Transcript Hematology intro

Hematology
Mohamad H Qari, MD, FRCPA
Hematology
Cellular Components
Components of Blood
Red Blood Cells
 White Blood Cells
 Inflammatory process
 Coagulation

Blood Typing
Clotting disorders
Hematology
Spleen
Blood
Kidneys
Hematopoietic
System
Bone
Marrow
Liver
Hematopoeisis
Three developmental periods
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Mesoblastic
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Hepatic
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Blood islands of yolk sac
Primarily RBC production
Embryonic hemoglobin produced
At 6 weeks cell production in liver
Fetal hemoglobin produced
Spleen, thymus, lymph nodes also active prod.
Myeloid
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At 5th month Bone Marrow becomes site of prod.
Liver & spleen now Extramedullary
Hemoglobin A (22)
Requirements For
Hematopoiesis
Stem Cells
Growth Factors
Microenviroment
Stem Cell theory
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Pluripotent stem cell originator of all cells
Gives rise to cells committed to specific
development
Research supporting the theory
PHSC has self-maintaining ability
Committed cells differentiate continuously/ No
Reverse Flow
Stem cells in Research
Pluripotent cells derived from:
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Cell mass of embryos at blastocyst stage (IVF)
Fetal tissue from terminated pregnancy
Application
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Identification of factors of cellular decision-making
Development and testing of drugs
Generation of cells and tissue for therapy
Cytokines & Growth Factors
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Cytokines stimulate or inhibit
 Prevent apoptosis
 Colony-Stimulating Factors produced by
many different cells
 Interleukins numbered according to discovery
Components of Blood
Plasma Components
Plasma
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Water
90%
Transport mechanism
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90-92% water.
6-7% proteins
2-3%
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Fats
Carbohydrates
(glucose)
Electrolytes
Gases (O2, CO2)
Chemical messengers
Other
3%
Protein
7%
Cellular Components
Pluripotent Stem Cell
Myeloid Multipotent
Stem Cells
Common Lymphoid
Stem Cells
Unipotent
Progenitors
Lymphocytes
WBC’s
Basophils
Eosinophils
Neutrophils
Monocytes
RBC’s
Thrombocytes
Platelets
Erythrocytes
Erythropoietin
Components of Blood
Red Blood Cells
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Erythrocyte
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Hemoglobin – O2
bearing molecule
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Comprised of 4
subunits:
• Globin (binds to
1 O2 molecule)
• Heme (iron)
100% saturation = 4
globin subunits
carrying O2
• Each gram of
hemoglobin =
1.34 ml O2
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Blood Products and Blood Typing
Blood Types
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Antigens
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A, B, AB, O
Rh factor
Rh+ = ~85%
 Rh- = ~15%
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Blood transfusion
Components of Blood
Red Blood Cells
(cont.)
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Oxygen Transport
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Oxy-hemoglobin
dissociation curve
2,3-DPG
Components of Blood
White Blood Cells (Leukocytes)
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Margination
Phagocytosis
The macrophage is using its internal
cytoskeleton to envelop cells of the fungus
Candida albicans.
Components of Blood
Leukocytes (cont.)
White Blood Cell Count
 Leukopoiesis
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Granulocytes
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Neutrophil
Basophil
Eosinophil
Monocytes
 Lymphocytes
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Human Neutrophil:
Phagocytosis of Strep pyogenes
Components of Blood
Leukocytes (cont.)
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Immunity
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Subpopulation of lymphocytes known as T cells and B cells
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T cells develop cellular immunity.
B cells produce humoral immunity
Components of Blood
Inflammatory Process
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MAST CELLS.
 Immunoglobulin E antibody
IgE,
Antigens
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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.
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Components of Blood
Hemostasis3 mechanisms
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Vascular spasm
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Platelet plug
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Contraction of
tunica media
Platelet
aggregation
Coagulation
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Formation of fibrin
clot
Components of Blood
Hemostasis (cont.)
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Fibrinolysis
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Lysis of clot (plasmin)
Thrombosis
Thrombolytics
 Medications affecting clot formation
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Alter 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 Management
Focused History and
Physical Exam
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SAMPLE history
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Hematological
disorders are rarely
the chief complaint.
Physical exam
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Evaluate nervous
system function.
Skin signs
General Assessment - Management
Physical Exam (cont.)
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Lymphatic signs
Gastrointestinal signs
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Musculoskeletal signs
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Arthralgia (rheumatoid arthritis)
Hemarthrosis
Cardiorespiratory signs
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Epistaxis
Atraumatic bleeding gums
Thrush
Atraumatic splenic/hepatic pain
Tachycardia, cx pn, dyspnea - CHF
Genitourinary signs
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Hematuria
Menorrhagia
Infection
Blood Products and Blood Typing
Blood Typing - ABO
Blood type
Antigen present
Antibody
on erythrocyte
present in
serum
O
AB
B
A
None
A and B
B
A
Anti-A, Anti-B
None
Anti-A
Anti-B
Blood Products and Blood Typing
Compatibility Among ABO Blood Groups
Reaction with serum of Recipient
Donor Cells
AB
B
A
O
AB
B
A
O
-
+
+
-
+
+
-
+
+
+
-
-= no reaction
+ = reaction
Blood Products and Blood Typing
Brady; Paramedic Care Principles and Practice
Diseases of Erythrocytes
Anemias
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Anemia is a sign, not a separate disease process.
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Signs and symptoms may not be present until the body is
stressed.
Differentiate chronic anemia from acute episode.
Treat signs and symptoms.
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Maximize oxygenation and limit blood loss.
Establish IV therapy if indicated.
Diseases of Erythrocytes
Brady; Paramedic Care Principles and Practice
Diseases of Erythrocytes
Sickle Cell Disease
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Normal 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 Erythrocytes
Sickle Cell Disease (cont.)
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Sickle cell crises
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Vaso-occlusive
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Hematological
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Musculoskeletal/abdominal pain
Priapism
Renal/cerebral infarctions
Lowered hemoglobin
Splenic sequestration
Infectious
Management
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Follow general treatment guidelines prn.
Consider analgesics.
Diseases of Erythrocytes
Polycythemia
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Overproduction of erythrocytes.
Occurs in patients > 50 years old or with
secondary dehydration.
 Most deaths due to thrombosis
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Results in bleeding abnormalities:
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Epistaxis, spontaneous bruising, GI bleeding.
Management:
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Follow general treatment guidelines.
Diseases of Leukocytes
Leukopenia/Neutropenia
Too few white blood cells or neutrophils.
 Follow general treatment guidelines and
provide supportive care.
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Leukocytosis
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An increase in the number of circulating
white blood cells, often due to infection.
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Leukemoid reaction
Diseases of Leukocytes
Leukemia
Cancer of hematopoietic cells
 Initial presentation
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Acutely ill, fatigued, febrile and weak, anemic.
 Thrombocytopenia
 Often have a secondary infection.
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Management
Follow general treatment guidelines.
 Utilize isolation techniques to limit risk of infection.
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Diseases of Leukocytes
Lymphomas
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Cancers of the lymphatic system
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Presentation
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Hodgkin's
Non-Hodgkins
Swelling of the lymph nodes
Fever, night sweats, anorexia, weight loss, fatigue, and
pruritis
Management
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Follow general treatment guidelines.
Utilize isolation techniques to limit risk of infection.
Clotting Disorders
Thrombocytosis and Thrombocytopenia
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Thrombocytosis
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An abnormal increase in the number of platelets
Thrombocytopenia
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An abnormal decrease in the number of platelets
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Sequestration
Destruction (ITP)
Decreased production
Management
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Provide supportive care and follow general treatment
guidelines.
Clotting Disorders
Hemophilia
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Deficiency or absence of a blood clotting factor
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Deficiency of factor VIII causes hemophilia A.
Deficiency of factor IX causes hemophilia B.
Deficiency is a sex-linked, inherited disorder.
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Defective gene is carried on the X chromosome.
Signs & Symptoms
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Numerous bruises, deep muscle bleeding, and joint
bleeding.
Clotting Disorders
Hemophilia (cont.)
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Management
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Treat the patient similarly to others.
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Administer supplemental oxygen.
Establish IV access.
Be alert for recurrent or prolonged bleeding, and prevent
additional trauma.
Von Willebrand’s Disease
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Deficient component of factor VIII
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Generally results in excessive bleeding.
Generally is not serious; provide supportive care.
Clotting Disorders
Disseminated Intravascular Coagulation
Components of Blood
Leukocytes (cont.)
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Autoimmune disease
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May be specific or general
Alterations in the immune process
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Immunosuppression
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HIV
Anti-rejection medication
Chemotherapy/Cancer
System activation of coagulation cascade.
Anticoagulants/Antiplatelets
Classifying agents
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Anticoagulants
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Antiplatelets
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Block synthesis and activation of clotting
factors
Interfere with platelet aggregation or activation
Fibrinolytics
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Dissolve fibrin component of thrombi
Anticoagulants/Antiplatelets
Anticoagulants
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Warfarin
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Unfractionated Heparin
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Blocks activation of Vit K
Interferes w/ coagulation factors II, VII, IX, and X
Binds antithrombin III (AT-III)
Inhibits coagulation factors IX and X and thrombin
Hirudin (medicinal leech)
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Prevents thrombin binding
Anticoagulants/Antiplatelets
Antiplatelets
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Aspirin
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Prevents platelet activation through
cyclooxygenase blockade.
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Prevents production of thromboxane A2
Allows prostacyclin synthesis
Ticlodipine
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Deforms platelet membrane fibrinogen receptor
Anticoagulants/Antiplatelets
Antiplatelets (cont.)
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Glycoprotein IIb-IIIa Receptor Inhibitors
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G IIb-IIIa = platelet membrane receptor of fibrinogen
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Abciximab
Eptifibatide
Tirofiban
Fibrinolytics
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Activate plasminogen to plasmin = fibrinolysis
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Streptokinase
Anistreplase
Tissue Plasminogen Activator
Reteplase
Urokinase
Hemorrhage
Class I
Class II
Class III
Class IV
Blood Loss (ml)
Up to 750
750-1500
1500-2000
>2000
Blood Loss (%
volume)
Up to 15%
15%-30%
30%-40%
>40%
Pulse
<100
>100
>120
>140
BP
Normal
Normal
Decreased
Decreased
Pulse Pressure
Normal or
increased
Decreased
Decreased
Decreased
Resp. Rate
14-20
20-30
30-40
>35
Urine Output (ml/hr) >30
20-30
5-15
Negligible
Mental Status
Slightly
anxious
Mildly
anxious
Anxious,
confused
Confused,
lethargic
Fluid Replacement
(3:1) rule
Crystalloid
Crystalloid
Crystalloid and Crystalloid and
blood
blood
Transfusion Reactions
Hemolytic Reaction
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Signs & Symptoms
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Facial flushing, hyperventilation, tachycardia, hives,
chest pain, wheezing, fever, chills, and cyanosis
Treatment
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Stop transfusion, change all IV tubing, and initiate IV
therapy with normal saline or lactated Ringer’s.
Consider furosemide, dopamine, and diphenhydramine.
Transfusion Reactions
Febrile Non-hemolytic Reactions
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Signs & Symptoms
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Headache, fever, and chills
Treatment
Stop transfusion, change all IV tubing, and
initiate IV therapy with normal saline or lactated
Ringer’s.
 Consider Diphenhydramine and an antipyretic.
 Observe closely to ensure reaction is nonhemolytic.
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