Your FREE ASCP PBT Flashcards 2026 – 200+ Cards

Tunica intima (inner endothelial lining), tunica media (middle muscle layer that controls diameter), tunica externa/adventitia (outer anchoring connective tissue).

The middle muscular/elastic layer that controls vessel diameter and blood flow (vasoconstriction/vasodilation).

AWAY from the heart, under high pressure, with thick muscular walls (no valves).

BACK to the heart, at low pressure, with one-way valves — the routine venipuncture target.

The pulmonary artery — it carries deoxygenated blood from the right ventricle to the lungs.

In the capillaries — vessels one cell thick where oxygen, nutrients, and waste diffuse between blood and tissue.

The left ventricle — it pumps oxygenated blood into the aorta against the highest (systemic) pressure.

Body → right atrium → right ventricle → lungs → left atrium → left ventricle → aorta → body.

The contraction phase of the heart when blood is pumped out of the ventricles.

The relaxation phase of the heart when the chambers fill with blood.

The coronary arteries (which branch off the aorta).

Red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes).

Carry oxygen (via hemoglobin) from the lungs to the tissues.

Defend the body against infection (immune response).

Initiate clotting (hemostasis) by forming a platelet plug at an injury.

About 55% plasma (liquid) and 45% formed elements (cells).

Plasma (from an anticoagulated tube) still contains fibrinogen; serum (from a clotted tube) has NO fibrinogen or clotting factors.

A tube allowed to clot — red (no additive/clot activator) or gold SST (clot activator + gel).

Anticoagulated tubes — e.g. green (heparin), lavender (EDTA), light blue (citrate).

The median cubital vein in the antecubital fossa — large, well-anchored, away from artery and nerve.

The cephalic vein (lateral, thumb side of the forearm).

The basilic vein (medial) — used last because it lies near the brachial artery and median nerve.

The inner bend (anterior surface) of the elbow — the primary region for routine venipuncture.

Palpation (feel) — a vein you can feel bounce is patent; do not rely on sight alone.

The body's process of stopping bleeding: vascular spasm, platelet plug, and the coagulation cascade forming fibrin.

It is converted to fibrin, the mesh that stabilizes a clot; it is present in plasma but absent in serum.

Type O is the universal red-cell donor; type AB is the universal recipient.

The D antigen on red blood cells — present = Rh-positive, absent = Rh-negative.

The study of blood and blood-forming tissues, including cell counts like the CBC.

The hollow interior channel of a blood vessel through which blood flows.

Bright-red, pulsing, rapidly filling blood — remove the needle and apply firm pressure.

The smallest veins (venules) and smallest arteries (arterioles) that connect to capillary beds.

Between chambers and at the great vessels; they keep blood flowing one way and prevent backflow.

Erythrocyte = red blood cell (oxygen carrier); leukocyte = white blood cell (immune defense).

Blood culture → light blue (citrate) → red/gold serum (SST) → green (heparin) → lavender (EDTA) → gray (fluoride/oxalate).

To keep the specimen sterile and avoid false-positive contamination from skin flora.

EDTA carryover into a later tube falsely raises potassium and lowers calcium, skewing chemistry results.

Sodium citrate; coagulation tests (PT/INR, aPTT, D-dimer).

None or clot activator (± gel); serum chemistry and serology.

Heparin (lithium or sodium); plasma chemistry and stat electrolytes.

EDTA; CBC and HbA1c (pink top = blood bank).

Sodium fluoride + potassium oxalate; glucose and lactate.

SPS (blood cultures) or ACD (blood bank / DNA / paternity).

It REVERSIBLY binds (chelates) calcium needed for clotting.

It IRREVERSIBLY binds (chelates) calcium, preserving cell shape for the CBC.

It potentiates antithrombin, inhibiting thrombin and clot formation.

It is antiglycolytic — it stops blood cells from consuming glucose.

9:1 blood-to-additive; must be filled to the line.

Excess citrate over-binds the lab's calcium reagent, falsely prolonging PT/aPTT (raising INR) — the lab rejects it.

21–23 gauge (21 G is the standard).

23–25 gauge — for small, fragile, or hand veins.

A HIGHER number = a SMALLER bore (counterintuitive).

Up (bevel-up) on insertion.

About 15–30° to the arm.

No more than 1 minute.

Hemoconcentration — falsely elevated proteins, potassium, and cell counts.

3–4 inches above the intended puncture site.

At least two — typically full name and date of birth.

The room or bed number (patients move).

At the bedside, in the patient's presence, immediately after the draw.

70% isopropyl alcohol — applied in a circular motion and allowed to air-dry.

Chlorhexidine (or povidone-iodine), not plain alcohol, because sterility is critical.

A non-alcohol antiseptic (e.g. povidone-iodine) so the prep can't affect the result.

Mastectomy side, an arm with an IV, hematomas, scarred/burned/edematous skin, and AV fistulas.

Lymphedema and infection risk — draw from the opposite arm.

IV fluid contaminates and dilutes the sample — use the other arm or draw below the IV.

Blood gas → EDTA (lavender) FIRST → other additives → serum LAST.

The puncture activates platelets immediately, so the cell count must be collected before clumping skews it.

The medial or lateral plantar (side) surface of the heel — never the center or arch (to avoid bone).

Warming increases blood flow to the site, improving collection.

Wipe it away — it contains tissue fluid that can skew results.

It hemolyzes the sample and adds tissue fluid — apply only gentle, intermittent pressure.

The evacuated tube system (ETS) — holder, double-ended needle, and self-filling vacuum tubes.

For fragile or difficult veins where vacuum pressure might collapse the vein.

Draw a discard tube first to fill the tubing's dead space so the citrate ratio is correct.

STAT = immediate; routine = standard turnaround; timed = drawn at a specific time (e.g. drug peak/trough, GTT).

Gently invert (don't shake) — typically 8–10 times for most additive tubes, 3–4 for citrate.

Fasting baseline draw, a measured glucose load, then timed draws (e.g. 1- and 2-hour).

The exact time of collection relative to the dose (peak vs trough).

Just BEFORE the next dose (lowest concentration).

After the dose has distributed (highest concentration), per the drug's timing.

Have them lie down or sit in a reclining chair for the draw.

Drawn after no food or caloric drinks (water allowed), typically 8–12 hours, for tests like fasting glucose.

Current guidance makes non-fasting the routine default; a fast is reserved for very high triglycerides or a lipid workup.

Early morning, rested, fasting — the condition that gives the most reproducible results.

Cortisol and serum iron (both peak in the morning) — draw at the time the test specifies.

Informed (understands procedure), expressed (explicit verbal/written), implied (inferred — e.g. arm extended).

Requires a parent's or legal guardian's permission.

Do not force it — document the refusal and notify the nurse or provider.

Pull the skin taut below the site to stabilize the vein before insertion.

Immediately when the needle leaves the arm — before disposal.

High needlestick risk; OSHA prohibits it — drop sharps directly into the container.

Release the tourniquet before withdrawing the needle.

Complete blood count (CBC) and HbA1c.

Coagulation studies — PT/INR and aPTT.

Common arrangements of the median cubital, cephalic, and basilic veins in the antecubital fossa.

Release the tourniquet, wait, then reapply — don't leave it on.

About two attempts, then ask another phlebotomist or escalate — avoid blind probing.

Wet alcohol can cause a stinging sensation, hemolysis, and a false result; let it dry.

A butterfly — flexible tubing with a small-gauge needle for fragile/hand veins.

It sits near the brachial artery and median nerve — higher risk of arterial puncture or nerve injury.

Seated with the arm supported and extended downward; reclining if syncope-prone.

Often two sets from two separate sites to distinguish true infection from contamination.

Too little blood is the most common cause of a false-negative culture.

'Studies Begin Right Going Lab Gray' — Sterile, Blue, Red, Green, Lavender, Gray.

Green (heparin) tube for rapid plasma chemistry.

EDTA tube designated for blood bank (type and screen / crossmatch).

Tube expiration dates, the right additives, correct needle, and that supplies are sterile/intact.

Rejected — the 9:1 ratio is off, invalidating PT/aPTT.

Misidentification is a leading cause of transfusion errors and one of the most serious pre-analytical errors.

Which tubes to collect, required volume, special handling, and the timing of the draw.

Stop and resolve it before drawing — never assume.

Skin puncture yields capillary (mixed arterial-venous + tissue fluid) blood; venipuncture yields venous blood.

Small sample volume needed (infants) or poor venous access.

The heel bone is close to the surface only in infants; older children/adults use a fingerstick.

The side of the middle or ring fingertip, slightly off-center, perpendicular to the fingerprint lines.

Failure to mix (invert) the tube promptly after collection.

Shaking hemolyzes the sample; gentle inversion mixes additive without rupturing cells.

Hemolysis, clotted tube, QNS/wrong fill, mislabeled/unlabeled, wrong tube/additive, and improper handling.

Rupture of red blood cells releasing their contents — makes serum pink/red and falsely raises K, LDH, AST.

Needle too small, forceful draw, shaking tubes, prolonged tourniquet, drawing from a hematoma.

Never relabel — reject and recollect using two identifiers.

Quantity Not Sufficient — too little specimen (or wrong ratio) to run the test.

Logging a received specimen into the lab system and assigning a unique tracking number.

Patient name, ID, date of birth, date and time of collection, and the collector's initials.

About 30 minutes at room temperature for full clotting.

About 60 minutes at room temperature.

Incomplete clotting leaves fibrin strands that interfere with the analyzer.

Within about 2 hours of collection.

Cells alter glucose, potassium, and other analytes over time.

No — re-spinning can release analytes from cells trapped above the gel.

Always place tubes of equal weight opposite each other; an unbalanced centrifuge is unsafe.

A measured portion poured off from the primary specimen for separate testing, labeled to match it.

Ammonia, lactate, and arterial blood gases.

Bilirubin (use an amber tube or wrap in foil).

Cold agglutinins and cryoglobulins (they precipitate when cooled).

It can hemolyze fragile specimens — some samples must be hand-carried.

A result so abnormal it requires immediate provider notification.

Reject it; do not test or relabel — the patient must be recollected.

To verify the specimen meets the test's required transport/storage conditions.

Pre-analytical (collection/handling) — the phlebotomist's domain — outnumber analytical and post-analytical errors.

Pre-analytical, analytical, and post-analytical.

Cloudy, fatty serum (high triglycerides) that can interfere with some assays.

Yellow serum discoloration from high bilirubin.

Follow the test's requirement — refrigerate, freeze, keep at room temp, chill, or keep warm as specified.

Inadequate mixing causes microclots that invalidate the result (especially the CBC).

An underfilled tube (wrong 9:1 ratio) or a hemolyzed/contaminated sample.

Keep cold (refrigerated/on ice) during the collection and transport.

Depends on the analyte's stability in the already-collected specimen — some are too degraded to add on.

To prevent mixing up tubes from different patients — the most dangerous labeling error.

Cells (bottom) from serum or plasma (top); a gel barrier forms in an SST.

Glycolysis lowers the glucose result over time (unless a fluoride tube was used).

Avoid hemolysis and prolonged cell contact — both falsely raise potassium.

Potassium is concentrated inside red cells; rupture releases it into the serum/plasma.

Collected as dried blood spots on filter paper; air-dry, don't stack or contaminate, and mail promptly.

Whether the sample is suitable for testing — correct type, volume, additive, and handling, free of hemolysis/clots.

Note it, and recollect if the test is affected — many analytes can't be reported from a hemolyzed sample.

It is a quality-improvement metric; delays can affect patient care, especially for STAT tests.

Laboratory testing performed at or near the patient (bedside, clinic) rather than in a central lab.

The FDA cleared it as simple and low-risk for error, so it can run outside a high-complexity lab.

Glucose meters, hemoglobin/hematocrit, PT/INR, urine dipstick, and rapid strep/flu/pregnancy/COVID kits.

Run quality control and follow the manufacturer's instructions exactly.

Internal = built-in electronic/onboard check; external = liquid control samples with known values.

STOP — do not report patient results; troubleshoot, check reagent/storage, and rerun QC first.

Expired/improperly stored strip, insufficient sample, or a malfunctioning/cold device.

Strips/cartridges are temperature- and humidity-sensitive; improper storage invalidates results.

A problem with the sample or device — repeat with a fresh strip/sample per the instructions; don't force a result.

Setting the device against a known standard so its readings are accurate; done per the manufacturer's schedule.

Warfarin (anticoagulant) therapy.

A reagent dipstick read for glucose, protein, pH, blood, leukocytes, ketones, etc.

A throat swab of the tonsils and posterior pharynx.

Urine (ideally first-morning, most concentrated) — or serum for a quantitative test.

Regulatory requirement (CLIA) and proof the result is reliable for patient care.

Trained, competency-assessed operators following the manufacturer's instructions.

That the device and reagent are working before patient samples are run.

Hemoglobin = oxygen-carrying protein concentration; hematocrit = the % of blood volume that is red cells.

Inaccurate (often falsely low/high) results — always check the expiration date.

Confirm QC has passed and the device is calibrated and in date.

Periodic verification that an operator can correctly perform the test and QC.

Faster turnaround at the bedside for time-critical results (e.g. glucose, INR).

An error or a falsely low result — apply enough sample per the device.

When a new reagent lot is opened, run QC to confirm it performs like the previous lot.

The QC log / reagent log (lot number, expiration, and QC results).

Any voided sample, collected at any time — used for routine urinalysis.

Cleanse first, begin the stream, then catch the middle — minimizes contamination for a culture.

Discard the first void (note the time), collect every void for 24 hours kept cold, end with a final void.

To start the timed clock with an empty bladder so the result reflects exactly 24 hours.

Missing or discarding any void during the collection window.

It is the most concentrated — best for pregnancy and microalbumin testing.

Early morning, as a deep cough (not saliva).

May require avoiding red meat and certain medications for a few days beforehand.

Cystic fibrosis (collected by iontophoresis/pilocarpine stimulation).

Swab the tonsils and posterior pharynx, avoiding the tongue and cheeks.

Recovering respiratory viruses/bacteria (e.g. flu, COVID, pertussis) — insert along the nasal floor.

Urea breath test for H. pylori; hydrogen breath test for lactose intolerance.

To keep the organism viable until it reaches the lab for culture.

A large container that may contain an acid or other preservative — verify the test requirement first.

CSF for meningitis, urine for UTI, sputum for pneumonia — the right specimen for the right test.

To confirm a fresh, unadulterated (not substituted) specimen right after collection.

Documented, unbroken, tamper-evident handling of a specimen from collection to testing, with signed transfers.

For forensic/legal specimens — most often urine drug screens and blood-alcohol tests.

Wipe front-to-back/clean the area, void a little, then collect midstream into the sterile cup.

A physician (lumbar puncture); the phlebotomist/lab processes and routes the tubes in order.

Detect enteric pathogens (bacteria/parasites) causing GI infection.

If it is mostly saliva rather than lower-respiratory secretions.

Collecting cheek cells for DNA/genetic testing.

Collected per strict instructions and delivered to the lab within a short, specified time, kept near body temperature.

For any culture (urine, sputum, swab) to prevent contamination from skewing the result.

QC = day-to-day checks that a test runs correctly; QA = ongoing monitoring of the whole process (all three phases).

A QC comparison of a patient's current result with a recent prior one; a big unexpected change flags a possible error.

External unknown samples sent to the lab to verify its results agree with peer laboratories.

Periodic verification that staff can correctly and safely perform their tasks.

Pre-analytical (patient prep, collection, handling, labeling).

To document and track errors and near-misses for quality improvement.

All clinical laboratory testing on humans in the U.S. (administered by CMS).

Laboratory accreditation and inspection.

Develops consensus standards (e.g. the order of draw, specimen labeling and handling).

Workplace safety — including the Bloodborne Pathogens Standard.

Regulate shipping/transport of infectious substances (Category A and B).

29 CFR 1910.1030.

Provide free PPE, safety-engineered sharps, sharps containers, a free hepatitis B vaccine, and an exposure-control plan.

Never recap, bend, or break by hand — drop directly into the sharps container.

Closable, puncture-resistant, leak-proof, biohazard-labeled, at the point of use.

Treat every patient's blood and body fluids as potentially infectious — hand hygiene, gloves, PPE.

Hand hygiene before and after every patient.

Gown → mask → eye protection → gloves.

Gloves → eye protection → gown → mask, then hand hygiene.

Wash the site with soap and water, report immediately, and follow the exposure-control plan.

Free, within 10 working days of assignment to at-risk duties.

Federal law protecting a patient's protected health information (PHI).

Access/share only on a need-to-know basis; keep requisitions and screens secure; never discuss patients publicly.

Collect, handle, and process specimens — not diagnose or interpret results.

Negligence = failure to exercise reasonable care; malpractice = negligence by a professional in their duties.

A document describing a chemical's hazards, handling, storage, and first aid — kept accessible to staff.

Protect yourself/others and follow the SDS and facility spill procedure; contain and report it.

Reducing waste and non-value steps to improve efficiency and turnaround.

A data-driven quality method aimed at reducing errors/defects in processes.

The reagent/QC log (lot number, expiration, QC results).

Immediate notification of the provider and documentation of the read-back.

The time from order/collection to result reporting — a key quality metric.

Contact, droplet, airborne, vector, and vehicle (blood/fluids) — standard precautions reduce them.

In addition to standard precautions for patients with specific contagious infections.

Category A = capable of causing permanent disability/death (stricter packaging); Category B = most diagnostic specimens.

Rescue, Alarm, Confine, Extinguish/Evacuate — the response to a lab fire.

The patient agrees to the procedure after understanding its purpose and risks.

To kill pathogens between patients/spills — use an approved disinfectant per facility policy.

A notice that a test may not be covered, so the patient may be responsible for payment.

HIPAA mandates it; breaches can result in penalties and loss of trust.