Pre-Analytics Flashcards
What is a variable?
A factor that’s going to affect the outcome of test results & patient care
List 4 things that can affect how you choose a suitable venipuncture site?
- hematoma
- Edema
- Burns
- Scars
- Skin Conditions
- Occluded Veins
- Sclerosis
- Previous Mastectomy
- Tattoos
- IV Line
What can affect the success of a collection?
> Tourniquet time
Site cleansing
Blood flow
Defective supplies
Technique
Veins collapsing or rolling
What tests are affected by Lipemia?
electrolytes
LDH
hemoglobin
bilirubin
magnesium
- Ammonia
- Magnesium
- Lipase
- PTH
- Electrolytes
- TDM
Icterus samples affect which tests?
(Bilirubin in the cell)
Magnesium, Cholesterol,
Total Protein
- Lactate
- Cortisol
- Vitamin B12
- Ferritin
- Free T4
- PTH
- Ammonia
What are the 2 most common errors with Arterial Blood Gas samples?
Not storing on ice
Not delivering within 5-10 minutes
What is the forgiveness time for therapeutic drugs?
± 10-15 minutes
Know your special collections
What tests need to be kept on ice after venipuncture?
Ammonia
Homocysteine
What tests need to be kept warm after venipuncture?
Cold agglutinin
Cryoglobulin
How long do SST tubes need to sit before centrifuge?
3o minutes at room temp
How long do Lavender tubes need to sit before centrifuge and at what temp?
Refrigerate
spun within 4 hours at the lab
before that to give adequate time for lab
What are common issues faced in transportation of samples?
Time
Temperature
Light
What causes hemolysis?
- tourniquet left on or too tight (hemoconcentration)
- shaking tube
- alcohol not being dry
- improper storage or transportation
- tube unspun for too long
- incorrect needle
- incorrect volume for tube drawn
Hemolysis affects which tests most?
Potassium
LDH, AST, PTT
What causes icterus?
liver issues - viral, alcoholism, gallstones, cirrhosis, parasites
- hemolytic anemia
How can you eliminate contamination during a urine sample?
a midstream catch
Where is the most common place to store urine for preservation?
a refrigerator
If a urine sample is left overnight at room temperature, what changes can happen?
decrease in glucose and ketones
What are simple instructions for an FIT (Fecal Immunochemical Test) test?
- Place paper tissue between toilet seat lid and bowl
- Do your business
- Collect sample using grooves on the sample stick at the top of the sample tube
- Place back in the tube and twist closed
- Place in the ziplock bag provided and store in a refrigerator
Helicobacter Pylori Urea Breath Test steps are:
- Fast for 4 hours before your test:
-Do not smoke or eat anything, no fluid one hour before the test - Provide a breath sample
- Drink a lemon-lime solution
- Wait 30 minutes (do not smoke, eat, or drink during this time)
- Provide a second breath sample
For semen collection can the sample be brought in an hour after collection?
No.
Ideally 10-15 minutes after, but it can be 30 minutes after
What is the purpose of a centrifuge?
separation
to spin samples and separate cells
Can you put blood down the dirty sink?
No.
It has to get disposed of properly in a biohazard container