. Blood Cells
• Erythrocytes (RBCs) – 5
million/mm³ or µL of blood
• Leukocytes (WBCs) – 4,000 –
11,000/mm³ of blood
• Thrombocytes (Platelets) –
150,000 – 400,000/mm³ of blood

11. Plasma
Plasma is a clear, slightly yellow liquid, containing a large number of
organic and inorganic substances dissolved in water. Plasma contains
approximately 91% of water and 9% solids.
Of the solids, about 7% are the plasma proteins which consist of serum
albumin, serum globulin and fibrinogen. Other organic substances present
are glucose, amino acids, fatty acids, phospholipids, cholesterol,
hormones, enzymes, antibodies etc.
Inorganic substances are sodium, potassium, calcium, magnesium, iron,
copper, zinc, chloride, bicarbonate, etc. Also gases like oxygen, carbon
dioxide, nitrogen, etc. are present in the plasma.

13. Plasma Proteins
• Albumin – 3.5-5g/100mL
• Globulin – 2-3.5g/100mL
• Fibrinogen – 0.2-0.3g/100mL

15. Functions
•Role in coagulation of
blood – Fibrinogen is
essential for the
coagulation of blood.
•Role in defence
mechanism of body
•Role in transport
mechanism
•Role in maintenance of
osmotic pressure in
blood
•Role in regulation of
acid-base balance
•Role in viscosity of blood

16. FUNCTIONS OF
BLOOD

17. Transport of Respiratory Gases
Hemoglobin in the red blood cells carries oxygen from the
lungs to the tissues for the oxidation of food and
production of energy. From the tissues, carbon dioxide is
carried to the lungs, where it is exhaled.

18. Excretory Function
Various waste products of the tissue metabolism are
carried by blood to the excretory channels – kidneys, skin
and lungs.

19. Nutritional Function
The end products of digestion are absorbed from the
digestive tract and transported by blood to various tissues
for growth and supplying energy.

20. Acid-Base Balance
Normal pH of blood is 7.4. The enzymes of our body can act
only within a narrow range of this pH. Large amounts of acids
are produced daily as a result of metabolism. Blood contains
various buffers, which can check the rise in hydrogen ion
concentration.

21. Transport of Hormones
Hormones are secretions of endocrine or ductless glands,
which are directly poured into the blood. Blood caries
them to their target organs.

22. Defence Mechanism
The white blood cells especially the neutrophils and monocytes
can attack the disease causing organisms like bacteria, virus,
fungus, etc. Blood also contains antibodies or
immunoglobulins, which can act against the foreign antigens.

23. Thermoregulation
Normal body temperature is 98.4˚F or 37˚C. Blood helps
in easy dissipation of heat from warmer to cooler parts of
body, thus helping to keep in proper functioning of
different enzymes.

24. Thermoregulation
Blood maintains and regulates the fluid
contents in various body compartments.

25. Osmotic Pressure
Blood contains plasma proteins, which exert the
osmotic pressure. This is responsible for the balance
of fluid in the vascular system.

26. BLOOD CLOTTING

27. Hemostasis
The word ‘hemostasis’ means ‘arrest of bleeding’ by
physiological process. Blood has got a natural, unique property of
fluidity, when inside the blood vessels, and a tendency to set
into a semisolid jelly, when shed. Both these properties are
essential for our life.
When there is a small injury to a blood vessel, a number of
events are initiated that ultimately arrest the bleeding by the
formation of a clot. The hemostatic events occur are as follows-

29. Hemostatic Events
I. Immediate vasoconstriction – at the site of injury or vasospasm
II. Formation of a platelet plug or temporary hemostatic plug or primary
hemostasis – This process begins within a few seconds after the injury.
The injury to the blood vessel causes the sub endothelial tissue of the
vessel to become exposed. The exposed collagen fibres of the sun
endothelial tissue can attract platelets. Circulating platelets will come
and adhere to these exposed collagen fibres. This binding is reinforced by
the ‘von Willebrand’s Factor (vWF). The whole process is called ‘platelet
adhesion’. The whole adhered platelets can attract more circulating
platelets to the injury site, resulting in ‘platelet aggregation’. After some
time, a clump of platelets is formed at the site of injury called ‘the loose
platelet plug’.

30. Hemostatic Events
III. Secondary Hemostasis – The loosely aggregated platelets in
the temporary plug are converted into a definitive clot by the
deposition of fibrin. The formation of fibrin is by a process
called clotting or coagulation. Coagulation or coagulation is
defined as the process in which blood looses its fluidity and
becomes a jelly like mass few minutes after it is shed out or
collected in a container. Coagulation mechanism includes a
cascade of reactions in which some inactive enzymes are
activated and the activated enzymes, in turn, stimulate other
inactive enzymes.

31. Hemostatic Events
Normally, blood contains two sets of substances called
procoagulants and anticoagulants. Procoagulants are substances
which prevent clotting. There is a balance between these two so
that the anticoagulant action predominates over the other. But
when an injury occurs, procoagulants are activated.

32. Procoagulant/Clotting Factors
• Factor I – Fibrinogen
• Factor II – Prothrombin
• Factor III – Tissue Thromboplastin
• Factor IV – Calcium
• Factor V – Proaccelerin/Labile
factor
• Factor VI – The existence of this
factor is not accepted
• Factor VII – Proconvertin or stable
factor
• Factor VIII – Antihemophillic factor
• Factor IX – Christmas factor
• Factor X – Stuart-Prower factor
• Factor XI – Plasma thromboplastin
antecedent (PTA)
• Factor XII – Hagerman factor or
glass factor
• Factor XIII – Fibrin stabilizing factor

34. Mechanism
The fundamental reaction of coagulation is the conversion of the
soluble plasma protein fibrinogen into insoluble fibrin threads. For
this the following reactions have to occur –
• Thrombin acts upon fibrinogen to form fibrin
• Thrombin is formed by activation of prothrombin
• Prothrombin to thrombin activation occurs in the presence of factor
Xa is produced by two major pathways
• The intrinsic pathway
• The extrinsic pathway

35. BLOOD GROUPING

36. Blood Groups
There are four main blood groups (types of blood) – A, B, AB and
O.Blood group is determined by the genes you inherit from your
parents. Each group can be either RhD positive or RhD negative,
which means in total there are eight main blood groups.
Several systems of classification of the types of blood are there, like
ABO, Duffy, Rhesus (Rh), MNS, Kell, Lewis, Lutheran, etc. of these,
the most important ABO and Rh systems, discovered by Karl
Landsteiner in 1901.

38. ABO System
According to this system, the blood grouping is done depending
on the presence or absence of two agglutinogens (antigens),
present on the surface of the red cells. The agglutionogens are
named A and B and the blood group is determined according to
the agglutination present. Agglutinins or antibodies against the
agglutinogens are present in the plasma and are given the names
‘α’ and ‘β’. ‘A agglutinogen’ will react with to ‘α agglutinin’ and
‘B agglutinogen’ with ‘β agglutinin’. Human beings are divided
into four main groups.

39. ABO System
Blood Group Agglutinogen Agglutinin Percentage of population
in India
A A Β (anti B) 25%
B B α (anti A) 25%
AB AB - 5%
O - α’ and ‘β 45%

40. RH System
This system was first discovered in Rhesus monkeys and hence
the name. In this system, there are several subgroups of Rh
antigen – C, D, E, c, d, e, etc. but there are no naturally
occurring antibodies. Out of antigens, the D antigen is the most
important.
When RhD is present in the RBC, the person is named Rh positive
and when it is absent, he is named Rh negative. About 90% of
Indian population are Rh positive and 10% are Rh negative. The
Rh antibodies, or anti-D antibodies are absent in both Rh
negative and Rh positive individuals.

41. RH System
This system was first discovered in Rhesus monkeys and hence
the name. In this system, there are several subgroups of Rh
antigen – C, D, E, c, d, e, etc. but there are no naturally
occurring antibodies. Out of antigens, the D antigen is the most
important.
When RhD is present in the RBC, the person is named Rh positive
and when it is absent, he is named Rh negative. About 90% of
Indian population are Rh positive and 10% are Rh negative. The
Rh antibodies, or anti-D antibodies are absent in both Rh
negative and Rh positive individuals.

43. RH Incompatibility
If an Rh negative receives Rh positive blood, there will not be
any immediate reaction. However, the donor’s red cells induce
the formation of anti degeneration antibodies in the recipient
later, the anti D antibodies immediately destroy the donor RBC
and this is called Rh incompatibility. Haemolytic disease of new
born is also an example of Rh Incompatibility.

44. Uses of Blood Grouping
• Blood Transfusion
• To diagnose or to predict Rh incompatibility
• To investigate a case of disputed paternity
• Medicolegal value for criminal cases
• Organ transplantation
• Susceptibility of certain diseases

45. BLOOD PRODUCTS
& THEIR USE

46. Blood Products & Their Use
A blood product is any therapeutic substance prepared from
human blood. This includes – whole blood, blood components, and plasma
derivatives. Whole blood is not commonly used in transfusion medicine.
Blood components include – red blood cell concentrates or
suspensions, platelets produced from whole blood or via
apheresis, plasma, and cryoprecipitate. Plasma derivatives are plasma
proteins prepared under pharmaceutical manufacturing conditions, these
include: albumin; coagulation factor concentrates; and immunoglobulins.

48. Blood Products & Their Use
Blood products may also be called blood-based products to differ
from blood substitutes, which generally refer to artificially produced
products. Also, although many blood products have the effect of volume
expansion, the group is usually distinguished from volume expanders,
which generally refer to artificially produced substances and are thereby
within the scope of blood substitutes.

50. Thank You!