Heme Tests Flashcards
Hematopoiesis
production of blood cells
occurs in bone marrow (RBC, WBC, Thrombocytes (platelets), come from stem cells)
> 10 billion/day and need to keep this level of production
Function of Blood
- Transportation of O2, nutrients, hormones, waste products
- Regulation: fluid, acid-base balance, electrolytes
- Protection: clotting and fighting infections
Leukocytes (Granulocytes)
neutrophils: segmented neutrophil (segs) which are
- Bands: young or immature neutrophils that are pushed out into periphery (blood system) to help out
Eosinophil: allergy and parasitic infections
Basophil: allergy and inflammation
Phagocytosis: phagocytes ingest small cells, cell fragments, microorganisms.
Leukocytes (Agranulocytes)
lymphocytes: cellular and humoral immunity (B & T lymphocytes)
Monocytes: potent phagocytes, live in blood
Macrophages: monocytes that have left blood and moved to tissue
Resident macrophages: live and start out in tissues, they never enter blood system
Natural Killer Cells
WBC Ranges
Normal range: 5,000-10,000
greater than 10,000 = indicates infection
less than 5,000 = leukopenia (you have decreased response to infection)
RBC’s
erythrocyte:
- hemoglobin carries O2
- lifespan = 120 days
- reticulocyte = immature RBC (sometimes can get pushed into peripheral circulation but we don’t want this to happen b/c if they are immature they aren’t functioning to full capacity)
Erythropoiesis
RBC production
- stimulated by hypoxia
- controlled by erythropoietin (hormone secreted by kidneys to increase production of RBC)
- production is dependent on availability of nutrients (need enough iron, folic acid, and B12)
- would need to stimulate RBC production b/c of hemolysis
Thrombocytes
Platelets
- regulated by thrombopoietin (hormone produced by liver and kidneys)
- main reason we have thrombocytes = hemostasis (arrest of bleeding)
Two types of responses to bleeding:
- Vascular response: vasoconstriction (slows blood from getting out) and endothelial wall stickiness, lasts 20-30min following vessel injury
- Platelet response: activated by exposure to collagen. Platelets stick together (adhesiveness) and form clumps (aggregation or agglutination)
- done through clotting cascade
Clotting Cascade:
Plasma clotting factors - stimulated by activated plasma proteins by intrinsic (inside blood vessel) and extrinsic (outside blood vessel) pathways.
-ultimately thrombin converts fibrinogen to fibrin which is essential for clot
Prothrombin converted to thrombin (thrombin to fibrinogen)
Clots regulated by anticoagulation and fibrinolysis
- heparin = natural anticoagulant
- antithrombin and antithromboplastin help maintain blood flow through blood vessel (prevents clotting)
Heme Problems: Subjective Questions to Ask
- c/o
- past health hx: anemia, blood disease, bleeding disorders, recurrent infections
- medications: Rx meds, OTC, supplements, vitamins, herbs (common cardiac meds: warfarin, plavix, aspirin, PPI’s H2 blockers, eliquis, heparin, xarelto)
- Surgical/procedural Hx: splenectomy, heart valve replacement, duodenectomy, blood transfusion
Heme Problem: Objective Assessment
Complete physical exam
Lab tests: CBC with diff, ESR, CRP
CBC Values
Erythrocytes:
- Males: 4.7-6.1 x 100,000/uL
- Females: 4.2-5.4 x 100,000/uL
Hgb:
- Males: 14-17 g/dL
- Females: 12-16 g/dL
Hct (% of RBC compared to total blood volume):
- Males: 42-52%
- Females: 37-47%
WBC: 5,000-10,000 /uL
Thrombocytes: 150,000-400,000/uL
Differential includes: segs, bands, monocytes, eosinophils, basophils
RBC Lab Value Abnormalities
Increased = polycythemia, dehydration Decreased = anemia, hemorrhage
-Sx: fatigue, pallor, tachycardia, tachypnea, DOE, decreased BP
WBC Lab Value Abnormalities
> 10,000 = infection, inflammation, malignancy
<5,000 (leukopenia) = virus, bone marrow suppression
- Sx = signs of infection
- Neutrophils: shift to left - increase bands released to help fight infection.
- Neutropenia - <1,000 bone marrow does not produce enough
