Hematology (4)

exam 2

What are the main components of blood

Plasma, erythrocytes, leukocytes, and platelet

What are the three main functions of blood

transportation, regulation, and protection

what is plasma composed of

90% water, proteins (albumin, globulins, fibrinogen), nutrients, electrolytes and waste

what is the function of erythrocytes

transport oxygen using hemoglobin; carry some CO2 as carbaninogemoglobin

what hormone stimulates RBC production

erythropoietin (EPO); released by the kidney in response to low oxygen

what is hematopoiesis

The process of blood cell formation, occuring in the red bone marrow

what are the two main categories of leukocytes

Granulocytes (neutrophils, eosinophils, basophils) and agranulocytes (lymphocytes and monocytes)

function of neutrophils

phagocytose bacteria; first responder

function of eosinophils

combat parasites and play a role in allerigic response

function of basophils

release histamine and heparin during inflammaiton and allergic reaction

function of lymphocytes

B cells produce antibodies; T cells destroy infected or abnormal cells; NK cells attack cancer cells

function of monocytes

differentiate into macrophages that engulf pathogens and debris

what are the three phases of hemostasis

vascular spasm, platelet plug formation, coagulation (clotting)

what triggers vascular spasm

vessel injury causes smooth muscle contraction to reduce blood flow

what is platelet plug formation

platelets adhere to collagen, become sticky and release chemicals to recruit more platelet

what is coagulation

a cascade of clotting factors that convert fibrinogen into fibrin, forming a stable clot

what enzyme converts fibrinogen to fibrin

thrombin

what is the final product of the coagulation cascade

fibrin mesh, which stabilizes the platelet

what are anticoagulants used for

prevent formation or extension of clots

give 3 examples of anticoagulants

heparin, warfarin (coumadin), and apixaban (eliquis)

mechanisms of heparin

activates antithrombin 3, which inhibits thrombin and factor Xa

mechanisms of warfarin

inhibit vitamin k-dependent clotting factors in the liver

what are antiplatelet drugs used for

prevent pletelet aggregation; used in heart disease and stroke prevention

examples of antiplatelet drugs

aspirin, clopidogrel

what is the antidote for heparin overdose

protamine sulfate

what is protamine sulfate

used for reversal of heparin; it works by binding to heparin; given IV and slowly

what is the antidote for warfarin overdose

vitamin K

what are thrombolytics used for

dissolve existing clots in stroke, MI, or a pulmonary embolism

what is given for iron-deficiency anemia

Ferrous sulfate or ferrous gluconate; increase dietary iron and vitamin C

what is given for megaloblastic anemia

Cyanocobalamin (vitamin B12) injections or folic acid supplements

What medication stimulates RBC production in chronic kidney disease

Epoetin alfa (Epogen)

what causes anemia

low RBC count or hemoglobin, decreased oxygen carrying capacity

what is sickle cell anemia

Genetic disorder where abnormal hemoglobin causes RBCs to become sickle shaped and block vessel

what is leukemia

cancer of WBCs causing abnormal proliferation and impaired immune function

what is thrombocytopenia

low platelet count, increased bleeding risk

what is hemophilia

genetic disorder with missing clotting factors, prolonged bleeding

what is polycythemia vera

overproduction of RBCs —> increased viscosity and risk of thrombosis

treatment for leukemia

chemotherapy, radiation, bone marrow transplant

treatment for hemophilia

replacement of missing clotting factors

treatment for thrombocytopenia

platelet transfusion and treating the underlying cause

what is given to patients with anemia due to blood loss

RBC transfusion