(P) Lec 2: Specimen Collection + Specimen Handling (Part 2) Flashcards
TOF: Fasting is required in hematology
False
CLSI states that you should never combine tubes, holders, and needles from different what?
Manufacturers
A sudden change in position during blood draw can cause what?
Hemoconcentration or Hemodilution
How high should you apply the tourniquet from the puncture site?
7.5 - 10cm or 3-4 inches above
What should the BP cuff pressure be as an alternative to a tourniquet?
60mmHg (pump 1-2 times)
What kind of tubes are strongly recommended for medication levels?
Glass Tubes
Plastic/glass serum tubes should never be used before what?
Coagulation Tubes
What disinfectant is used for routine blood tests?
Isopropyl
What disinfectant is used for routine bacteriological tests?
Iodine
What disinfectant is used for alcohol determination?
Benzalkonium chloride
Fist pumping during blood draw causes what?
Hemoconcentration
What should be the needle angle upon entry?
15-30 degrees
A small-bored needle has a greater chance of producing a sample that has undergone?
Hemolysis
When doing the ETS method, when do you remove the tourniquet?
When all tubes are filled
When doing the ETS method, you are to remove the tourniquet before what?
Withdrawing the needle
This SOP prevents additives from carrying over
Order of draw
How long should you apply pressure on the puncture site?
3-5 minutes; maximum of 15 minutes
What size of gauze pad is ideal to use when applying pressure?
2x2
After sanitizing, no traces of alcohol should remain as this can cause what? (2 answers)
- Hemolysis
- Contamination of glucose testing
New studies show that what kind of cleaning motion is now better than circular motion?
Back and forth
No. of inversions: Clot Activator
5
No. of inversions: Sodium Citrate
3-4
No. of inversions: Heparin
8
No. of inversions: EDTA
8
No. of inversions: Sodium Fluoride
8
How long should you bandage the puncture site for?
15 minutes to 1 hour
Patients should not bend the arm in this manner after blood draw
Upward
If bleeding lasts for more than how many minutes, inform the nurse or supervisor
1 minute
This phase refers to all steps taken before actual testing (specimen handling, processing, collection, patient identification, material preparation, etc.)
Pre-analytical phase
What are the alternative names for the 3 phases?
> Pre-analytical
> Analytical
> Post-analytical
> Pre-examination
Examination
Post-examination
This refers to the combination of the pre-analytical phase, analytical phase, and post-analytical phase
Quality Assurance
This makes sure that all procedures in the lab will be done properly from specimen collection up to the reporting and recording of results
Quality Assurance
Refers to factors that alter test results that are introduced into the specimen before testing (+ before and during collection, and during transport, processing, and storage)
Pre-analytical errors
This phase refers to actual testing/test performance (all procedures that belong to the method of measurement)
Analytical phase
This phase comes after the test performance (reporting, interpolation, recording, and relaying of results to the physician)
Post-analytical phase
This is an important pre-analytical error (example stated in the reclec)
Improper handling of specimen that could result in erroneous, misleading, delayed results, and incorrect care of the patient
What are the 3 controllable pre-analytical variables?
- Physiologic
- Lifestyle
- Drug administration
Pre-analytical variables
It means you can do something about this factor (a form of intervention)
Controllable variables
Pre-analytical variables
It means you cannot do anything about this factor
Non-controllable variables
What are the 4 non-controllable pre-analytical variables?
- Biological influences
- Environmental factors
- Long-term cyclical changes
- Underlying medical conditions
Non-controllable pre-analytical variables
Age, sex, and race
Biologic
Non-controllable pre-analytical variables
Altitude, ambient temperatures, and place of residence
Environmental factors
Non-controllable pre-analytical variables
People living in high-altitudes have this important body substance comparatively decreased compared to those in low-altitide areas
Oxygen level
Non-controllable pre-analytical variables
This variable expands plasma volume which causes a significant decrease in plasma protein when being measured
Heat
Non-controllable pre-analytical variables
Seasonal influences and menstrual cycles
Long-term cyclical changes
Non-controllable pre-analytical variables
Fever, shock, trauma, and blood transfusion
Underlying medical conditions
Non-controllable pre-analytical variables
This underlying medical condition provokes many hormone responses which could affect certain analytes in blood
Fever
Patient preparation
This factor affects skeletal muscle enzymes (these increase when this activity is done); prone to produce false positive results
Exercise
Patient preparation
A state wherein the blood is collected early in the morning before rising
Basal State
Patient preparation
The basal state requires what type of patient preparation method?
Fasting
Patient preparation
If your glucose is being requested for testing, how many hours do you need to fast?
6-8 hours
Patient preparation
If your lipid profile (TAG, HDL, and LDL) is being requested for testing, how many hours do you need to fast?
10-12 hours (max. of 14)
Patient preparation
If both your glucose and a lipid profile are being requested for testing, how many hours do you need to fast?
8-12 hours
Patient preparation
Refers to when people eat high-protein foods, sugary foods, are vegetarian, drink coffee regularly, etc.
Diet
Patient preparation
Bananas and tomatoes increase the production of what metabolyte of serotonin?
5HIAA (5-Hydroxyindoleacetic acid)
Patient preparation
This kind of diet could result to an increase in urea and creatine in the blood
High-protein
Patient preparation
A sudden position change or prolonged stagnation can result to 2 events, which are?
- Hemoconcentration
- Hemodilution
Patient preparation
These 2 activities (lifestyle-related) need to not be done 24 hours before collection because it can affect the analytes in the serum
Tobacco smoking and Alcohol ingestion
Your physiologic variation is aka?
Circadian Rhythm
Identify if these analytes are highest in the morning or night
- Iron
- Potassium
- Renin
- Cortisol
- Insulin
- Aldosterone
Morning
Identify if these analytes are highest in the morning or night
- Growth hormone
- Testosterone
- TSH
- Prolactin
Night
How many gentle tube inversions are needed depending on the additive present, type of tube, and manufacturer?
3-10
This process allows the even distribution of the additives present in your tubes
Tube inversion
Inadequate mixing is not ideal as this can result in what?
Microclots
If there is inadequate mixing when using a gel separator tube, what can happen to the sample?
Incomplete clotting
TOF: Non-additive tubes still require mixing
False
Tubes should be transported with the stopper facing where?
Upwards
This practice reduces sample agitation, it aids in clot formation, and prevents contact of tube contents with the stopper
Transporting tubes with the stopper up
What kind of specimen gets transported like this?
Put in a plastic bag with a biohazard logo, liquid-tight closure, and slip pocket for paperwork
Blood specimens
What kind of specimen gets transported like this?
Use leak-proof containers
Non-blood specimens
What kind of transport system is this?
To be protected from shock and sealed in a zipper type plastic bag to contain spills
Pneumatic tube system
If blood samples are allowed to clot within 20-30 minutes, it should arrive in the lab how many minutes upon collection?
45 minutes
Once a blood sample has arrived in the lab, you must separate the serum with the cell within how many hours upon collection?
1 hour (CLSI states the maximum to be 2 hours including the 45-minute allowance for transport and the 20-30 minute allowance to clot)
There should be no delay in sample delivery to minimize the effects of what?
Metabolic processes (e.g. glycolysis and cellular metabolism)
Temperatures related to specimen handling
36.4 to 37.6 degrees
Body Temperature
Temperatures related to specimen handling
15 to 30 degrees
Room Temperature
Temperatures related to specimen handling
2 to 10 degrees
Refrigerated Temperature
Temperatures related to specimen handling
-20 or lower
Frozen Temperature
These analytes require which procedure?
- Gastrin
- Ammonia
- Lactic Acid
- Catecholamines
- Pyruvate
- PTH
Chilling (can be freezer or refrigerator temperature)
Special handling
This method can slow down the metabolic proccesses and protects the analyte even when there is delay
Chilling of specimen
Special handling
What equipments can you use to transfer specimen via chilling (refrigerator temperature)?
- Ice
- Ice packs
- Crushed ice together with water
Special handling
What equipments can you use to transfer specimen via chilling (freezing temperature)?
- Solid CO2
- Nitrogen gas
Special handling
What equipments can you use to transfer specimen via room temperature (37ºC)?
- Heat blocks
- Heel warmers (40-42ºC)
Special handling
If a sample is ordered to be transported anaerobically, what should be absent? (for ABG and ionized and non-ionized calcium)
Oxygen
Special handling
These produce an inadequate cooling effect on the sample
Large ice cubes
Special handling
What happens when there is direct contact between the sample and solid ice?
Hemolysis/analyte breakdown
These analytes require which transport procedure?
- Cold agglutinins
- Cryofibrinogen
- Cryoglobulins
Transport at 37 degrees (should also be pre-warmed prior to transfer)
These tests require what handling procedure?
- Bilirubin
- All Vitamin Levels
- Beta carotene
- Porphyrins
- Folate
Protection from light (sunlight and artificial)
What methods can you employ to protect your sample from light?
- Wrap in aluminum foil
- Use amber-colored microcollection tubes
One must not discard a specimen until who are notified?
Physician or nurse
In chemistry, reject the sample if it is what? (2 answers)
- Hemolyzed
- Quantity is not sufficient
How do you know if your specimen is hemolyzed?
After centrifugation (or standing), the color of the plasma is pink or red
In hematology, reject the sample if it is what?
Clotted
This is a machine that spins blood and other specimens at a high number of revolutions per minute
Centrifuge
This causes the cells and plasma or serum in blood specimens to separate
RPM/RCF (relative centrifugal force)
What gravitational force setting should be done for a centrifuge?
850-1,000 GF for 10-15 mins OR 1,000-3,000 RCF for 10 mins.
If one removes the tube stopper, what analyte is lost and what is increased? (2 answers)
- CO2 is lost
- pH is increased
This should remain on tubes to prevent contamination, evaporation, aerosol formation, and pH changes
Stoppers
Specimen awaiting centrifugation can be contaminated by what 2 possible contaminants?
- Sweat
- Powder from gloves
A specimen should never be centrifuged more than how many times?
Once
This improper use of the centrifuge results in hemolysis and analayte deterioration, which alters test results
Repeated centrifugation
A centrifuge generates what during operation?
Heat
Specimens requiring chilling should be processed in what kind of centrifuge?
Temperature-controlled refrigerated centrifuge
When can you open the lid of a centrifuge after centrifugation?
After the rotors have stopped
Blood must be completely what before centrifugation?
Clotted
Complete clotting happens within how many minutes at RT?
30-60 minutes
SST and tubes with clot activators take how long to completely clot?
30 minutes
Thrombin (activates clotting) tubes take how long to completely clot?
5 minutes
If there is incomplete clotting, there is the formation of what?
Fibrin
When one is on anticoagulant medication, does it take longer or shorter to clot?
Longer time
The use of what applicator stick for rimming the sides of the tube is not recommended?
Wooden
When using a thixotropic gel separator (gold top) tube for centrifugation, what layers are generated in the tube after centrifuging?
- Serum on top
- Buffy coat (sometimes absent)
- Gel in the middle
- Blood cells on the bottom
What is the specific gravity of the thixotropic gel once it has been centrifuged and placed between the serum and blood cells?
1.04
What tests commonly require a plasma specimen collected in a citrated tube?
Prothrombin Time (PT) and Activated Thromboplastin Time (aPTT)
TOF: When it comes to PT and aPTT, you do not need to separate the plasma from the cells as this has no effect
True
To prevent or minimize aerosol spray or blood spray, the stopper should be pulled in what manner?
Straight up and off; not “popped off” using a thumb roll technique
Refers to the portion of specimen that is used for testing
Aliquot
Refers to when multiple tests are ordered using a single specimen; using different specimen in different areas of the laboratory
Aliquot Preparation
This is prepared by transferring a portion of the specimen into one or more tubes
Aliquot
When transferring aliquots, what kind of pipettes are to be used?
Disposable transfer pipettes (Pasteur pipettes)
TOF: You may pour serum or plasma
False (causes increased risk for aerosol formation and splashing)
TOF: Centrifuge the sample 1 hour after collection
False (immediately after collection)
Never put these 2 together when they use different anticoagulants in the same aliquot tube
Plasma and Serum
Which organization stated this: “all procedures involving blood or potentially infectious materials shall be performed in such a manner as to minimize splashing, spraying, splattering, and generation of droplets of those substances“
OSHA
When performing this venipuncture method, it is common to see slightly overfilled tubes
ETS (you cannot predict the vacuum)
A hemolyzed sample shows up as red/pink which indicates the presence of what?
Hemoglobin
If your hemolyzed plasma/serum is red, how much hemoglobin is present?
100mg/dL
If your hemolyzed plasma/serum is pink, how much hemoglobin is present?
20mg/dL
A milky appearance of serum can be due to high levels of what?
Triglycerides
TOF: A patient’s plasma sample appears milky (which indicates excess triglycerides) even after they’ve fasted correctly, do you reject the sample or not?
No (it is an indicator that something is wrong interiorly and should be investigated)
TOF: A patient’s plasma sample appears dark yellow (even though it should be clear to pale yellow), do you reject the sample or not?
No (it means that bilirubin is increased; icteric sample)
What could be a reason for why there is increased lipid content in plasma that is turbid?
Whenever there is inadequate fasting due to chylomicrons