Hematology and hemostasis

Leukocytes

major function is inflammatory and immune responses

play important part of body defense system

recognize, respond, and remove foreign material/damaged or dead cells

majority of cells not circulating but in pools that transport through blood vessels

pools

cells not yet released in circulation

proliferation pool

cells being formed in bone marrow which are available upon maturation

storage pool

mature cells mainly stored in the spleen and bone marrow

circulating pool

freely moving cells from which sample was drawn

marginal pool

cells that are stuck to or rolling around walls of small vessels and not freely circulating

tissue pool

left the vessels to enter body cavities and tissues(site of functioning of most wbc)

penia

decreased number of cells in the blood

philia/cytosis

increased number of cells in the blood

left shift

increased numbers of immature neutrophils in the blood

leukemia

neoplastic cells in the blood or bone marrow

leukemoid response

marked leukocytosis, result of inflammatory disease, can be mistaken for leukemia

granulocytes

granules present in cytoplasm

neutrophils, eosinophils, basophils

agranulocytes

no granules present in cytoplasm

lymphocytes and monocytes

neutrophils

most abundent

segmented nucleus

band cell- young neutrophil

cytoplasm stains pink

phagocytosis and inflammation

eosinophils

bilobed/trilobed nucleus

feline- numerous, small and rod shaped granules

canine- vary in size and large granules

cytoplasm stains red/red orange

inflammation/allergic conditions, attract histamine, parasitic infection

basophil

elongated, segmented, coiled nucleus

cytoplasm stains gray to blue and dark blue to purple granules

initiate an acute inflammatory response and rare in peripheral blood

lymphocytes

second most abundent

round/ indented nucleus

blue staining of cytoplasm

major cell involved in immune response, lymphocytosis(young animals), lymphoid neoplasia

monocyte

largest leukocyte

kidney bean nucleus

abundent cytoplasm and stains bluish grey

phagoctosed particles

phagocytosis. macrophages, and immune response

platelets

pieces of cytoplasm of megakaryocytes

fragments may clump especially in cats

Function of Platelets- clotting

aggregate to form blood clot

initiate clotting

assist in clot retraction

increase bleeding if count is below 50,000 microliters

requires von will brand factor to stabilize the platelet plug

CBC includes

PCV, TP, WBC count, RBC morphology, WBC differential, platelet estimate

From hematocrit tube

PCV and TP

From Leuko TIC/hemacytometer

WBC count

From blood smear

WBC differential, platelet estimate, RBC morphology

PCV and TP

Always fill 2 hematocrit and will use serum and plasma

Blood Smear

Feathered edge, monolayer, thick edge

Types of Romansky type stains

wrights stain, diff-quik, and dip quik

Pros of stains

practical, inexpensive, readily available, easy to maintain/prepare/use

New methylene blue stain

excellent nuclear detail and doesn’t stain cytoplasm

WBC differential- blood smear

begin at feathered edge

move to monolayer

count number of different types of WBC in 100 cells

Platelet estimate- blood smear

determine number of platelets per high powered field

Leukotic plus- counting WBC

lyses RBC, preserves WBC(fixes nucleus)

Hemacytometer- counting WBC

counting chamber

WBC count

under 100x magnification, count WBC in 9 primary squares of counting chamber and calculate average from both grids

Platelet count

counted in primary square #5

Platelet estimate

evaluate platelet numbers in counting area of blood film

WBC differential

from blood stain identify, categorize, count all WBC in each category, until 100 WBCS are counted

Also observe RBC and platelet estimate

QUATS

PCV, TP, BUN, BG- don’t replace CBCs and chem profiles

Anticoagulants

prevent clotting, for WBC samples, and plasma samples

Citrates

forms insoluble complex with calcium

citrated plasma(clotting profile)

blue top

Heparin

prevents conversion of prothrombin to thrombin during clotting

sodium, potassium. lithium or ammonium salt

plasma sample, not for WBC differential

green top

Ethylenediamine Tetraacetic Acid (EDTA)

preferred for CBC

forms insoluble complex with calcium

Not for plasma samples

Purple top