Blood Chemistry & Concentration Flashcards
What are some reasons for a blood chemistry panel?
Diagnose, monitor and screen possible diseases
What is the A/G ratio on a chemistry panel?
Albumin to globulin ratio
What is CPK on a chemistry panel?
Creatinine phosphokinase a muscle enzyme
What are some variables that can affect a chemistry panel?
- Pre-analytical which can occur before running a test
- Analytical which occur while the test is running
- Post-analytical which occurs after the test has been complete
What are some pre-analytical biologic variables?
- Inherent patient variables such as species, breed, age, and gender
- Controllable patient variables such as recent food ingestion, stress which releases cortisol and epinephrine, and exercise
What are some pre-analytical non-biologic variables?
Sample collection and handling
What are some analytical variables?
- Interference
- Assay performance
What kinds of interference can occur with analytical variables?
- Lipemia which can lead to volume displacement
- Hemolysis
- Icterus
- Hyperproteinemia
- Drugs
What are the post-analytical variables that can affect reference ranges?
- Human error
- Variations from one lab to another
What determines the reference ranges of a testing panel?
Usually determined from a population of healthy adult animals
What is another name for Gaussian Distribution?
The Bell Curve
What is the acceptance area of a bell curve?
Covers about 95% of the population
What is the rejection area of a bell curve?
It makes up 2.5% on the high end and low end because accepted ranges are determined by humans, therefore about 5% of normal animals may fall out of range
What is concentration?
The amount of solute contained in a certain amount of a solution
T/F: Concentration is a variable property
True
How can concentration of solutions be expressed?
- Volume percent
- Weight percent
- Weight/volume percent
What is the formula for determining volume percent?
Volume of solute/volume of solution x 100 = volume percent
What is the formula for determining weight percent?
Weight of solute/weight of solution x 100 = weight solution
What is the formula for determining weight/volume percent?
Weight of solutes (g)/volume of solution (ml) x 100 = weight/volume percent
What is colorimetry?
As light passes through a solution, light of a certain wavelength is absorbed by the colored chemical
What is the amount of light absorbed by a chemical directly proportional to?
- The concentration of the chemical that the light passes through
- The thickness, or path length, of the solution
What is Beer’s Law?
- A: absorbance
- I: intensity of transmitted light
- Io: intensity of incident light
What ways can concentration be determined?
- Beer’s law
- Proportionality
- Graphing
