Blood Physiology Lecture Notes PDF

 Head lines Iron metabolism Vitamin B12 cyanocobalamin Anemia and its types Polycythemia  Iron metabolism **Daily intake: 10-20mg only …10% absorbed. **Daily loss: 1mg in males,2 mg in females. **Daily needs: 1mg in males, 2mg in females. **Total quantity: 4 grams divided as...

 Head lines Iron metabolism Vitamin B12 cyanocobalamin Anemia and its types Polycythemia  Iron metabolism **Daily intake: 10-20mg only …10% absorbed. **Daily loss: 1mg in males,2 mg in females. **Daily needs: 1mg in males, 2mg in females. **Total quantity: 4 grams divided as follows: 65% in HB, 30% stored as ferritin 4% myoglobin, 1% oxidative enzymes, 0.1% transferrin  absorption, transport, utilization, and storage Absorption Fe+++ is reduced to Fe++ by vit C and HCL in food. Fe++ combine with Apo transferrin in bile to form transferrin then release its Fe++ to the blood. absorption, transport, utilization, and storage Transport Fe++ in the blood combined with apotransferrin in the blood to form transferrin ….transport iron to its utilization and storage sites. Utilization: by bone marrow Transferrin enter into erythroblasts and release its Fe++ to the mitochondria where hem is synthesized. Storage: In liver mainly Excess iron is transported by transferrin for storage in the liver where it combine with Apo ferritin to form ferritin which release its Fe++ back to the plasma where the body is needed.  Regulation of total body iron Total iron is regulated by alteration of intestinal absorption rate because there is no iron excretion: 1.No more Apo transferrin in the plasma to combine with Fe++ 2.Decrease formation of apotransferrin in the liver leads to decrease its level in the bile and plasma So…. **Metabolic pathway of iron is a closed loop in which little iron is lost consequently little iron is needed. Heamosiderosis is a disease when excess amount of iron is stored in an extremely insoluble form called hemosiderin …..which lead to damage to the storing cells Vitamin B12 (Cyanocobalamin) Normal daily requirement:- 1-2 ug /day Liver stores about 3000 ug (3mg) of vit B12 which equal to the body needs for 5 years Manifestation of vit B12 appear after about 5 years of deficient intake.  Vitamin B12 (Cyanocobalamin) Absorption : vitB12 in food + glycoprotein secreted by the parietal cells in gastric mucosa ( intrinsic factor) (VitB12-IF complex)……bind to receptors in terminal ileum….enter the intestinal cells …..released to the blood Transport : Transcobalamin to liver and bon marrow Utilization : by bone marrow Storage : in liver anemia  Anemia Definition : decreased the RBCs count and or the HB content below the normal range for age and sex. Types and causes: according to the size and HB content of RBCs 1. Normocytic normochromic anemia 2. Microcytic hypochromic anemia 3. Macrocytic anemia  Types of anemia According NORMOCYTIC MICROCYTIC MACROCYTIC To HYPOCHROMIC HYPOCHROMIC ANEMIA RBC size normal Less than More than (MCV) normal normal Amount of normal Less than HB (MCH) normal 1. Normocytic normochromic anemia Causes: it is due to 1. Hemolysis (hemolytic anemia) 2. Acute blood loss(hemorrhagic anemia) 3. Bone marrow depression (aplastic anemia) 1. Normocytic normochromic anemia First type***hemolytic anemia: hemolysis of RBCs =excessive destruction of RBCs 1. Hereditary hemolytic anemia cell membrane defect: hered. spherocytosis HB defect: sickele cell anemia, thalassemia Enzymatic defect:G.6.P.D.D,,(favism)  1. Normocytic normochromic 2. Acquired hemolytic anemia anemia Due to: *chemical poisoning *Snake venoms *Bacterial toxins *Drugs: sulphonamides *Abs against RBCs hemolytic disease of new born finish hemolytic anemia  1. Normocytic normochromic anemia ***second type ***hemorrhagic anemia due to sever blood loss ***third type *** aplastic anemia As in bone marrow suppression by X-ray viral infection chemical toxin malignant cells  2. Microcytic hypochromic anemia Iron deficiency anemia : Causes 1. Decrease intake malnutrition starvation 2. Decrease absorption vitC HCL, Tea, bile apotr 3.Decrease storage liver disease 4.Increase requirements preg, lactation, gwth 5. Chronic blood loss GIT, Heamaturia, MC Akylostoma infestation  3. Macrocytic anemia Called Megaloblastic anemia Due to defeciency of vit B12 or folic acid Causes of B12 defeciency: Decrease intake: rare Decrease storage: liver disease Dec absorption: intrinsic factors, subacute combined degeneration of spinal cord, disease of lower ilume Increase requirement rare  3. Macrocytic anemia Causes of folic acid deficiency Decrease intake: malnutrition, starvation Decrease absorption: malabsorption Decrease storage: liver disease Increase requirments: pregnancy  *****Important note ***** ****nutritional anemia **** anemia caused by nutritional disorder such as: 1. Iron deficiency anemia 2. Vit B12 deficiency and folic acid deficiency 3. Protein deficiency hypoproteinemia  Effects of anemia Physiological effects: 1. On CVS: A. Blood viscosity: PR and DBP B. Venous return: cardiac output C. Pulse pressure D. Heart rate and lastly may lead to heart failure :  Effects of anemia 2. Decreased O2 supply to the tissues 3. Hemolytic anemia lead to increase formation of bilirubin,,,,, jaundice 4. In pernicious anemia deficiency of vit B12 lead to defect in myelin sheeth metabolism lead to sub acute combined degeneration of spinal cord  Diagnosis of anemia 3 aims to diagnose anemia 1. To know if there is anemia 2. To know the type of anemia 3. To diagnose the reason of anemia  Diagnosis of anemia To know if there is anemia RBCs count HB content Hematocrit value (packed cell volum) All are low in anemia  Diagnosis of anemia To know the type of anemia Calculate blood indices (MCV, MCH, MCHC) 1.MCV: the average volume of single RBC Normal rang 90 +/- 7 cubic micron (83-97) u3 2.MCH: the average amount of HB in a single RBC Normal range 30 +/- 3 picogram (27-33) pg  Diagnosis of anemia 3.MCHC IT IS THE AMOUNT OF HB in 100ml packed RBCs N.R 33 +/- 3 % ….(30-36) % All blood indicis are 1. normal in N-N Anemia 2. in Mic-HYP Anemia 3. IN Mac-HYPR Anemia  Diagnosis of anemia To diagnose the cause of anemia check the following 1. Blood film to see the shape of RBCs 2. Estimation of serum bilirubin: hemolytic anemia 3. Measuring plasma iron: to exclude or diag IDA 4. Estimation of plasma level of vit B12, and folic acid  Polycythemia Definition : Abnormal increase in RBCs count Types and causes 1. Primary polycythemia (polycythemia vera): tumor like condition of blood forming cells 2. Secondary polycythemia may be Phyogicasioll: as in high altitude Pathological: as in heart failure chronic lung disease  Polycythemia Effect of polycythemia on CVS Increase in blood viscosity lead to increase in 1. Peripheral Resistance,,,,, 2. WORK OF HEART,,,,, 3. HEART FAILUR,,,,,,,, Increase viscosity also decrease in Blood flow to the tissues…..stagnant hypoxia Thanks for listening