This document summarizes the functions of blood cells and common blood disorders. It describes how white blood cells help fight infection through chemotaxis and hemostasis helps stop bleeding. Red blood cell disorders discussed include anemias from reduced production or increased destruction. Sickle cell disease and thalassemia cause hemolysis. Polycythemia and leukopenias are also summarized. Common blood disorders like leukemia, hemophilia and disseminated intravascular coagulation (DIC) are briefly described.

1. Circulatory System
by S Jacob

2. Class 2
FUNCTIONS OF BLOOD CELLS

3. FUNCTIONS OF WBC

5. CHEMOTAXIS
• MICROBES RELEASE CHEMICALS
• THEY ATTRACT THE CELLS TO THEIR SITE
• NEUTROPHILS RESPOND MOST QUICKLY
• RELEASE ENZYMES TO DESTROY PATHOGENS
• MONOCYTES,EOSINOPHILS,LYMPHOCYTES ALL
FOLLOW

7. HEMOSTASIS
• SEQUENCE OF RESPONSE TO STOP BLEEDING
WHEN BLOOD VESSELS ARE DAMAGED
• VASOSPASM –CONTRACTION OF SMOOTH
MUSCLES OF BLOOD VESSEL WALL
– BY SUBSTANCES RELEASED FROM DAMAGED
PLATELETS
– NERVE STIMULATION
• PLATELET PLUG FORMATION

8. HEMOSTASIS
• PLATELET PLUG FORMATION
– Platelets contain ADP;ATP;Calcium ;Serotonin
Thromboxane A2; Fibrin stabilizing factor
– Platelets stick together to damaged wall with
increased stickiness, release substances which
cause aggregation & plug formation
• BLOOD CLOTTING
– CLOT IS NETWORK OF PROTEIN CALLED FIBRIN
– Cells are caught in them
• FIBRINOLYSIS—plasminogen is responsible for
this

10. BLOOD CLOTTING
• COMPLEX CASCADE OF ENZYMATIC
REACTIONS TO PRODUCE AN INSOLUBLE
PROTEIN
• 3 STAGES
• FORMATION OF PROTHROMBINASE
– EXTRINSIC & INTRINSIC PATHWAYS
• THROMBIN FROM PROTHROMBIN
• FIBRINOGEN TO FIBRIN

15. BLOOD GROUP
• Glycoproteins on plasma membrane have
antigen
• A antigen—40%
• B antigen -11%
• AB antigens -4%
• O no antigens -45%
• Rh antigen -85%

18. BLOOD DISORDERS
• ANAEMIA
• POLYCYTHEMIA
• HAEMORRHAGIC DIEASES
• LEUKOCYTE DISEASES
• MALIGNANCIES

19. ANAEMIA
• INSUFFICIENT OXYGEN CARRYING CAPACITY
• C/F TACHYCARDIA
– PALPITATIONS
– BREATHLESSNESS ON EXERTION
– GENERAL WEAKNESS
– RECURRENT INFECTIONS
• CAUSE
– IMPAIRED RBC PRODUCTION
– INCREASED DESTRUCTION

20. REDUCED PRODUCTION OF RBC
• DEFICIENCY
– IRON-MICROCYTIC HYPOCHROMIC
• IRON REQUIRMENT 2-3mg /DAY MCH <27 picograms
• IRON ABSORPTION MAY BE AFFECTED WITH OTHER
FOOD IN STOMACH
– FOLIC ACID –MALABSORPTION,COELIAC DISEASE
– VITAMIN B 12 –PERNICIOUS ANEMIA WHEN IF IS
DESTROYED BY AUTOANTIBODIES
• GASTRECTOMY,CHRONIC GASTRITIS,MALABSORPTION

21. HYPOPLASTIC ANEMIA
• BONE MARROW FAILURE
– ASSOCIATED WITH LEUKOPENIA &
THROMBOCYTOPENIA—PANCYTOPENIA
• CAUSES
– IDIOPATHIC-UNKNOWN
– DRUGS
ANTIBIOTICS,ANTICONVULSANTS,CYTOTOXIC
– IONISING RADIATION
– CHEMICALS-BENDENE & DERIVATIVES
– VIRAL INFECTION
– SECONDARY DEPOSIYS IN BONE MARROW

22. INCREASED DESTRUCTION OF RBC
• HEMOLYTIC ANEMIAS
• CONGENITAL
• GENETICALLY TRANSMITTED
• ABNORMAL HEMOGLOBIN & FRIABILITY OF
RED CELL MEMBRANE

23. SICKLE CELL DISEASE
• HEMOGLOBIS S BECOMES SICKLE SHAPED
WHEN DEOXYGENATED
• SICKLING MAY BE PERMANENT IF Hb S IS
MORE
• LIFE SPAN IS REDUCED
• THEY DO NOT MOVE SMOOTHLY THROUGH
SMALL BLOOD VESSELS
• INCREASES VISCOSITY OF BLOOD & CAUSES
THROMBOSIS,ISCHEMIA & INFARCTION

25. COMPLICATIONS
• SICKLE CELL CRISIS
• PREDISPOSED BY
PREGNANCY,INFECTION,DEHYDRATION
• INTRAVASCULAR CLOTTING & ISCHEMIA
• SEVERE PAIN IN LONG BONES CHEST &
ABDOMEN
• GALL STONE FORMATION & CHOLECYSTITIS

26. THALASSAEMIA
• REDUCED GLOBIN SYNTHESIS
• INCREASED FRIABILITY OF MEMBRANE
• HEMOLYSIS
• SEVERE CASES DIE YOUNG

27. ACQUIRED HEMOLYTIC ANEMIA
• CHEMICALS
– DRUG INDUCED –SULPHONAMIDES
– CHEMICALS-LEAD,ARSENIC
– TOXINS BY MICROBES(INFECTIONS)
• AUTOIMMUNE
• TRANSFUSION REACTION
• PARASITIC-MALARIA
• BURNS;RADIATION,HEART VALVE,DIALYSIS

28. POLYCYTHEMIA
• LARGE NUMBER OF ERYTHROCYTES IN BLOOD
• HIGH VISCOSITY & SLOWS THE SPEED OF
BLOOD FLOW-CLOTTING,INFARCTION
• PHYSIOLOGICAL-HIGH ALTITUDE,SMOKING
• PATHOLOGICAL-MALIGNANCY

29. LEUKOPENIA
• TLC < 4000/mm3
• GRANULOCYTOPENIA—AGRANULOCYTOSIS
• PREDISPOSES TO INFECTIONS
• CAUSES
– IRRADIATION
– DRUGS-CYTOTOXIC,PHENOTHIAZINES,
SULPHONAMIDES,ANTIBIOTICS
– LEUKEMIA
– SEVERE INFECTION-SEPSIS

30. LEUKEMIA
• MALIGNANT PROLIFERATION OF WHITE
BLOOD CELLS
• ACUTE
– SUDDEN ONSET & AFFECT BLAST CELLS
– AML-ADULTS 25-60
– ALL-CHILDREN 70% CURABLE
• CHRONIC
• BETTER PROGNOSIS ,AFFECTS ALL AGES

31. HAEMORRHAGIC DISEASE
• THROMBOCYTOPENIA-<1.5L
• BLEEDING DOES NOT OCCUR TILL<30,000
• REDUCED PRODUCTION
– PART OF PANCYTOPENIA
– LEUKEMIA,RADIATION,DRUGS
• INCREASED DESTRUCTION-DIC
• AUTOIMMUNE TP
• MAY BE CONGENITAL,VIRAL INFECTION

32. VITAMIN K DEFICIENCY
• REQUIRED FOR CLOTTING FACTOR
PRODUCTION
• NEW BORN-HEMORRHAGIC DISEASE OF THE
NEWBORN
• ADULTS-LIVER DISEASEVITAMIN K IS FAT
SOLUBLE & BILE SALTS ARE REQUIRED FOR
ABSORPTION

33. DIC
• THE COAGULATION SYSTEM IS ACTIVATED
WITHIN THE BLOOD VESSELS (CONSUMPTIVE
COAGULOPATHY)
• CAUSES
– SHOCK ,SEPSIS
– TRAUMA
– ACUTE PANCREATITIS
– ABRUPTIO PLACENTAE
– MALIGNANCY

34. HEMOPHILIAS
• INHERITED CLOTTING DISORDER CARRIED ON
X CHROMOSOME
• FACTOR 8 & CHRISTMAS FACTOR
• REPEATED EPISODES OF SEVERE PROLONGED
BLEEDING
• WON WILLEBRANDS DISEASE