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
Thrombocyte Lab Value Abnormalities
<100,000 at risk for hemorrhage
thrombocytopenia: not enough platelets to prevent hemorrhage
- Sx: petechiae, ecchymosis, bleeding of gingivae
- Sx of stroke: VS, change in mental status, loss of speech/sensory/motor functions
Increase: in platelet count
- pt at risk for thrombosis (clot)
- sx: VS and LOC change, circulation change in extremities, c/o pain
PT/INR
lab value that evaluates bleeding/clotting status
PT (Prothrombin Time): evaluates a deficiency in clotting factors which causes prolonged PT (bleeding)
- monitor oral anticoagulant therapy (coumadin/warfarin)
- normal PT is 11-12.5 seconds
INR (international normalization ratio): standardized calculation of the PT used to monitor the effect of an oral anticoagulant
- normal range: 0.8-1.1
- therapeutic range (meaning pt is on anticoagulate): 2.0-3.0
- meaning if pt on warfarin/coumadin, PT should be 2-3 times the normal range or 20-42 seconds so they do not clot
aPTT
activated partial thromboplastin time
- normal: 30-40 seconds
- tests the intrinsic clotting system of clotting factors
- more useful to screen general plasma deficiency
- it differs from PT which does not test the intrinsic clotting system
- in hospital setting, it is used to monitor heparin therapy (heparin increases aPTT).
- therapeutic level is 2.5-3 times the control (75-120 second )
Erythrocyte Sedimentation Rate (ESR or Sed Rate)
indication of inflammation but can also indicate anemia, infection, pregnancy, or even aging.
Getting a good health hx is important when you get this lab value.
> 20 mm/hr indicates inflammation
*indicates cell destruction - acute and chronic inflammatory disease, malignancies, MI
Decrease indicates microcytic RBC or abnormally shaped rbc (sickle cell anemia)
CRP
C-Reactive Protein
titer > 1.2 indicates inflammation
appears 6-10 hours after acute inflammation and peaks in 48-72 hours.
