3.2. Hemostasis Test - Notes taken from the lecture of Sir Antonio Pascua, Jr., RMT PDF

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HEMATOLOGY 2 LABORATORY TESTS FOR HEMOSTASIS TESTS FOR HEMOSTASIS SCREENING TESTS TO CHECK THE INTEGRITY OF THE BLOOD VESSELS: 1. BLEEDING TIME 2. CAPILLARY FRAGILITY RESISTANCE TEST a. RAMPEL LEEDES also called as or or we used BP cup to apply pressure to the BV or a Torniquet if BP cup is not avai...

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HEMATOLOGY 2

LABORATORY TESTS FOR HEMOSTASIS TESTS FOR 1° HEMOSTASIS SCREENING TESTS TO CHECK THE INTEGRITY OF THE BLOOD VESSELS: 1. BLEEDING TIME 2. CAPILLARY FRAGILITY / RESISTANCE TEST a. RAMPEL LEEDES - also called as “Torniquet test” or “Hess Test” or “Positive Pressure” - we used BP cup to apply pressure to the BV or a Torniquet if BP cup is not available * Principle: Capillary pressure is increased by partially obstructing the venous blood. This will give rise to extravasation of blood which will be manifested in the form of small hemorrhage called “Petechiae” * Procedure: > Get the BP then compute for the Midpoint Example: 120/80 (Total=200, Midpoint=100) > Midpoint will be administered in the BP for 5mins * Result: Petechiae (+)  0-10 Petichiae = Normal  11-20 Petichiae = Equivocal (middlepoint)  >20 Petichiae = has Problems with BV a1. QUICK’S METHOD a2. GOTHLIN’S METHOD b. SUCTION CUP - also called as “Petechiometer Method” or “Negative Pressure” - we use Suction cup instead of BP cup - the pressure is constant @ 200 mmHg for 1min - has the same procedure with Rampel Leedes ASSESSMENT TESTS OF PLATELETS: I. QUANTITATIVE TESTS: 1. DIRECT METHOD / TOCANTINS - same way of counting PLTs using Hemacytometer - has the same procedure as RBC & WBC counting - Fluid: Reese & Ecker or Tocantins (Isotonic) - Composition: Citrate, Formaldehyde, Buffer, & Brilliant Cresyl Blue

JOYCE ANN S. MAGSAKAY

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- Formula:

2. INDIRECT METHOD / FONIO’S - an estimate count of Platelet using Blood smear - you count 10 OIO fields - Stain: Wright’s stain - Formula:

 10-40 RBC = 1 Platelet  100 RBC = 3-10 Platelets  200 RBC = 5-20 Platelets REFERENCE RANGE 0-49,000/uL 50,000-99,000/uL 100,000-149,000/uL 150,000-199,000/uL 200,000-400,000/uL 400,000-599,000/uL 600,000-800,000/uL > 800,000/uL

INTERPRETATION Markedly ↓ Moderately ↓ Slightly ↓ Low Normal Normal Slightly ↑ Moderately ↑ Markedly ↑

3. UNOPETTE SYSTEM - contains 1% Ammonium oxalate - Dilution = 1:100 - you count 25 RBC squares - Formula:

4. AUTOMATED COUTING MACHINE - most convenient way of counting Platelets - blood cells are determined based on its MCV - Volume is directly proportional to the Size > Platelets = 2-20 fL > RBC = >20 fL

* THROMBOCYTOPENIA (↓ Platelets) BS MEDICAL LABORATORY SCIENCE | OLFU VALENZUELA

HEMATOLOGY 2

LABORATORY TESTS FOR HEMOSTASIS Marrow infiltrative process

Leukemia, Lymphoma, Multiple Myeloma, Myelofibrosis Aplasia Aplastic Anemia, Fanconi’s Anemia, Chemotherapy, Radiation Infective blood Vit. B12 deficiency, Folic production Acid deficiency, Alcohol ingestion, MDS, PNH Congenital disorders Bernard-Solier, TAR Syndrome, May-Hegglin Hyperspenism, KasabachAbnormal Platelet Merit distribution Increased Platelet Primary Immune, Secondary destruction Immune, Microangiopathic a. PRIMARY THROMBOCYTOPENIA - ITP, Post-Transfusion, Heparin-Induced b. SECONDARY THROMBOCYTOPENIA - SLE, Viral infection, Lymphoproliferative diseases * THROMBOCYTOSIS (↑ Platelets) - Polycythemia Vera, Essential Thrombocytopenia - Reactive: after Hemorrhage, IDA, Malignancy, Epinephrine administration II. QUALITATIVE TESTS: 1. PLATELET ADHESION TEST a. BLEEDING TIME - checks both Platelets & BV - Standard skin wound: 2-4 mm - for in-vivo platelet function & number - Methods: 1. Duke’s Method: in fingers 2. Ivy’s Method: in forearms @ 40mmHg 3. Coply-lalitch: in fingers 4. Adelson Crosby: dip finger in NSS @ 37°c until bleeding stops 5. McFarlane: same principle w/ Adelson Crosby but it only uses Earlobe as the site of puncture 6. Aspirin Tolerance Test: assess the effect of a standard dose of Aspirin - Results:  Normal: 4 Aspirin  VWF: 2 Aspirin, ↑ Bleeding time

FACTORS AFFECTING BLEEDING TIME:  Elasticity of the cut tissue  Ability of blood vessels to constrict & retract JOYCE ANN S. MAGSAKAY

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 Mechanical & Chemical action of platelets in the formation of Hemostatic plug Abnormal Bleeding Time:  Thrombocytopenia  Hypofibrinogenemia  VWF Disorder  Connective Tissue Disorders: Warfarin’s Syndrome, Pseudocytoma, Scurvy b. PLATELET/GLASSBEAD RETENTION TEST - for in-vitro platelet adhesiveness - Platelets will meet a tube with glass beads - Check the cell count to determine whether the Platelets have adhered on the glass beads or not - Result: Plasminogen > Plasminogen Activators > Plasmin > Fibrinogen - Add Thrombin so it will form a clot - Instead of 48 hrs, Normal lysis will only take you for more than 2hrs because all the things you need for lysis are concentrated on the Euglobulin

- if there’s FDP, there’s too much lysis up to the point that Phagocytes can no longer remove these FDPs 1. PROTAMINE SULFATE DILUTION TEST 2. ETHANOL GELATION TEST - if the Blood sample contains FDP & it is mixed with Protamine Sulfate & Ethanol, it will form para-coagulation (clot/agglutination) - it will help us determine if lysis is due to Primary or Secondary fibrinolysis  Primary Fibrinolysis: lysis even w/o fibrin  Secondary Fibrinolysis: lysis because there’s fibrin 3. LATEX FDP TEST - Reagent: has latex particles coated w/ Ab against Fragments D & E - Plasma with D, E, & Fibrinogen will form agglutination - if the remaining plasma after removing the fibrinogen still have a clot, it confirms that you have FDP (fragment D & E) 4. LATEX D-DIMER TEST - determine whether the FDP is from fibrinogen or from fibrin - Reagent: has latex particles coated w/ Ab against D-dimer - it will be positive for Fibrin in a mater of 4 hrs 5. STAPPHYLOCOCCAL CLUMPING TEST - further help us check if we have FDP such as X & Y - Add bacteria S. auerus Strain New Man B2C to the patient’s plasma - If it’s positive, having a clot, it means you have an FDP (fragment X & Y) 6. TANNED RED CELL HEMAGGLUTINATION INHIBITION - Reagent: has Ab against FDP & Fibrinogen - There’s a red cell coated with fibrinogen - If the patient’s plasma has FDP, there will be no Hemagglutination since the reagent is already used up in the patient’s plasma with FDP - If there’s no Hemagglutination occurred, it means you have FDP

TESTS FOR FIBRIN DEGRADATION PRODUCT (FDP): - not normally present in the blood JOYCE ANN S. MAGSAKAY

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BS MEDICAL LABORATORY SCIENCE

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OLFU VALENZUELA...