Hematology Flashcards
Packed Cell Volume
Percentage of whole blood composed of erythrocytes - manual
Reticulate count of a regenerative anemia
> 60,000 ul
Hematocrit
Percentage of whole blood composed of erythrocytes calculated by an electronic cell counter
Differential Nucleated Cell Count
Minimum of 100 nucleated cells are counted within a counting area and classified as: segemented neutrophils, band neutrophils, lymphocytes, monocytes, eosinophils, basophils, nucleated RBC, other
Normal size of cat, horse and cow RBC
39-52 fl
Normal size of a dog RBC
60-72 fl
Light Scatter Measurement (Flow)
Cells passed through a flow cell that is intersected by a focused laser beam. Light scattered in angles correlates with cellular properties leading to ability to differentiate cell types
Refractometer
Estimates the concentration of solute in fluid, since solute bends light passing through the fluid proportionate to the solute concentration
Techniques for getting a complete blood count
Direct Measurements
Microscopic Procedures
Calculations
Hematologic techniques performed with automated instrumentation:
Cell particle counting and sizing
Spectrophotometry
Electronic Cell Counting
Cells are suspended in an electrolyte medium that conducts electricity, deflections in current are proportional to the size of the cell
Yellow pigmentation of plasma suggests what in small animals
Suggestive of icterus - increased bilirubin concentration in the blood
Yellow pigmentation of plasma in large animals is suggestive of
Normal Plasma - may be due to carotene pigments associated with diets
Reticulate count of a poorly regenerative anemia
10,000-60,000ul
White or opaque plasma may be due to
postprandial collection or may be due to disease associated with abnormalities in lipid metabolism
___________________________
Often due to not fasting before blood draw
Reticulocyte
Immature erythrocytes that still have organelles for protein synthesis and aerobic metabolism
Mean Cell Hemoglobin Concentration =
MCHC = Hgb / (PCV% x 100)
Describe reticulocyte maturation in cats
Aggregate reticulocytes become punctate reticulocytes in about 12 hours. Punctates persist for 12 days.
______________________
Punctates are not polychromatic with wrights stain and not counted in reticulocyte count.
Refractometers are used in clinical practice to estimate
Plasma Protein
Urine Specific Gravity
Total Nucleated Cell Count (Total Leukocyte Concentration)
Detects all nuclei in solutions from which red blood cells have been removed by lysis
Primarily used to calculate the concentration of specific leukocyte types - after differentiated cell count
Hematocrit =
HCT = MCV x (RBC / 10)
Species that does not release reticulocytes
Horses
There should be how many platelets per oil immersion field?
6-10
Decreases in MCHC may be due to
Iron deficiency
Red coloration of plasma is due to the presence of
Hemoglobin
Reticulate Count of a non regenerative anemia
0-10,000ul
Red Cell Distribution Width (RDW)
Describes the relative width of the size distribution curve
When stained with Wrights Stain - reticulocytes are _____________ RBCs
Polychromatic
Reticulocyte concentration can be measured by
Flow technology
Manually
Increases in MCHC are indicative of
Artifacts. Due to hemolysis, lipemia or presence of Heinz bodies
In dogs, reticulocytes mature in ________ hours
24-48 hours
Buffy coat consists of
Leukocytes
Nucleated Erythrocytes
Platelets
