Lab Med Flashcards
Plasma=?
Whole blood - RBC’s and wbc.
Serum=?
Everything not in the clot.
Lab med at UIHC includes what services? (Don’t mem, just review)
Lots. (chem, heme, immune, micro, molecular, transfusion, point of service, mailouts)
What comprises a basic metabolic panel?
electrolytes, BUN, creatinine, glucose
What falls under molecular category?
hereditary coagulopathies (not Heme department!), genetics, molecular infectious disease (not micro department!), oncology testing (not Heme department!)
Plasma should be used for what tests?
Most chemistry.
Serum should be used for what tests?
Serology (antibodies) & electrophoresis
Whole blood should be used for what tests?
CBC, heavy metals, imunosuppressants
I allow blood to clot, and take what’s left. This is?
Serum
I centrifuge blood, take the supernatant. This is?
Plasma
Red top tubes consist of what? Collect serum or plasma?
- Plastic with clot activators
- serum (recall serology, electrophoresis)
What are problems with red tubes?
microclots, must wait 30 min to clot (aided by inversion)
Serum separator tubes consist of? What color top? Clinical use?
- Basically a “red top” tube plus gel.
- Tiger
- Aspergillus galactomannan (avoids contamination from tube opening)
EDTA tubes have what added? What color top? Clinical use?
- Potassium-EDTA to prevent clotting (for plasma or whole blood)
- Pink
- CBC, sed rate, DNA, or drug tests
Plasma separator tubes have what added? Color? Use?
- Lithium heparin to prevent clotting and gel
- Green top
- metabolic panel and liver enzymes
What are the problems of plasma separator tubes?
Don’t use for lithium drug levels or “some assays”
What color top is a sodium citrate tube? Use? Problem?
- Blue
- coag tests!!
- Inadequate filling of tube (relative excess of anticoagulant)
Trace metal tubes are what color top? Use?
- “Royal” (dark) blue
- contain NO trace metals, so use for metal tests. (but can use regular EDTA tube for lead test)
What 2 priorities govern blood draw order?
1) Sterility
2) Additives
What is proper draw order for the KEY examples? (note some are left out)
citrate (for coag tests), serum tubes (red and tiger), plasma tubes (Li-Hep), EDTA (plasma or whole blood)
[This would be: blue, red, green, pink]
ACTH, ammonia, homocysteine, lactate, and cryoglobulin tests have what in common?
Add-on orders not allowed due to limited stability
Hemolysis causes what tests to increase in value?
AST, LDH, K, Hgb
Hemolysis causes what tests to decrease in value?
insulin
Lipemia (usually due to triglycerides) causes what problems?
- hemolysis
- low visibility for optical tests (can use pheresis to remove lipid plasma)
bilirubin/icterus causes what lab test problems?
spectrophotometry & common labs
What problems face genetic testing?
cost, monopolies, reimbursement
How are most tests reimbursed?
by diagnosis-related group (fixed amount for diagnosis regardless of number of tests or length of stay)
patients have a hard time getting authorization for in or outpatient tests?
out. (in just gets crazy w/ deductibles, etc)
Expensive tests are usually?
genetic to reference labs
T/F Genes can be patented?
False, but true for anyone other than Myriad Genetics
What does that mean?
T/F cDNA can be patented?
T (along w/ lab techniques)
monopolies are big evil people and stuff…. especially when it comes to genetic tests…
…that’s how he feels about them
Monopolies are illegal. This is unprecedented though. Never before has something that could be patented created an automatic monopoly for the time period of the patent. You can’t reverse engineer a DNA segment and then create a slightly different one. However, this doesn’t create a monopoly in the way business usually thinks about it. Diagnostic companies can only ‘monopolize one itty bitty segment’, but they still will have to compete. Fascinating!
What lab requires the patient only pay 20% of the test cost?
Athena
SCA (spinocerebellar ataxia) is unique why?
group of diseases, mostly auto dominant, most expensive test there is because of those monopolies
