Hematology 2 Prelims: Hemostasis and Coagulation

HEMATOLOGY 2 2ND SEMESTER l S.Y. 2022-2023 PRELIMS CHAPTER 1: COAGULATION AND HEMOSTATIS - Contains autonomic nerve ending and the vasa vasorum (small...

HEMATOLOGY 2 2ND SEMESTER l S.Y. 2022-2023 PRELIMS CHAPTER 1: COAGULATION AND HEMOSTATIS - Contains autonomic nerve ending and the vasa vasorum (small network of CIRCULATORY HEMOSTASIS blood vessel) - Balance between bleeding and clotting. - Bleeding (hemorrhage) Arterioles are the microscopic continuation of - Clotting (thrombosis) arteries that gives branches to the so called metarterioles which in turn joins the 4 Major Components of Hemostasis capillaries 1. Vascular System Venules microscopically sized vein, connects 2. Platelet (Thrombocytes) capillaries to the vein 3. Blood Coagulation Factors Capillaries the capillaries + arterioles + venules are 4. Fibrinolysis and ultimate tissue repair the major vessel of microcirculation Sinusoids specialized type of capillaries found in the Minor Factors Bm, spleen and liver 1. Complement Vasculature Physiology 2. Kinin System Vasoconstriction 3. Serine Protease Short lived reflex reaction of the smooth muscle Processes involved in hemostasis after injury to a small in the vessel wall produced by the sympathetic vessel: branches of the autonomic nervous system 1. Blood vessel spasm Stenosis/ narrowing of the blood vessel – 2. Formation of Platelet plug normal response of the body to the pain 3. Contact among damaged blood vessel, platelets and coagulation proteins 4. Development of blood clot around the injury The Role of Endothelium 5. Fibrinolytic removal of excess hemostatic Contains connective tissue such as collagen and material to re-establish vascular integrity elastin Highly active metabolically and involved in Blood Vascular System: clotting process by producing or storing clotting Artery > Arteriole > Capillaries > Venule > Vein > components Plasminogen Activator – rapid lysis of fibrin 3 Coats/Tunics of The Blood Vessels clots 1. Tunica Intima (inner tubular cavity) Weibel – Palade Body - Made up of endothelium (simple squamous epithelial) Organelle of the endothelial cells discovered by - Endothelial cells thickened by Weibel and Palade in 1964 subendothelial connective tissue layer The storage granule for Von-Willebrand factor 2. Tunica media (middle) “VWF” (bridge to connect platelet and - Thickest coat collagen), a molecule for platelet adhesion - Smooth muscle + elastic fiber Also, a storage for P selectin (a receptor for 3. Tunica adventitia leukocytes) TOLEDO, JN. 1  HEMATOLOGY 2 2ND SEMESTER l S.Y. 2022-2023 PRELIMS ENDOTHELIAL PLATELETS Functions Dysfunction Megakaryopoiesis Angiogenesis Tumor necrosis Megakaryoblast > Promegakaryocyte > Coagulation factor megakaryocyte > Platelet Inflammation Interleukin 1 Early precursor – BFU -M and CFU Immune Viral infection response Bacterial toxin Mature Platelet Cholesterol Oxidative Younger platelets are larger than the old ones modified Inactive/unstimulated platelets circulates as a lipoproteins thin smooth-surfaced disk MEGAKARYOPOIESIS If the endothelium is disrupted, following processes will occur: 1. Initially, rapid vasoconstriction for up to 30 History in Hemostasis mins. Reduces blood flow and promotes contact 2nd century A.D hemophilia was first recognized activation of platelets and coagulation factors. 2. 2nd phase – platelets adhere immediately to the 12th century A.D Moises Maimonides reported 2 exposed sub endothelial connective tissue deaths due to bleeding after particularly collagen. The aggregated platelets circumcision enhance sustained vasoconstriction by releasing 1803 clinical description of families with thromboxane A2 and vasoactive amins hemophilia (love of hemorrhage) (serotonin and amine) was first published by Johann 3. 3rd phase – coagulation is initiated through both Lukas Schonlein the intrinsic and extrinsic system 1842 platelets were described 4. Finally, fibrinolysis occurs to re-establish 1905 theory on blood coagulation – by vascular integrity Paul Morawitz was accepted 1913 lee and White blood clotting time Maintenance Of Vascular Integrity was performed 1930 introduction of prothrombin time 3 essential factors by quick 1. Circulating Platelets 1940 platelet count and bleeding time 2. Adrenocorticoids were introduced 3. Ascorbic acid 1964 cascade and waterfall theory was introduced – about fibrin mesh The integrity of arterioles and venules depends on the following: HEMOSTASIS ▪ Vasoconstriction balance between bleeding and clotting Involve the ▪ Formation of platelet plug to the site of injury interaction between the following: ▪ Formation of fibrin clots 1. Blood vessel 2. Platelets ❖ Arteries are thicker and more resistant to 3. Coagulation disruption but more dangerous in cases of 4. Fibrinolysis injury 5. Body repair TOLEDO, JN. 2  HEMATOLOGY 2 2ND SEMESTER l S.Y. 2022-2023 PRELIMS The Process: SOURCES: - Liver (most copies/primary) MAINTAIN THE NORMAL HEMOSTAIS - Kidney (major for EPO) - Smooth skeletal muscle Stop the bleeding Maintain the Dissolve the - Stromal cell by producing clot. clot integrity clot and let the tissue repair Regulates the production of platelets by the BM Stimulate and differentiate megakaryocyte Blast cells resemble lymphocyte under light microscope Lymphocyte resembles the following: blast cells, agranulocyte, rubricyte FAST FACTS Mature/condensed and coarse chromatin 5 days = start to increase platelet 8-9 days = turnover for megakaryopoiesis Megakaryocyte Progenitors 12 days = days it takes to maximally optimize platelet production MK-1/ Megakaryoblast 1/3 (33%) of them are located on the spleen 20-50 UM in diameter (14-18 UM) meanwhile 2/3 (66%) of them are in the Blue cytoplasm circulation (some books say 30%- spleen and N:C ratio 10:1 70% - circulation MK-II / promegakaryocte Platelet Normal Value 20-60 UM in diameter (15-40 UM) SI = 150-450 x 10^9/L (others 200-400x Indented nucleus 10^11/L) Last stage capable of endomitosis Conventional = 150,000 – 450,000 UL Slightly higher in women than in men MK-III/ megakaryocyte Slightly lower in both sexes when over 65 yrs. 40-120 UM in diameter 830-50/160 UM) Old Multiple nuclei No nucleoli is visible Spleen Lobulated nucleus Lymphoid organ Counts for