Card Set Information
Specimen Collection Control Quiz
Specimen Collection & Quality Control Quiz
What 4 things does an accurate chemical analysis depend on?
perservation of sample
processing of sample
method of analysis
all are equally important
What is the idea time for lab measurements to be performed?
Within 1 hr
Why are specimens preserved?
1. so the substance will not be altered
2. specimens collected in a timely sequence should be stored until they can be analyzed at the same time
3. samples retained or kept long enough to repeat if necessary
What sample is most often used for chemical analysis?
*preferably fasting serum*
What is the differance between serum and plasma?
1. Serum is liquid portion with fibrinogen and clotting factors removed.
2. Plasma is liquid portion of the circulating blood and it contains fibrinogen and clotting factors.
What methods are used to preserve specimens?
1. Part of specimen collection- sodium fluoride is the preservative in the gray top tube.
2. We can refrigerate specimen, but must be brought to RT before testing.
3. Separating the cells from the serum & plasma (the gold tube is usually used for separation)
4. There are special requirements - ie. protect bilirubin from light.
5. Freeze serum or plasma
What is the silicone barrier used for?
To separate serum or plasma from cells.
Usually gold top tubes are used, the jell in the bottom of tube is (thixotropic gel).
1. The jell prevents the shift of substances.
2. It also prevents glycolysis.
What vacutainer is used to collect serum and why?
Gold top or red top tubes have no anticoagulant in the tubes.
How is a gold top tube processed?
1. inverted 5 times- do not remove stopper, or centerfuge imediately after drawing
2. allow to clot upright- at least 30 mins. no more than 60 min.
3. centerfuge at least 15 min. within 1 hr. of collection
4. transfer to a labeled plastic screw cap vial
5. Refrig (cool) or freeze
What are the precautions when handling blood?
2. open stopper carefully away from you
3. disinfect blood spills immediatly with 10% bleach or disinfectant
4. discard tubes and sharps in crush & leak proof container
a clear red color to the serum or plasma
Icteric or (hyperbilirubinemia, jundice)
brownish yellow, patient may have jaundice or hepetisis
the serum or plasma is milky white
the true or actual size
average results of healthy individuals
Batch or run
Specimen analyzed at the same time.
ex. a batach of cookies
Calibrator used to set machine values
ex. alarm clock
Must fall within acceptable range before patient value reported
One of the specimens in the batch is measured twice and it check precision
Specimens are sent to your lab
You analyze samples and send the results.
The agency will let you know how you did and how you compared to other labs
*meap testing for labs*
What does a quality control program include?
1. standards or calibrators
4. profenecy service
What 4 things does the control check for?
1. machine or instrument
2. reagents, strips, test cards, and starting manual
4. environment temp. and humidity
What steps should follow if a control fall outside of the acceptable range?
1. document it ( in lab log)
2. check everything
3. retest the same control vial
4. retest new vial
5. recalirbrate the machine
6. call customer service
What is great about fasting?
reflects metabolic base line
avoids lipema (which is fat in blood)
1. Use universial precautions pooled serum/plasma
control may have human antigens.
2. Unopened exp. date, midnight, last day of month opened.
ex. 2011-07 is July 31, 2007 at midnight
3. Results reported according to lot #
4. Keep QC results 2 years
5. CLIA wavied quality contrl testing according to manufacturers instruction. (clia has 3 levels of testing. waived, moderate and high)