hematology mohamad h qari, md, frcpa. hematology cellular components components of blood red blood...
Post on 30-Dec-2015
Embed Size (px)
HematologyMohamad H Qari, MD, FRCPA
HematologyCellular ComponentsComponents of BloodRed Blood CellsWhite Blood CellsInflammatory processCoagulationBlood TypingClotting disorders
HematopoeisisThree developmental periodsMesoblasticBlood islands of yolk sacPrimarily RBC productionEmbryonic hemoglobin producedHepaticAt 6 weeks cell production in liverFetal hemoglobin producedSpleen, thymus, lymph nodes also active prod.MyeloidAt 5th month Bone Marrow becomes site of prod.Liver & spleen now ExtramedullaryHemoglobin A (22)
Requirements For HematopoiesisStem CellsGrowth FactorsMicroenviroment
Stem Cell theoryPluripotent stem cell originator of all cellsGives rise to cells committed to specific developmentResearch supporting the theoryPHSC has self-maintaining abilityCommitted cells differentiate continuously/ No Reverse Flow
Stem cells in ResearchPluripotent cells derived from:Cell mass of embryos at blastocyst stage (IVF)Fetal tissue from terminated pregnancyApplicationIdentification of factors of cellular decision-makingDevelopment and testing of drugsGeneration of cells and tissue for therapy
Cytokines & Growth FactorsCytokines stimulate or inhibitPrevent apoptosisColony-Stimulating Factors produced by many different cellsInterleukins numbered according to discovery
Components of BloodPlasmaTransport mechanism90-92% water. 6-7% proteins2-3% FatsCarbohydrates (glucose)ElectrolytesGases (O2, CO2)Chemical messengers
Components of BloodRed Blood CellsErythrocyteHemoglobin O2 bearing moleculeComprised of 4 subunits:Globin (binds to 1 O2 molecule)Heme (iron)100% saturation = 4 globin subunits carrying O2Each gram of hemoglobin = 1.34 ml O2Cellsalive.com
Blood Products and Blood TypingBlood TypesAntigensA, B, AB, ORh factorRh+ = ~85%Rh- = ~15%
Components of BloodRed Blood Cells (cont.)Oxygen TransportOxy-hemoglobin dissociation curve2,3-DPG
Components of BloodWhite Blood Cells (Leukocytes)MarginationPhagocytosis
The macrophage is using its internal cytoskeleton to envelop cells of the fungus Candida albicans.
Components of BloodLeukocytes (cont.)White Blood Cell CountLeukopoiesisGranulocytesNeutrophilBasophilEosinophilMonocytesLymphocytesHuman Neutrophil: Phagocytosis of Strep pyogenes
Components of BloodLeukocytes (cont.)ImmunitySubpopulation of lymphocytes known as T cells and B cellsT cells develop cellular immunity.B cells produce humoral immunity
Components of BloodInflammatory ProcessMAST CELLS.Immunoglobulin E antibody IgE, Antigens Antigens stick to the mast cell IgE antibodies, causing granules in the mast cell to fire their contents into the surrounding tissue.This releases a host of inflammatory materials - leukotrienes, tumor necrosis factor, interleukin-4 and other cytokines that turn on other inflammatory cells.These materials cause fluid to leak from the capillaries and white cells including neutrophils, T cells and eosinophils to leave the circulation. The end result is a "local inflammatory response", a red, itchy welt.
Components of BloodHemostasis- 3 mechanismsVascular spasmContraction of tunica mediaPlatelet plugPlatelet aggregationCoagulationFormation of fibrin clot
Components of BloodHemostasis (cont.)FibrinolysisLysis of clot (plasmin)ThrombosisThrombolyticsMedications affecting clot formationAlter the enzyme on the platelet.Affect the coagulation cascade.Enhance clotting.
Coagulation Cascade - Synopsis
This scanning electron micrograph shows the fine structure of a blood clot. Platelets released from the circulation and exposed to the air use fibrinogen from the blood plasma to spin a mesh of fibrin.
General Assessment - ManagementFocused History and Physical ExamSAMPLE historyHematological disorders are rarely the chief complaint.Physical examEvaluate nervous system function.Skin signs
General Assessment - ManagementPhysical Exam (cont.)Lymphatic signsGastrointestinal signsEpistaxisAtraumatic bleeding gumsThrushAtraumatic splenic/hepatic painMusculoskeletal signsArthralgia (rheumatoid arthritis)HemarthrosisCardiorespiratory signsTachycardia, cx pn, dyspnea - CHFGenitourinary signsHematuriaMenorrhagiaInfection
Blood Products and Blood Typing
Blood Products and Blood Typing= no reaction+ = reaction
Blood Products and Blood TypingBrady; Paramedic Care Principles and Practice
Diseases of ErythrocytesAnemiasAnemia is a sign, not a separate disease process.Signs and symptoms may not be present until the body is stressed.Differentiate chronic anemia from acute episode.Treat signs and symptoms.Maximize oxygenation and limit blood loss.Establish IV therapy if indicated.
Diseases of ErythrocytesBrady; Paramedic Care Principles and Practice
Diseases of ErythrocytesSickle Cell DiseaseNormal red cells maintain their shape as they pass through the capillaries and release oxygen to the peripheral tissues (upper panel). Hemoglobin polymers form in the sickle rell cells with oxygen release, causing them to deform. The deformed cells block the flow of cells and interrupt the delivery of oxygen to the tissues (lower panel).
Diseases of ErythrocytesSickle Cell Disease (cont.)Sickle cell crisesVaso-occlusiveMusculoskeletal/abdominal painPriapismRenal/cerebral infarctionsHematologicalLowered hemoglobinSplenic sequestrationInfectiousManagementFollow general treatment guidelines prn.Consider analgesics.
Diseases of ErythrocytesPolycythemiaOverproduction of erythrocytes.Occurs in patients > 50 years old or with secondary dehydration.Most deaths due to thrombosisResults in bleeding abnormalities:Epistaxis, spontaneous bruising, GI bleeding.Management:Follow general treatment guidelines.
Diseases of LeukocytesLeukopenia/NeutropeniaToo few white blood cells or neutrophils.Follow general treatment guidelines and provide supportive care.LeukocytosisAn increase in the number of circulating white blood cells, often due to infection.Leukemoid reaction
Diseases of LeukocytesLeukemiaCancer of hematopoietic cellsInitial presentationAcutely ill, fatigued, febrile and weak, anemic.ThrombocytopeniaOften have a secondary infection.ManagementFollow general treatment guidelines.Utilize isolation techniques to limit risk of infection.
Diseases of LeukocytesLymphomasCancers of the lymphatic systemHodgkin'sNon-HodgkinsPresentationSwelling of the lymph nodesFever, night sweats, anorexia, weight loss, fatigue, and pruritisManagementFollow general treatment guidelines.Utilize isolation techniques to limit risk of infection.
Clotting DisordersThrombocytosis and ThrombocytopeniaThrombocytosisAn abnormal increase in the number of plateletsThrombocytopeniaAn abnormal decrease in the number of plateletsSequestrationDestruction (ITP)Decreased productionManagementProvide supportive care and follow general treatment guidelines.
Clotting DisordersHemophiliaDeficiency or absence of a blood clotting factorDeficiency of factor VIII causes hemophilia A.Deficiency of factor IX causes hemophilia B.Deficiency is a sex-linked, inherited disorder.Defective gene is carried on the X chromosome.Signs & SymptomsNumerous bruises, deep muscle bleeding, and joint bleeding.
Clotting DisordersHemophilia (cont.)ManagementTreat the patient similarly to others.Administer supplemental oxygen.Establish IV access.Be alert for recurrent or prolonged bleeding, and prevent additional trauma.Von Willebrands DiseaseDeficient component of factor VIIIGenerally results in excessive bleeding.Generally is not serious; provide supportive care.
Clotting DisordersDisseminated Intravascular Coagulation
Components of BloodLeukocytes (cont.)Autoimmune diseaseMay be specific or generalAlterations in the immune processImmunosuppressionHIVAnti-rejection medicationChemotherapy/Cancer
System activation of coagulation cascade.Results from sepsis, hypotension, OB complications, severe tissue or brain injury, cancer, and major hemolytic reactions.Multiple MyelomaCancerous disorder of plasma cells.Pathologic fractures are common.
Anticoagulants/AntiplateletsClassifying agentsAnticoagulantsBlock synthesis and activation of clotting factorsAntiplateletsInterfere with platelet aggregation or activationFibrinolyticsDissolve fibrin component of thrombi
Anticoagulants/AntiplateletsAnticoagulantsWarfarinBlocks activation of Vit KInterferes w/ coagulation factors II, VII, IX, and XUnfractionated HeparinBinds antithrombin III (AT-III)Inhibits coagulation factors IX and X and thrombinHirudin (medicinal leech)Prevents thrombin binding
Anticoagulants/AntiplateletsAntiplateletsAspirinPrevents platelet activation through cyclooxygenase blockade.Prevents production of thromboxane A2Allows prostacyclin synthesisTiclodipineDeforms platelet membrane fibrinogen receptor
Anticoagulants/AntiplateletsAntiplatelets (cont.)Glycoprotein IIb-IIIa Receptor InhibitorsG IIb-IIIa = platelet membrane receptor of fibrinogenAbciximabEptifibatideTirofibanFibrinolyticsActivate plasminogen to plasmin = fibrinolysisStreptokinaseAnistreplaseTissue Plasminogen ActivatorReteplaseUrokinase
Transfusion ReactionsHemolytic ReactionSigns & SymptomsFacial flushing, hyperventilation, tachycardia, hives, chest pain, wheezing, fever, chills, and cyanosisTreatmentStop transfusion, change all IV tubing, and initiate IV therapy with normal saline or la