(M) Lesson 5: Specimen Handling and Processing of Blood Specimen Flashcards
What are the three analytical phases inside the laboratory?
Preanalytical, Analytical, Postanalytical
T or F; The quality of laboratory results does not depend on the proper handling
False
What percentage of error occur prior to analysis?
46 - 68%
Most serious and potentially most dangerous pre-analytical error
Improper patient identification
Fasting hours for GGT
8 - 10 hours
T or F; you can use alcohol in blood alcohol testing as an antiseptic
False
Correct degrees for venipuncture needle position
15 - 30 deg
Standard bore size for kids
23 (blue)
Additive for (light) blue-coded vacutainer and for what test
Sodium citrate, coagulation studies
Additive for lavender-coded vacutainer and for what test
EDTA, Hematology
Additive for green-coded vacutainer and for what test
Heparin, Chemistry
Additive for gold and/or orange-coded vacutainer and for what test
Clot activator, Chemistry
Additive for red-coded vacutainer (plastic) and for what test
Clot activator, Chemistry
Additive for gray-coded vacutainer and for what test
Sodium fluoride, Chemistry
Additive for red-coded vacutainer (glass) and for what test
None, Chemistry
Recite the correct order of draw
- Sterile blood culture tubes – Yellow stopper
- Coagulation tubes – Light blue stopper
- Serum tube / Plain tube – Red stopper
- Heparin tube – Green stopper
- EDTA tube – Lavender / Purple stopper
- Anti-glycolytic tube / Fluoride – Gray stopper
“Stop, Light is Red. Green Light, Go. “
“Stop, Light is Red, Stay Put. Green Light, Go.”
What is the result of filling the vacutainer with less blood?
Dilution effect
What is the result of filling the vacutainer with too much blood?
Blood clots
What is the blood to anticoagulant ratio?
9:1
T or F; it is fine to combine 2 partially filled tubes
False
T or F; It is fine to send the partially-filled tube to the lab if the patient is no longer available
True
It is when the liquid enters the tissue
Hemoconcentration
It is when fluid goes outside the tissue
Hemodilution
T or F; Longer tourniquet application causes decreased pH, increased potassium, and decreased calcium and magnesium
False (lowered pH, increased potassium, INCREASED calcium and magnesium)
T or F; You can mix non-additive tubes
False (causes hemolysis)
What forms when there is an inadequate mixing of tubes with additives?
Micro-clot formation
What forms when there is an inadequate mixing of tubes with gel separation?
Clotting may be incomplete
How many inversions for EDTA?
8 - 10x
How many inversions for citrate tube?
3 - 4x
How many inversions for SST?
4 - 5x
How many inversions for heparin?
8 - 10x
How many inversions for flouride?
8 - 10x
What would rough handling and agitation cause?
- Hemolysis
- Activation of platelets that could affect coagulation tests
- Break glass types
These are tubes wrapped in absorbent package material and placed in a self-sealing bag with biohazard emblem
Primary container
These are bag or box for placement of samples
Secondary container
Compartments of primary container
- Sample
- Requisition form
T or F; Samples from different patients can be placed in the same bag
False
System that propels cylindrical containers through networks of tubes by compressed air or by partial vacuum
Pneumatic Tube System or Pneumatic tube transport (PTT)
T or F; PTT is more traumatic and can cause agitation
True
T or F; Too hot or freezing temperature can cause rupture of RBCs
True
T or F; Serum/plasma does not need to be separated from cells before transport
Theoretically, False
You can also separate it in the lab
Documentation of proper sample identification from the time of collection to the receipt of laboratory results
Chain of custody
Ensures that any results reported relate beyond all reasonable doubt to a particular individual
Chain of Custody
Special care is needed when handling blood specimens to protect its condition and quality in terms of
- Body temperature
- Chilled specimen
- Light-sensitive specimen
Body temperature range in Celcius
36.4 °C-37.6 °C (37 average)
Room temperature range in Celcius
22 - 25 deg Celcius
Type of robot that delivers the sample to the laboratory
Robot Courier Autonomous Mobile Robot
T or F; some samples are transferred in body temperature because they precipitate in cold
True
What are the tests/samples maintained at 37 deg C?
Cold agglutinins
Cryoglobulin
Cryofibrinogen
What does cryo mean?
Cold
T or F; Chilling does not do anything with the metabolic process of the sample
False (it slows it down)
What is the classification of the ff samples/tests?
▪ Adrenocorticotropic hormone (ACTH)
▪ Acetone
▪ Ammonia
▪ Acid Phosphatase
▪ Catecholamines
▪ Lactic acid
▪ Parathyroid hormone
▪ pH/blood gases
Tests that require chilling
Temperature for chilling samples
4 °C (preferred temp.) or 2-8 °C
Ways/equipment to warm the samples
- Activated heel warmer
- Heat block
- Aluminum Double Head Heat Block
Chilling of uncentrifuged blood will elevate which electrolyte?
Potassium
Ways/equipment to chill the sample
- Blood specimen transporter
- Submerged in crushed ice and water slurry
In what direction is the microtainer and vacutainer label placed?
Left to right
What are the light-sensitive specimens?
- Bilirubin
- Folic acid
- Carotene
- Vitamins B2, B6, B12, and C
- Urine porphyrins
- Urine porphobilinogen
- Red Cell folate
- Serum folate
Up to what percent does bilirubin decrease after 1 hour of light exposure?
50 %
Ways to protect bilirubin from the sun
- Wrap in aluminum foil
- Use light-blocking amber tubes
amber ate ni sofia i was just a girl in the village doing alright
Where are collected specimens transported to?
Central processing triage or the sample reception area
T or F; unsuitable specimens are rejected then the phlebotomist cries
False (the phlebotomist obtains new specimen instead of crying)
Most frequent reason for rejection
(Chemistry Department)
▪ Hemolysis
▪ Insufficient amount of specimen QNS
Most frequent reason for rejection
(Hematology specimens)
▪ Clotting
▪ Underfilled tubes (for coagulation
studies)
Routine blood specimens should arrive at the
laboratory within ____ minutes of collection.
45
Specimens that require separation of the serum or plasma from the cells should be centrifuged within _____ minutes of arrival in the lab.
60 minutes / 1 hour
What is the maximum time limit for separating serum and plasma from the cells
2 hours from time of collection
Enumerate what would increase if serum tubes have not been spun within 2 hours or refrigeration of serum tubes before centrifugation
potassium, creatinine,
phosphorus, LDH, lactic acid, lipids and
total protein
Enumerate what would decrease if serum tubes have not been spun within 2 hours or refrigeration of serum tubes before centrifugation
glucose, ionized calcium,
chloride and carbon dioxide
Blood smears (EDTA) is prepared within how long?
1 hour
CBC (EDTA): recommended to be analyzed
within how many hours? In the room tempt, how many hours is it stable?
6 hours, 24 hours
CBC in micro-containers is analyzed w/in how many hours?
4 hours
Reticulocyte counts (EDTA) is stable up to ___
hours at RT; up to ___ hours if refrigerated
6 in room temperature; 72 if refrigerated
Glucose test (sodium fluoride tubes) is stable
up to ___ hours at RT; ___ hours if refrigerated
(2-8 C)
24 in room temperature; 48 if refrigerated
Prothrombin time (PT): unrefrigerated and uncentrifuged specimens up to ___ hours after
collection
24
Partial thromboplastin time (PTT): test specimens within __ hours of collection
4
Blood ammonia is separated within how many minutes?
15
Molecular test specimens with plasma, at 4 C, is stored for how many hours?
48
Three phases of specimen processing
Precentriguation
Centrifugation
Postcentrifugation
Refers to the specimen processing after specimen collection and before centrifugation
Precentrifugation
Refers to the specimen processing when the specimen is in the centrifuge
Centrifugation
Refers to the specimen processing after centrifugation and before removal of serum or
plasma
Postcentrifugation
Allow blood in nonadditive, clot activator, and gel-containing tubes used for serum tests (e.g., SSTs) to clot for the serum to separate from the cells
Precentrifugation
T or F; When clotting is not complete, latent fibrin formation may form a clot in the serum before centrifugation
False (after centrifugation)
Standard clotting time at room temperature
30 to 60 mins
Which specimens take longer to clot? Enumerate
◦ patients on anticoagulant medications, heparin or warfarin (e.g., Coumadin)
◦ from patients with high WBC counts
◦ chilled specimens
◦ from patients with bleeding disorders
What does “coagulopathies” mean?
Bleeding disorder
Tubes with clot activators clot within how many minutes?
30 mins
Tubes with thrombin clot in how many minutes?
5 mins
Complete clotting can be determined in what way/action?
Tilting and inverting the tube
T or F; rimming the tube with an applicator stick to release the clot from the walls of the tube is not a potential source of hemolysis and contamination
False (it is)
It is a process in which centrifugal force is used to separate solid matter from a liquid suspension
Centrfugation
machine that spins blood and other specimens at a high number of revolutions per minute (rpm) or centrifugal force
Centrifuge
Enumerate the three types of centrifuge
- Refrigerated
- Floor-top model
- Tabletop (benchtop) model
Unit for speed of rotation
revolution per minute (rpm)
Relative centrifugal force is expressed as?
gravity (g) or RCF
RCF depends on these two factors
speed of rotation (revolution per minute) and the radius of the rotor head
Most specimens centrifuged for 15 minutes are centrifuged at ______
750 g to 1000 g
Most specimens centrifuged for 10 minutes are centrifuged at ______
1000 g
T or F; removing the stopper of vacutainers during centrifugation will result in decreased pH
False (increased pH, less acidic because CO2 causes more alkalinity)
T or F; removing the stopper of vacutainers during centrifugation will result in dilution of analytes
False (concentration of analytes because solvent will evaporate if not sealed)
T or F; removing the stopper of vacutainers during centrifugation will result in aerosol formation
True
T or F; drop of sweat interferes with electrolyte results
True
What electrolytes in sweat may interfere with the electrolyte results during centrifugation?
Sodium and chloride
What should be the placement of specimen of equal-sized tubes in a balanced centrifugation?
Opposite
Centrifuging more than once may result in?
- Hemolysis
- Analyte detoriation
Which can alter results
T or F; Specimens that require chilling are processed in a normal centrifuge
False (in tempt-controlled refrigerated centrifuge)
T or F; It is important to schedule regular maintenance of centrifuge machine
True
What should be checked in routine maintenance of a centrifuge machine?
Balance
Braking mechanism
Centrifuge speed
Timer
What instrument is used to measure rpm?
Tachometer
STAT chem tests uses what color of tubes?
Green (Heparin reduces turn-around time)
Which color-coded tubes maintain specimen stability after centrifugation?
PSTs or other heparin-containing gel tubes
In postcentrifugation, what happens when the specimen is disturbed in tubes without separator gel?
Resuspension
What prevents glycolysis in postcentrifugation?
Physical barrier
T or F; Specimens in gel barrier tubes do not normally require manual separation
True
T or F; Serum or plasma is not required to separated from the cells as soon as possible
False
T or F; Stoppers are pulled l straight up to prevent release of aerosol: not “popped” off using a thumb roll technique
True
Serum on gel barriers can be stored up to ___ hours at ___°C
48 hours at 4 deg C
It is when the serum/plasma of the specimen is dark yellow instead of pale yellow
Icterus
It is when the serum/plasma of the specimen is cloudy, turbid
Lipemia
It is when the serum/plasma of the specimen is pink or red
Hemolysis
In hemolyzed specimen, which solutes are increased?
Potassium, ammonia, phosphate, and enzymes
a portion of a specimen used for testing
Aliquot
method of dividing or separating specimens into separate containers
Aliquoting
prepared when multiple tests are ordered on a single specimen
Aliquoting
What is used to aliquot and transfer specimen into tubes?
A disposable transfer pipet
Required Protective Equipment Worn when Processing Specimen is according to which law?
OSHA Act RA 11058