PCV and Microscope Flashcards
Functions of Blood and the Circulatory System (7)
- Transport of O2 and CO2
- Transport nutrients and waste products
- Controls pH and water content
- Maintains body temp
- Hormones
- Immunity
- Coagulation
CBC Components
- RBC count
- WBC count
- Differential cell count
- HCT or PCV
- TP
- Platelet estimation / count
Light Source vs Magnification
Magnification is directly proportional to the degree of the light source
* low magnification = low light source
Microscope Parts
Condenser
Concentrates the light to obtain correct brightness for magnification
Microscope Parts
Iris Diaphragm
- Contained inside the condenser
- Used for quality of light control
- Opening diaphragm increases magnification
Microscope Parts
Revolving Objectives
Start exam on low power
* 4x = scan
* 10x = low power
* 40x = high power
* 100x = oil immersion (use oil sparingly)
HCT / PCV
Rough estimate of percentage of RBC in a given sample
Normal PCV
- Dogs: 45% (37-55)
- Cats: 37% (24-45)
Info Obtained from Spun PCV
- PCV Percentage
- TP
- Buffy Coat
- Plasma Color
- Microfilaria Check
Spun PCV
Microfilaria Check
- Place spun PCV tube on microscrope
- Focus just above buffy coat
- Will see them swimming here if positive
Buffy Coat
- Dividing point in a PCV tube
- Consists of WBCs and platelets
Buffy Coat Normal
Between 1-2% on reader
* increased = infection
* decreased = low WBC
Total Protein Normal
6.0 - 7.5 g/dl
PCV and Hydration Status
- Increases with dehydration
- Decreases with overhydration, renal dz, GI loss, liver dz
TP
Estimation of plasma protein alterations
* very basic and general interpretations only possible
Serum
Liquid portion of clotted blood
Plasma
- Liquid portion of whole blood
- Contains coagulation factors
Normal Serum Colors
- Clear = dogs, cats, and pigs
- Yellow = cows and horses
Serum Color
Hemolysis
- Is it real or not?
- Intravascular or extravascular?
Serum Color
Myoglobin
Brownish reddish color
Serum Color
Lipemia
Gives white color to serum
Plasma Color
Normal
Straw or Clear
Plasma Color
White
Lipemic due to eating prior to sample or hyperlipidemia (schnauzers)
* falsely elevates TP
* affects other serum chemistries
Plasma Color
Yellow
Icteric - liver / hemolytic dz
Plasma Color
Red / Pink
Hemolysis
* poor sampling
* intravascular hemolysis
PCV / TP Readings
Dehydration
- PCV = Increased
- TP = Increased
PCV / TP Readings
Anemic
- PCV = Decreased
- TP = Normal
PCV / TP Readings
Anemic w/ Dehydration
- PCV = Decreased
- TP = Increased
PCV / TP Readings
Protein Loss / Liver Dz / Burns
- PCV = Normal
- TP = Decreased
PCV / TP Readings
Abnormal Event
- PCV may remain stable for 6 hrs post trauma due to vasoconstriction and spleenic contraction
- TP will be the first to fall
RBC Parameters in CBC
- PCV
- RBC Count
- Hemoglobin (Hgb) Determination
- RBC Morphology
Determine RBC Count
PCV / 6
* label with ×10^6 /uL
RBC Normal Range
6-7 x 10^6 uL
Determine Hgb
PCV / 3
* label with g/dl
Hbg Normal Range
- Dogs: 12-18 g/dL
- Cats: 8-15 g/dL
