Deck 5 – Additives, Tests & Lab Basics
Understand additives, specimen types, and lab essentials that drive correct tube selection.
NHA CPT EXAM
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Additive
A substance put in a blood collection tube (anticoagulant or clot activator) to change how the specimen behaves or is processed.
Anticoagulant
A chemical that prevents blood from clotting by interfering with the clotting process (e.g., EDTA, heparin, sodium citrate).
Blood Culture
A test that checks for microorganisms in the bloodstream, collected in special culture bottles or yellow SPS tubes.
Butterfly (Winged Infusion Set)
A small-gauge needle with flexible tubing and plastic wings used for small, fragile, or difficult veins.
Capillary Puncture
Collecting blood from small vessels near the skin surface (finger or heel) using a lancet.
Centrifuge
A machine that spins blood samples to separate components by density (serum or plasma from cells).
CLIA (Clinical Laboratory Improvement Amendments
U.S. regulations that set quality standards for laboratory testing, including some POCT.
Coagulation Tests
Tests that evaluate how well blood clots (e.g., PT, INR, aPTT).
EDTA (Ethylenediaminetetraacetic Acid)
An anticoagulant that binds calcium and preserves cell morphology; found in lavender and pink tubes.
Fasting Sample
A specimen collected after a set period without food (and sometimes drinks/medications).
Glycolysis
The breakdown of glucose by cells in a blood sample, which can falsely lower measured glucose.
Gray Tube
A tube containing sodium fluoride and an anticoagulant, used for glucose and some lactic acid tests.
Green Tube
A tube containing heparin anticoagulant, used to produce plasma for certain chemistry tests.
Hemolysis
Rupture of red blood cells releasing hemoglobin into serum or plasma, making many tests inaccurate.
Heelstick
A capillary puncture on the lateral or medial plantar surface of an infant’s heel.
Lavender Tube
A blood collection tube containing EDTA anticoagulant, commonly used for CBC, ESR, and other hematology tests.
Light Blue Tube
A tube containing sodium citrate anticoagulant, used mainly for coagulation tests such as PT, INR, and aPTT.
Order of Draw
The specific sequence in which tubes must be filled during venipuncture to avoid additive carryover and inaccurate results.
Phlebotomy
The practice of drawing blood from a vein, capillary, or artery for laboratory testing or other purposes.
Plasma
The liquid portion of blood in a sample collected with anticoagulant; it still contains clotting factors.
Point-of-Care Testing (POCT)
Simple tests performed near or at the patient’s location with quick results (e.g., bedside glucose, rapid strep).
Quality Assurance (QA)
The overall program of policies, procedures, and audits that ensures all steps in patient testing are done correctly and safely.
Quality Control (QC)
The daily checks (controls, calibration, logs) that make sure a specific test or device is working properly.
Random Urine Sample
A urine specimen collected at any time of day without special preparation, often used for routine screening.
Serum
The liquid portion of blood obtained after it has clotted and been centrifuged; it does not contain clotting factors.
Specimen Rejection
The process of refusing a sample for testing due to problems like mislabeling, hemolysis, wrong tube, low volume, or contamination.
Stat Test
A test that must be performed and resulted as quickly as possible due to urgent clinical need.
Venipuncture
The process of puncturing a vein with a needle to obtain a blood sample for laboratory testing.
Aliquot
A small portion of a specimen transferred into another container for testing without contaminating the original sample.
Analytical phase
The phase of testing when the lab actually runs the test on the specimen.
Bilirubin
A yellow pigment from red blood cell breakdown; some tests for it require protection from light.
Calcium oxalate
A preservative and anticoagulant used in some lab settings to prevent clotting.
Catheterized urine specimen
Urine collected through a catheter placed into the bladder by trained personnel.
Chain of custody
Documentation that tracks a specimen from collection to testing for legal/forensic purposes.
Chlorhexidine
A strong antiseptic often used for blood cultures or central line site cleaning.
CLSI (Clinical and Laboratory Standards Institute)
Organization that publishes many phlebotomy and laboratory practice guidelines.
Critical value
A lab result so abnormal it may be life-threatening and must be reported immediately.
Crossmatch
Blood bank test that checks compatibility between donor and recipient blood before transfusion.
Culture and sensitivity (C&S)
A test that grows microorganisms and checks which antibiotics can kill them.
Pre-analytical phase
All the steps that happen before the test is run: patient prep, collection, labeling, handling, and transport.
Differential count
Part of a CBC that shows the percentage of each type of white blood cell.
Electrolytes
Charged particles in blood like sodium, potassium, and chloride measured in chemistry tests.
Glucose tolerance test (GTT)
A series of timed blood tests after the patient drinks a measured glucose solution.
Heel warmer
A device used to warm an infant’s heel before a heelstick to increase blood flow.
Hyperglycemia
Higher-than-normal blood glucose levels.
Hypoglycemia
Lower-than-normal blood glucose levels that can cause confusion, shakiness, or fainting.
Immunology
Lab department that tests for antibodies and immune responses.
Iodine
A strong antiseptic used for some skin preparations and blood culture collections.
Lipemic specimen
A blood sample that looks milky or cloudy because of high fat content.
Microcollection container
Small plastic tube used to collect capillary blood in fingersticks or heelsticks.
Outpatient
A patient who receives care or testing but does not stay overnight.
Preservative
A chemical in a container that slows down or prevents changes in the specimen.
Quantitative test
A test that gives a numeric value for how much of a substance is present.
Qualitative test
A test that reports whether a substance is present or absent, not how much is there.
Quality indicator
A measurable item used to monitor how well a process is working, such as the rate of specimen rejection.
Random glucose
A blood glucose measurement taken at any time, without special preparation.
Reference range
The set of values considered normal for a healthy person for a specific lab test.
Requisition form
The written or electronic order that tells you which tests to collect and from which patient.
Serology
The lab section that tests serum for antibodies and certain infections.
Sharps
Objects that can puncture the skin, such as needles or lancets, that require special disposal.
Sodium fluoride
An additive that slows glycolysis to help preserve glucose levels in a blood sample.
Specimen integrity
The condition of a sample being suitable and reliable for testing.
Stool specimen
A sample of feces collected to test for infection, blood, parasites, or other conditions.
Timed specimen
A specimen collected at a specific time or at set intervals (for example, drug levels or GTT samples).
Turbid specimen
A sample that looks cloudy or opaque, possibly due to cells, fat, or other particles.
Urinalysis
A series of tests performed on urine to evaluate kidney function and detect disease.
Waived test
A simple lab test with low risk of error that is cleared for use in many non-lab settings.
Warmed specimen
A sample that must be kept at body or near-body temperature from collection to testing.
CBC
Stands for “Complete Blood Count,” a common hematology test panel.
PT
Stands for “Prothrombin Time,” a coagulation test.
aPTT or PTT
Stands for “(Activated) Partial Thromboplastin Time,” another coagulation test.
BMP
Stands for “Basic Metabolic Panel,” a group of common chemistry tests.
CMP
Stands for “Comprehensive Metabolic Panel,” a larger chemistry panel.
CO2
Abbreviation for carbon dioxide/bicarbonate on chemistry panels.
BUN
Stands for “Blood Urea Nitrogen,” a test of kidney function.
ESR
Stands for “Erythrocyte Sedimentation Rate,” a hematology test for inflammation.
CRP
Stands for “C-reactive protein,” a blood test that rises with inflammation.
ABG
Stands for “Arterial Blood Gas,” a test of oxygen, carbon dioxide, and pH in arterial blood.
LFTs
Stands for “Liver Function Tests,” a group of tests like AST, ALT, ALP, and bilirubin.
HbA1c
Abbreviation for “Hemoglobin A1c,” a test showing average blood glucose over about 3 months.
ECG or EKG
Stands for “Electrocardiogram,” a test of electrical activity of the heart.
Arterial blood
Blood taken from an artery, typically for blood gas (ABG) testing.
Capillary order of draw
The recommended sequence for microcollection: typically blood gases → EDTA → other additive tubes → serum.
Diurnal variation
Normal daily (24-hour) changes in lab values depending on the time of day.
Postprandial specimen
A specimen collected after the patient has eaten a meal (for example, 2 hours after).
24-hour urine collection
A urine test where all urine over 24 hours is collected in a large container.
Occult blood test
A test that checks for hidden (occult) blood in stool samples.
Neonatal screening (PKU card)
A heelstick blood collection on special filter paper cards to screen newborns for certain disorders.
Glucose challenge test
A screening test where the patient drinks a measured glucose load and a single timed blood sample is taken.
Short draw
A tube that is not filled to the required volume for that test.
Clotted specimen
A sample that has formed a clot in a tube that was supposed to remain anticoagulated.
Icteric specimen
A blood sample with a deep yellow or greenish color due to very high bilirubin.
Lipemic specimen (advanced)
A blood sample that is extremely milky or cloudy from high fat content after a recent high-fat meal.
QNS (Quantity Not Sufficient)
A specimen where the volume collected is not enough to perform the ordered test(s).
Specimen mislabeling
Labeling a specimen with the wrong patient information or missing required data.
Sputum specimen
A thick mucus sample coughed up from the lungs, used to test for infection (for example, TB).
Throat swab
A swab taken from the back of the throat and tonsil area to test for infections like strep throat.
Nasopharyngeal swab
A swab collected from deep inside the nasal passage to test for respiratory viruses or other pathogens.
Wound culture swab
A swab taken from an open wound or drainage to identify infecting organisms.
Semen specimen
A sample of semen collected to evaluate fertility or confirm vasectomy success.
Amniotic fluid
Fluid surrounding a fetus in the uterus, collected to test for genetic conditions or fetal lung maturity.
Gastric fluid specimen
A sample of stomach contents collected to evaluate acidity, bleeding, or infection.
Sweat chloride test
A test where sweat is collected from the skin to measure chloride levels, often used to diagnose cystic fibrosis.
Fine-needle aspiration specimen
Cells collected with a very thin needle from tissue or a mass to examine for cancer or other disease.
Slide labeling
Labeling blood smear slides with at least two patient identifiers and collection date/time.
Specimen transport bag
A leak-resistant plastic bag used to transport specimens, often with a separate pocket for paperwork.
Pneumatic tube system
A system of pressurized tubes used to send specimens quickly through the hospital.
Maximum heel puncture depth
The depth for infant heelsticks is usually limited to about 2.0 mm to avoid injuring bone.
Oral glucose tolerance test (OGTT)
A test where the patient fasts, drinks a measured glucose solution, and has multiple timed blood samples taken.
Lipid panel fasting requirement
Many lipid panels require 8–12 hours of fasting before the blood draw for accurate triglyceride and LDL measurements.
Therapeutic drug monitoring (TDM)
Testing drug levels in the blood at specific times (peak and trough) to guide dosing.
Turnaround time (TAT)
The total time from when a test is ordered or specimen is collected until the result is reported.
Accession number
A unique number or code assigned to each specimen when it is received or logged in the lab.
Hematology department
The lab section that performs tests on blood cells, such as CBC, ESR, and differentials.
Chemistry department
The lab section that performs tests on chemicals in blood and body fluids, such as glucose, electrolytes, and enzymes.
Microbiology department
The lab section that grows and identifies microorganisms from specimens like blood, urine, stool, and sputum.
Coagulation department
The lab area that tests how well blood clots, including PT, INR, and aPTT.
Pathology department
The lab section that examines tissue and cells (biopsies, surgical specimens, cytology) to diagnose disease.
Reference laboratory
An outside laboratory that performs specialized or less common tests sent out from the main facility.
Point-of-care coordinator
The person who oversees POCT devices, training, and quality control in a facility.
Lab information system (LIS)
The computer system used to order tests, track specimens, and report lab results.
Courier (specimen transport)
A person or service that transports specimens between collection sites and the laboratory.
Standing order
A lab order that remains in effect and is repeated at set intervals until it is changed or canceled.
One-time order
A lab order for a single, specific specimen collection at a given time.
Add-on order
An additional test requested on a specimen that has already been collected, if enough volume remains.
Test cancellation
The process of stopping a lab order so the test is not performed.
Proficiency testing (PT)
External testing where a lab analyzes unknown samples from an outside agency to check accuracy.
Quality control range
The acceptable high and low values for a control material used to check test performance.
Calibration
The process of adjusting an instrument or test system so results are accurate compared with known standards.
Pretest patient instructions
Instructions given to a patient before testing (for example, fasting, medication holds, timing).
Post-test patient instructions
Information given to the patient after specimen collection (for example, keep bandage on, avoid heavy lifting).
CAP (College of American Pathologists)
An organization that accredits many clinical laboratories and sets quality standards.
CLIA-waived test
A simple, low-risk test approved for many non-lab settings under CLIA regulations.
Moderate complexity test
A lab test that requires more training and oversight than a waived test.
High complexity test
A lab test that requires advanced training, specialized equipment, and strict oversight.
Critical value read-back
The practice of repeating a critical test result back to the person who reported it to confirm accuracy.
Specimen storage temperature
The required temperature range (room temperature, refrigerated, or frozen) for holding specimens before testing.
Equipment maintenance log
A record of routine maintenance, checks, and repairs performed on lab instruments.