Blood Chemistry Testing

  1. What are the purposes for blood chemistry testing?
    • to evaluate organ-systems
    • to identify metabolic problems
    • to assist in diagnosis
    • to assist in prognosis
    • to monitor therapy
  2. What does "garbage in, garbage out" mean?
    you can run anything in the machine and the machine will give us numbers.  we have to make sure we are putting in the correct sample (whole blood, serum, plasma)
  3. Can you freeze whole blood?
    no, the cells with lyse when they defrost
  4. Which is better to use, heparin or EDTA?  Why?
    • heparin
    • it affects fewer test results
  5. What about the blood can affect the blood chemistry tests?
    • hemolysis
    • icterus
    • lipemia
  6. What does the term analytes mean?
    correct term for "blood chemistry"
  7. If we can't run a blood chemistry sample immediately, what should we do?
    label and refrigerate
  8. Once we collect the blood for a blood chemistry test, what do we do right away?
    • separate the cells
    • either centrifuge (for heparin) or let clot for 30 minutes (for serum)
  9. What can centrifugation do to the blood?
    may cause hemolysis if tubes are not balanced
  10. How long should we let the blood spin?
    at least 10 minutes
  11. What is the Stat spin?
    spins a smaller sample, faster
  12. What does hemolysis look like?
    red tinge to the plasma/serum
  13. If there is hemolysis, what will automatically increase?
  14. What can cause hemolyzed samples?
    • excess pressure during venipuncture/drawing the sample too fast
    • shaking the blood while mixing it
    • pushing the blood through a needle twice
    • putting the blood too fast in the tube
    • having moisture in the tube/syringe (from reusing syringes)
  15. What usually causes lipemia?
    mostly postprandial
  16. What are some diseases that may produce lipemia?
    • pancreatitis
    • hypothyroidism
  17. How do we avoid a sample being lipemic?
    fast the patient overnight
  18. What is ultracentrifugation?
    spins fast enough so that the fat in the blood settles in the bottom
  19. What are some common sources of error in testing?
    • sample problems
    • errors in technique
    • machine errors
    • clerical errors (interpreting numbers)
  20. What is the quality control we do for our blood chemistry machines?
    control and calibration
  21. What is control sera?
    a test we can buy that has a known value that we can run a control test on
  22. Are calibration and control the same thing?
  23. Do most blood chemistry machines calibrate themselves?
  24. Other than control and calibration of our machines, what else can we do to make sure our machines are working properly?
    split a sample, run half in house and send half out then compare results
  25. What is the main benefit of running blood chemistry tests in house?
    get fast results while the animal and client are still in the clinic to be able to start treatment right away which will help us practice better medicine because we will know what we are treating instead of making a guess while waiting for the blood work to come back
  26. What are stix tests?
    screening test like the glucometer
  27. What do stix tests mostly test for?
    BUN and glucose
  28. What kind of blood can we use for stix tests?
    whole blood
  29. Are stix tests fast?
  30. What are some examples of stix tests?
    • visidex
    • glucostix
    • petstix
    • azostix
    • quikchek
  31. Describe tablets.
    • mix sample on a tablet and look for a color change
    • not used often because few tests are available
  32. Are blood chemistry test machines expensive to buy?
  33. How do we choose which blood chemistry machines we buy for our clinic?
    • what tests do we want to be able to run
    • equipment investment (cost per test)
    • space available
    • technical help (some companies are better about providing technical help so are not)
  34. What are the three major blood chemistry manufacturers for veterinary medicine?
    • Idexx
    • Abaxis
    • Heska
  35. What was the first dry chemistry test from Idexx?
  36. Describe the VetTest.  Serum, whole blood, or plasma?  How much?  How many tests can be run?  How long until results?
    • serum
    • 10 microliters
    • 21 tests (slides)
    • 5 minutes
  37. Describe Idexx Catalyst Dx.  How many tests can be run?  Serum, whole blood, or plasma?  How many clips are preloaded?
    • 27 tests
    • serum or plasma
    • 6 preloaded clips
  38. What are the special tests that the Catalyst Dx can run that other machines can't?
    • Lactate
    • NSAID panel
    • Urine protein:creatinine ratio
  39. What does the urine protein:creatinine ratio test?
    assesses protein loss
  40. What does the VetStat test for?
    runs electrolytes and blood gases
  41. What clinics do we usually see the VetStat in?
    equine and emergency clinics
  42. Describe Scil Reflovet Plus.  What sample (whole blood, serum, plasma)?  What is used to test?  How many tests can be run?  How much blood is needed? How long do tests take?
    • can use whole blood, serum, and plasma
    • single test strips
    • 15 tests can be run
    • 30 microliters
    • 2 - 3 minutes
  43. Describe the Scil Spotchem EZ.  How many tests can be run?  What can be used for the sample?  What is used to test?
    • 19 different tests, 9 can be run at once, offers 6-test multistrip
    • Serum, plasma, whole blood
    • strip (look like urine strips)
  44. Describe Dri-Chem 7000.  What does it use to test?  How many tests can be run?  How long does it take to run a test?
    • slides
    • can run single tests or 5 panels at a time
    • 5 panels takes 16 - 30 minutes
  45. Describe VitalPath.  What does it test?  How much blood do you need for the sample?  What can be used (whole blood, serum, plasma)?  How long does it take to run a test?
    • blood gas and electrolyte analyzer
    • 60 microliters
    • whole blood, serum, and plasma
    • takes 50 seconds to run 35 parameters
  46. How many blood chemistry machines does Abaxis offer?  What are they?
    • 2
    • Vetscan i-Stat 1 and VetScan (Classic, VS2, and VSpro)
  47. Describe Vetscan i-Stat 1.  How many tests can be run?  What does it use to test?  Whole blood, plasma, or serum?  How long for results?  What does it test for that other machines don't?
    • 1 - 12 tests per cartridge
    • cartridges
    • whole blood
    • 2 minutes
    • blood gases
  48. What kind of clinic is the Vetscan i-Stat 1 mostly used in?  Why?
    • wildlife and large animals
    • it is handheld and can go out in the field
  49. Describe VetScans (classic, VS2 and VSpro).  How many tests can be run?  What is used to run tests?  How much blood is needed?  Whole blood, serum, plasma?  How long does it take to get results?
    • 23 tests
    • rotors
    • 100 microliters
    • whole blood
    • 15 minutes
  50. What do blood gases analyze?
    • pH
    • pO2
    • pCO2
    • HCO3
    • p stands for pressure
  51. When we run the blood gas machine, where do we get the blood?
    whole arterial blood
  52. How do we keep the blood sample when we are testing blood gases?  Why?
    • keep it cold
    • to prevent RBCs from converting O2 into CO2
  53. When we are running a blood chemistry, what are we looking for?
    an increase or decrease of values for specific organs
  54. How do we know which blood chemistry tests to run?
    evaulate the patient's history and clinical signs
  55. What are routine blood chemistry tests that we run for non-sick patients?
    • preanesthesia
    • geriatric profile
  56. Image Upload 1
    Catalyst Dx
  57. Image Upload 2
    Dri-Chem 7000
  58. Image Upload 3
    Scil Reflovet Plus
  59. Image Upload 4
    Spotchem EZ
  60. Image Upload 5
  61. Image Upload 6
  62. Image Upload 7
  63. Image Upload 8
  64. Image Upload 9
  65. What is the functions of a kidney?
    • remove nitrogen waste
    • regulate salt ions
    • regulate acid-base balance
    • regulate RBC production in bone marrow
    • regulate blood pressure
    • conserve blood glucose
    • elimination of drugs/toxic substances
  66. Define azotemia.
    an increase in nitrogenous waste (BUN, creatinine) in the blood
  67. What can an increase in nitrogenous waste (BUN, creatinine) be?
    • prerenal azotemia
    • renal azotemiz
    • post-renal azotemia
  68. Azotemia occurs when _____ of the glomerulus stops working.
  69. What does GFR stand for?
    glomerulus filtration rate
  70. What causes prerenal azotemia?
    kidneys are not getting perfused.
  71. What are some clinical signs of prerenal azotemia?
    • dehydration
    • show
    • heart disease
    • urine SG increased
  72. What does it mean "kidneys are not getting perfused"?
    blood is not coming to the kidneys like it should
  73. Is GFR increased or decreased with prerenal azotemia?
  74. Are BUN and creatinine values increased or decreased with prerenal azotemia?
  75. What will happen if prerenal azotemia is not treated?
    will turn into renal azotemia
  76. How do we treat prerenal azotemia?
    give fluids
  77. Once we increase perfusion to the kidneys, will prerenal azotemia go away and the BUN and creatinine values go back to normal?
  78. What is renal azotemia?
    • kidneys are being destroyed
    • chronic renal disease
  79. What percent of the nephrons are non-functional with renal azotemia?
  80. When does renal azotemia occur?
    • usually occurs after lose ability to concentrate urine
    • specific gravity isosthenuric (same as blood)
  81. Renal azotemia leads to what?
    renal shutdown and the patient dies
  82. What usually causes postrenal azotemia?
    • urinary blockage or post-renal leakage
    • blocked urethra or ruptured bladder
  83. If we don't fix postrenal azotemia what will happen?
    the patient will die
  84. If we unblock the patient, will postrenal azotemia go away?
    yes, as long as there is not permanent renal damage
  85. What kind of patient do we commonly see postrenal azotemia?
    in blocked cats
  86. What is uremia?
    • increased BUN and creatinine and patient is very sick
    • older term for azotemia
  87. What should the kidneys eliminiate that they don't which causes an increased BUN?
  88. Where is in the kidney is the urea filtered?
    in glomerulus
  89. Passive tubular reabsorption should absorb how much urea?
  90. The longer filtrate is in the tubules, the _____ will be reabsorbed.
  91. GFR is dependent on _____
    renal perfusion
  92. _____ perfusion causes _____ GFR with causes urea to stay in the blood
    • decreased
    • decreased
  93. The _____ perfusion, the longer it will take to pass thru tubules which causes _____.
    • less
    • more reabsorbed
  94. What kind of sample do we use for azostix?
    whole blood
  95. What kind of sample do we need to test BUN in machines?
    serum or plasma
  96. What will lipemia do to BUN values?
    falsely elevate BUN values
  97. What kind of contamination will cause an increase in BUN?
    urease-producing bacteria
  98. How is creatinine formed?
    be degradation of creatine
  99. Creatine comes from what?
    muscle - energy source
  100. Where is creatinine filtered?  Is there any reabsorbtion/
    filtered at glomerulus, no tubular
  101. What is a more accurate measurement of GFR, BUN or creatinine?
  102. When creatinine is increased, is the prognosis good?
    no, it is harder to decrease and prognosis is poor
  103. What kind of sample do we use to test for creatinine?
    serum or plasma
  104. What can falsely elevate creatinine levels?
  105. What is phosporus?
    a mineral
  106. Where is phosporus filtered?
    normally freely filtered at glomerulus
  107. Decreased GFR will _____ phosporus.
  108. What will phosporus do when there is renal disease?
  109. What often happens with non-regenerative anemia?
    chronic renal failure
  110. Why does chronic renal failure cause non-regenerative anemia?
    • because of the decrease production of erythropoietin
    • GI ulceration/bleeds and will decrease RBC lifespan due to azotemia
    • bone marrow is also suppressed
  111. What causes hypoalbuminemia?
    loss of albumin at glomerulus
  112. When there is hypoalbuminemia what kind of protein do we see in the urine?
    increase in protein
  113. When there is renal disease there is _____ of albumin
    increased loss
  114. What is the largest gland in the body?
  115. What is cell necrosis of the liver?
    break down of liver cells
  116. What is cholestasis?
    slowing of passage of bile
  117. What kind of problems can cause jaundice/icterus?
    liver or hemolysis problems
  118. If you have enough hemolysis to cause icterus then the patient will be _____.  What kind of test can we use to rule this out?
    • anemic
    • PCV
  119. What is total bilirubin?
    the amount of indirect (unconjugated) and direct (conjugated) bilirubin added together.
  120. If there is an increase in indirect (unconjugated) bilirubin, what does that mean?
  121. If there is an increase in direct (conjugated) bilirubin, what does that mean?
    liver disease
  122. What can total bilirubin cause?
  123. What is conjugated bilirubin?
    bilirubin made water soluble in order to be secreted in the urine
  124. What kind of bilirubin do most blood chemistry tests test for?
    total bilirubin
  125. What is stercobilinogen?
    gives us the brown color of feces
  126. Increased bilirubin will cause increased _____.
  127. Which test is better for testing liver disease, bilirubin or bile acids?
    bile acids
  128. Bile acids tells you something is wrong with the liver, but what does it not tell you?
    what is wrong with the liver
  129. Bile acid is _____ in most liver disease.
  130. What do ammonia tests test for?
    liver-brain syndrome (aka hepatic encephalopathy)
  131. When do we see increased ammonia tests?
    porto-systemic shunts
  132. What will a clinical sign most likely be with dogs with porto-systemic shunts? 
  133. Why is ammonia increased with port-systemic shunts?
    liver is not converting the ammonia to urea and is getting in the brain
  134. What are some reasons why enzymes can be increased?
    • muscle necrosis
    • bone activity
  135. What are the different enzymes we test for?
    • sALT
    • sAST
    • sAP
    • GGT
    • SD
  136. Which enzyme is most useful to test for liver disease in dogs and cats?
  137. Which enzyme will be increased with a swollen liver?
  138. Which enzyme will be increased due to an increase in muscle activity?
  139. Which enzymes increase with cholestasis?
    • sAP
    • GGT
  140. What is the BSP clearance?
    only test that tests live function and tells how much the liver is functioning at that specific time
  141. How do you do the BSP clearance test?
    inject dye IV then collect the blood after 30 minutes
  142. Where is cholesterol synthesized?
    primarily by the liver but can be distributed elsewhere
  143. What are some things that would cause cholesterol to increase?
    • endocrine abnormalities
    • postprandial lipemia
    • hepatic disease
    • renal disease
  144. Where is cholesterol produced?
    in the liver
  145. Which enzymes are in the exocrine pancreas?
    • amylase
    • lipase
    • trypsin
  146. What causes amylase and lipase to increase?
    • cell necrosis
    • pancreatitis
  147. What is amylase?
    enzyme that breaks down startch
  148. What is lipase?
    enzyme that breaks down fat
  149. What is trypsin?
    enzyme that breaks down protein
  150. When will trypsin be decreaed?
    with atrophy
  151. How do we measure trypsin?
    • in feces
    • x-ray film test - stick x-ray film in watery diarrhea, if the x-ray film turns clear then there is trypsin present
  152. What does the endocrine pancreas do?
    • regulates glucose
    • makes insulin
  153. Which pancreas enzymes should be run together?
    amylase and lipase
  154. What is the Serum Trypsin-like Immunoreactivity Test (TLI/STLI)?
    determines pancreatic insufficency by detecting trypsinogen in serum.
  155. What do low values of the Serum Trypsin-like Immunoreactivity Test indicate?
    reduced pancreatic mass
  156. Where is amylase found?
    pancreas and duodenum and saliva
  157. If amylase is increased what does that mean?
    • pancreatic leakage (pancreatitis)
    • renal failure
    • GI disease
    • hepatobiliary disease
  158. What can affect the results of an amylase test?
    • hemolysis falsely elevates
    • lipemia may reduce
  159. Where is lipase found?
    • pancreas
    • gastric mucosa
  160. How is lipase eliminated from the body?
    by the kidneys
  161. What kind of tube should we avoid when collecting blood to test for amylase and lipase?
    EDTA (purple top)
  162. What can decrease lipase levels?
    hemolysis and lipemia
  163. What is CK (CPK)?
    enzyme in the muscles
  164. When does CK enyzme increase?
    degenerative/necrotizing muscle injury:  myositis, IM injections, poor venipuncture, vigorous exercise, electric shock
  165. Is CK a very stable enzyme?
  166. What does CK stand for?
    creatine kinase
  167. What other enzyme is found in muscle?
  168. What can cause CK to be falsley elevated?
    • EDTA
    • citrate
    • sunlight
    • oxidizing agents
    • delay in assay
  169. Is it a problem if glucose is increased or decreased?
  170. How can we test glucose?
  171. Can the signs for hypoglycemia and hyperglycemia be similar?
  172. If a patient is fasted, the glucose test using capillary blood is _____ than venous blood.
    2 - 5 mg/dl
  173. If post-prandial, the glucose test using capillary blood is ____ than venous blood.
    20 - 70 mg/dl
  174. What is frutosamine?
    • glycated serum protein
    • reflects glucose over the past 2 - 3 weeks
Card Set
Blood Chemistry Testing
Lab Tech ll