Pre-Analytics Mid-Term Flashcards
Urine Analysis Non-Blood Specimens Equipment and Safety
What integrity issue is this?
Hemolysis - red blood cells have burst
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 Integrity issue is this?
Icterus - increased Bilirubin in cell
What causes icterus?
liver issues - viral, alcoholism, gallstones, cirrhosis, parasites
- hemolytic anemia
Which tests are most affected by icterus?
Magnesium, Cholesterol, Total Protein
What integrity issue is this?
Lipemia - fat in sample
What causes lipemia?
too much fat in bloodstream
fatty meal
hereditary
cholesterol
triglycerides
What tests are most affected by lipemia?
electrolytes
LDH
hemoglobin
bilirubin
magnesium
What does a 3 day (72hr) fecal collection container look like or resemble?
A paint can
What is urine for a pregnancy test collected in?
Sterile container (orange or blue top)
What is a 24hr urine sample collected in?
A large orange container (about 4L)
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
List 3 things you need to avoid 3 days before collecting samples for a Fecal Occult Blood Test (FOBT)?
- red meats,
- raw fruits,
- vitamin C (fruits and supplements in high doses),
- antacids,
- iron supplements
- medications to stop diarrhea
Can you list the main steps in a Fecal Occult Blood Test (FOBT)?
- Use applicator stick with fecal sample to smear on window area A
- Smear a second sample on window area B
- Throw out stick
- Cover Hemoccult slide and place in envelope
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
How long is a lactose tolerance test?
2 hours
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 are the timelines for a patients last ejaculation before they can collect a semen sample?
No less than 48 hours, no longer than 7 days
What household item is parafilm similar to?
Saran Wrap
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
What is a pipette used for?
measuring small samples accurately
When would you use a fume hood?
When using chemicals you don’t want to inhale
What do you use an incubator for?
growing samples of microorganisms or bacteria
What is the major difference between a Fume Hood and a Biological Safety Cabinet?
The Biological Safety Cabinet is not vented to outside because the air goes through a hepa filter.
The Fume Hood is vented to outside.
How often does lab equipment need to be maintained/calibrated?
Every 6 months usually
Yearly for a full service
What does CSF stand for and how many sample tubes are usually collected?
Cerebrospinal Fluid
Minimum 3 tubes
When is the best time to collect urine for cytology?
Ideally, first morning void
Which fecal test uses a chemical indicator/reaction method?
Fecal Occult Blood Test (FOB)
Which fecal test uses an antibody method?
Fecal Immunochemical Test (FIT)
What are anaerobic organisms in urine?
Anaerobic bacteria are rare agents of urinary tract infections (UTIs)
What is a refrigerator’s temperature kept between?
2º - 8º C
What are 2 reasons we collect urine samples?
- diabetes diagnosis
- kidney disease
- pregnancy test
- cytology (to screen for cancer)
- disease progression
- Chlamydia and Gonorrhea
- creatinine Clearance (kidney function)
- toxicology (drug screening)
- electrolytes
- Albumin
- Culture and Sensitivity (C & S)
What are 3 reasons a specimen would be rejected?
- discrepancy between labels
- unlabelled
- incorrect container or expired container
- insufficient amount
- incorrect time of collection
- improper collection
- incorrect storage or transportation
- leaky container
What is plasma?
Blood fluid containing clotting factors
- requires anticoagulants
What is serum?
Blood fluid without clotting factors
- What remains after the blood has clotted
- does not require anticoagulants
What tests are most affected by hemolysis?
- PTT (Patial Thromboplastin Time)
- Potassium
- LDH (Lactate Dehydrogenase)
- AST (Aspartate Aminotransferase)
