NHA Phlebotomy Technician (CPT) — All Questions

An 82-year-old patient has thin, papery skin and prominent but fragile veins. Which set of adjustments is appropriate?

• a.Apply the tourniquet more tightly than usual so the fragile vein is held firmly in position
• b.Use the largest tube available so the draw finishes before the vein has time to collapse
• c.Slap the skin over the vein to raise it, then insert quickly at a steep angle
• d.Use a winged set and small tubes, anchor gently, and hold pressure for longer afterwards✓

Fragile veins tolerate less vacuum and fragile skin tolerates less traction, so a winged set with small volume tubes, gentle anchoring and unhurried entry protect both. Pressure is held longer because older patients bleed longer, particularly on aspirin or an anticoagulant. A tighter tourniquet, a larger tube and slapping the skin all increase the risk of hematoma and skin tearing.

How should a phlebotomist secure the puncture site on an older patient whose skin tears easily?

• a.Hold gauze with pressure, then wrap it with a self-adherent bandage instead of adhesive tape✓
• b.Apply a strong adhesive tape and warn the patient to pull it off quickly in a single movement
• c.Skip any covering, since older skin heals fastest when the site is left completely open
• d.Use two adhesive bandages crossed over one another so the gauze cannot slip out of place

Self-adherent wrap sticks to itself rather than to skin, so it holds gauze in place without stripping tissue when it comes off. Adhesive tape on paper-thin skin can tear it and open a wound that heals slowly. Leaving the site uncovered risks bleeding restarting, and doubling adhesives multiplies the very problem being avoided.

A phlebotomist is drawing blood from a patient with advanced dementia who does not respond to questions. How should identification be handled?

• a.Accept the room number and the name written on the door as the two required identifiers
• b.Verify the wristband against the requisition and have a caregiver or nurse confirm the identity✓
• c.Ask the patient to state her own name and accept whatever answer she gives without any further checking
• d.Draw the specimen first and confirm the identity with the nurse before the label is applied

A patient who cannot reliably state her own name is identified from the wristband checked against the requisition, with a nurse, caregiver or family member confirming. Room numbers and door signs are not patient identifiers and change constantly. Accepting an unreliable verbal answer, or labelling after the fact, are the two routes to a wrong-patient result and a wrong transfusion.

Which microhematocrit tube should be used to fill directly from a capillary puncture with no anticoagulant tube in between?

• a.The tube with a blue band, which contains no additive at all
• b.Either tube, because the sample spins down to the same packed cell volume in both cases
• c.The tube with a red band, which is coated on the inside with heparin✓
• d.Neither, because a hematocrit can only be run from a venous lavender tube

Blood taken straight from a skin puncture has nothing to stop it clotting, so the heparinised tube, marked with a red band, is the correct choice. The blue banded plain tube is used when the blood has already been anticoagulated, typically from a lavender EDTA tube. A clotted specimen gives a meaningless packed cell volume, and hematocrit is routinely performed on capillary blood.

A parent asks to hold her two-year-old during a venipuncture. What is the usual practice?

• a.Parents are excluded from the room so that their anxiety cannot transfer to the child
• b.The parent may stay only if she agrees to hold the arm still while the needle is inserted
• c.The child must be swaddled alone on a table, because any holding contaminates the site
• d.A supportive hold with the parent present is encouraged where facility policy allows it✓

Comfort positioning, with the child upright on the parent's lap and the arm supported, reduces distress and struggling and is widely encouraged where policy permits. Excluding a parent is not the norm, and asking a parent to restrain a child places them in the role the child will remember. Being held does not contaminate a site that is prepared and kept clean.

How long should a heel warming device be applied before a newborn capillary collection, and at what temperature?

• a.Three to five minutes at a temperature no higher than about 42 degrees Celsius✓
• b.Fifteen to twenty minutes at whatever temperature the nursery warmer happens to be set to
• c.Thirty seconds at 50 degrees Celsius, which opens the capillaries fastest of all the options
• d.Warming is not used on newborns because their circulation is already at its maximum

Three to five minutes of gentle warming at a ceiling of about 42 degrees Celsius increases blood flow to the heel several fold and makes a single puncture sufficient. Hotter packs scald infant skin, which is thinner than an adult's. A quarter of an hour is unnecessary and leaves the infant handled longer than needed, and warming is a standard part of neonatal capillary collection.

Which specimen should not be collected by skin puncture?

• a.A hemoglobin and hematocrit on a patient whose veins are exhausted from repeated draws
• b.A set of blood cultures on a patient with a suspected bloodstream infection✓
• c.A point of care glucose on a patient in an outpatient diabetes clinic
• d.A newborn screening card on a two-day-old infant in the nursery

Blood cultures need a volume that a skin puncture cannot supply, and the puncture site cannot be kept sterile through a capillary collection, so contamination and false negatives follow. Point of care glucose, newborn screening and small volume hematology are all standard capillary work. Tests requiring plasma or serum in quantity, and coagulation studies, are also unsuitable.

A capillary glucose is collected from a patient's fingertip immediately after the patient has eaten an orange without washing their hands. What is the risk?

• a.Citric acid on the skin destroys the glucose in the sample and the meter will read far too low
• b.There is no risk, because the meter measures only what it draws in
• c.Sugar residue on the finger can be picked up in the drop and give a falsely high glucose✓
• d.The fruit acid corrodes the test strip so the meter displays an error rather than a number

Contamination from food, juice, lotion or an alcohol-based hand product on the fingertip is a documented cause of falsely high point of care glucose readings, and a spuriously high result can prompt an insulin dose the patient does not need. The site is washed with soap and water and dried before the puncture. Meters measure glucose in whole blood, not only inside cells.

A phlebotomist runs the low and high control solutions on a point of care glucose meter and the high control falls outside its range. What is the correct action?

• a.Do not report patient results from that meter; troubleshoot and repeat before any patient is tested✓
• b.Report the patient results but add a comment noting that the high control was out of range that morning
• c.Run only the low control from then on, since it was the one that gave an acceptable result
• d.Test the patient anyway and repeat the control afterwards to see whether it corrects itself

A failed control means the instrument has not demonstrated that it can measure accurately, so patient testing stops until the cause is found, whether it is an expired strip lot, a storage problem, a coding error or the meter itself. Reporting with a comment, dropping a control level or testing first and checking later all put a patient result of unknown accuracy into the record.

A patient at an outpatient clinic needs a hemoglobin A1c and has excellent antecubital veins. Why is a venous draw usually preferred over a capillary one here?

• a.Capillary blood cannot be used for a hemoglobin A1c under any circumstances at all
• b.A venous specimen gives adequate volume and avoids the tissue fluid a skin puncture adds✓
• c.Capillary punctures are more painful than venipuncture, so patients refuse them more often
• d.A capillary sample would clot immediately because no microtube contains a suitable additive

Where a good vein is available, a venous EDTA tube supplies ample well mixed whole blood without the interstitial fluid dilution and hemolysis risk that come with a skin puncture. Capillary A1c testing does exist on waived devices and is used where venous access is difficult, so it is not forbidden. Microtubes with EDTA are readily available, and pain is a poor basis for the choice.

A lancet has been used for a fingerstick and the collection is complete. How is it discarded?

• a.Rinse it under running water and place it in the regular waste after the blood is removed
• b.Retract the blade, then set it on the tray until the whole round of patients is finished
• c.Place it in a red biohazard bag along with the used gauze and the wrappers
• d.Drop it into a sharps container at the point of use, without recapping or resheathing✓

Any device that has punctured skin goes straight into a puncture resistant sharps container at the place it was used, not into a bag, a tray or the ordinary trash. A biohazard bag holds soft regulated waste and offers no protection against a blade. Rinsing a contaminated sharp creates a splash hazard, and carrying used sharps around is how injuries to housekeeping staff happen.

Which single factor has the greatest influence on whether a blood culture will detect an organism that is present?

• a.The brand of bottle used, because each manufacturer's broth recovers a different set of organisms
• b.The volume of blood placed in each bottle before it is sent for incubation✓
• c.Whether the aerobic bottle or the anaerobic bottle is inoculated first from the collection set
• d.The gauge of the needle, since a wider bore protects the organisms from mechanical damage

Bacteria are present in very small numbers in adult bloodstream infections, so recovery rises with the amount of blood cultured, and an underfilled bottle is a leading cause of a false negative that leaves a septic patient on the wrong antibiotic. Adult bottles are typically filled with eight to ten millilitres each; follow the manufacturer's stated volume. Order of inoculation and needle gauge matter far less.CLSI M47

How should the rubber septum on the top of a blood culture bottle be prepared before the blood is added?

• a.Scrub it with povidone iodine and leave the iodine in place so it keeps working during transport
• b.Wipe it with seventy percent alcohol and let it dry before the needle goes through✓
• c.Remove the plastic flip cap and add the blood at once, since the septum beneath is already sterile
• d.Flame the septum briefly with a lighter to sterilise the surface before the needle passes through

The flip cap keeps the septum clean but does not sterilise it, so the exposed rubber is disinfected with alcohol and allowed to dry before the needle goes through. Iodine is used on the patient's skin rather than on the bottle, because iodine residue can degrade the septum and is unnecessary there. Flaming a bottle top is not an accepted practice in any modern collection standard.CLSI M47

A blood culture set is being collected with a winged blood collection set. Which bottle is inoculated first and why?

• a.The anaerobic bottle, so that no oxygen at all can reach the organisms that need an oxygen-free space
• b.Whichever bottle is nearest, because the two bottles contain exactly the same broth and additive
• c.The anaerobic bottle, because it is the one that has to be filled to the line for the culture to count
• d.The aerobic bottle, because the air in the tubing enters the first bottle attached✓

A winged set holds a small volume of air in its tubing, and that air goes into whichever bottle is attached first. Sending it into the aerobic bottle is harmless, while sending it into the anaerobic bottle works against the very condition that bottle exists to create. When a syringe is used the situation differs, so follow the manufacturer's and the facility's stated sequence.CLSI M47

Why are two blood culture sets usually drawn from two separate venipuncture sites?

• a.Because an organism growing in only one set points toward skin contamination rather than infection✓
• b.Because a single venipuncture site cannot yield enough blood to fill two bottles in an adult patient
• c.Because the laboratory needs a duplicate specimen in case the first one is dropped or mislabelled
• d.Because facility policy requires that every microbiology specimen be collected twice for accuracy

Two sets from two sites let the laboratory interpret what grows. A skin organism such as a coagulase-negative staphylococcus appearing in one set of four bottles usually reflects contamination introduced at that puncture, while the same organism in both sets suggests a real bloodstream infection. Volume, breakage and blanket duplication policies are not the reason.CLSI M47

When does the timing clock start for the specimens of a two-hour glucose tolerance test?

• a.When the fasting specimen is collected, since that is the first sample in the whole series
• b.When the patient arrives at the laboratory and is registered for the appointment that morning
• c.When the patient swallows the last of the glucose solution she was given✓
• d.When the patient begins to drink, because the first mouthful is already being absorbed

The timed specimens are counted from the moment the patient swallows the last of the glucose load, which should be consumed within about five minutes. Starting the clock at the fasting draw or at registration shifts every subsequent specimen, and a glucose reported at the wrong interval can create or hide a diagnosis of diabetes. Exact collection times are documented on each tube.

During a glucose tolerance test the patient asks whether she may step outside for a cigarette between draws. What should the phlebotomist say?

• a.No, smoking is not permitted during the test and she should stay in the area✓
• b.Yes, provided she returns before the next timed specimen is scheduled to be collected
• c.Yes, because nicotine has no measurable effect on any blood glucose measurement at all
• d.Yes, but only if she agrees to have the remaining specimens collected by capillary puncture

Smoking stimulates the release of glucose from stores and can raise the measured value, so it is prohibted for the duration along with eating, drinking anything other than water and chewing gum. The patient also stays where staff can watch for hypoglycemia or fainting. Nicotine is not inert, and switching to capillary collection would change the specimen type mid-test.

A provider orders a trough level for an antibiotic. When is the specimen collected?

• a.Thirty minutes after the dose finishes infusing, when the drug is most evenly distributed
• b.At any convenient point in the dosing interval, as long as the exact time drawn is recorded
• c.Immediately before the next scheduled dose is due to be given to the patient✓
• d.Exactly halfway between two doses, which is the average concentration over the interval

A trough is the lowest concentration in the dosing interval and is measured just before the next dose, which is what tells the prescriber whether the drug stays above the level needed to work. A peak is drawn after the dose at a time that depends on the drug and route. Drawing at a random or midpoint time produces a number that cannot be interpreted, and the exact draw time is always recorded.

Which piece of information must be documented with a therapeutic drug monitoring specimen for the result to be interpretable?

• a.The patient's weight and height, so the laboratory can calculate the expected concentration
• b.The exact time the specimen was drawn and the time of the last dose✓
• c.The route by which the patient prefers to receive the medication in future dosing
• d.The name of the phlebotomist who collected it, which is what makes the result reportable

A drug level means nothing without its position in the dosing interval, so both the collection time and the time the last dose was given are recorded. Without them a prescriber cannot tell a safe trough from a toxic peak. The collector's identity is required on any specimen for traceability but it is not what makes a drug level interpretable, and the laboratory does not calculate expected concentrations from body size.

A blood alcohol level is ordered as part of a legal proceeding. How is the skin prepared?

• a.With seventy percent isopropyl alcohol, which is the routine antiseptic for every venipuncture
• b.With an alcohol-based chlorhexidine scrub, the same preparation used for blood cultures
• c.With no antiseptic at all, because any preparation would invalidate a legal specimen
• d.With a non-alcohol antiseptic such as aqueous benzalkonium chloride or soap and water✓

Alcohol-containing preparations, including alcohol-based chlorhexidine, can be challenged as a source of the measured alcohol, so a non-alcohol antiseptic is used and the choice is documented. The site is still disinfected; leaving it unprepared would create an infection risk and would not help the case. The tube is filled completely and handled under chain of custody.

What does a chain of custody record establish for a forensic specimen?

• a.That the laboratory used an instrument that was calibrated on the morning the specimen was analysed
• b.That the patient consented in writing to the test and understood what it would be used for
• c.That the specimen was collected within the window of time the court order specified
• d.Who had the specimen at every moment from collection to analysis, with signatures and times✓

The chain of custody is an unbroken written record of possession. Each person who handles the sealed specimen signs and dates it, so it can be shown in court that the sample tested is the sample taken and that no one had an unrecorded opportunity to alter it. Consent, calibration and collection timing are all real requirements but each is documented somewhere else.

A patient with hereditary hemochromatosis is scheduled for therapeutic phlebotomy. What is the purpose of the procedure?

• a.To remove a measured volume of blood in order to reduce the patient's iron burden✓
• b.To collect a diagnostic specimen large enough for the full panel of iron studies to be repeated
• c.To obtain a unit of blood that will be transfused into another patient on the same day
• d.To replace the patient's plasma with donor plasma while returning the red cells to the patient

Therapeutic phlebotomy removes red cells, and with them iron, on a physician's order, typically about five hundred millilitres at a session, and it is also used in polycythemia vera to reduce red cell mass. It is treatment, not diagnosis. The blood is generally discarded rather than transfused, and exchanging plasma is a different procedure performed with an apheresis machine.

Which needle gauge is typically used to collect a unit of blood from a volunteer donor?

• a.A 23 gauge, the same as the winged set used for a difficult outpatient venipuncture
• b.A 21 gauge, matching the routine choice for a diagnostic evacuated tube collection
• c.A 16 to 18 gauge, because the wide lumen protects the red cells in a large collection✓
• d.A 25 gauge, since a slower fill gives the anticoagulant in the bag more time to mix in

Donor collection uses a large bore needle so that roughly a pint of blood flows quickly through a wide lumen without shearing the red cells, which preserves the unit for transfusion. A diagnostic gauge would take far too long and would hemolyze the product. A 25 gauge is not used for whole blood collection at all because of the damage it causes.

Which specimen must be kept at body temperature from collection until it reaches the laboratory?

• a.A plasma ammonia, which is transported in an ice slurry to slow the breakdown of the analyte
• b.A serum bilirubin, which is wrapped in foil so that light cannot degrade the pigment in transit
• c.A prothrombin time, which is transported at ordinary room temperature within the stated window
• d.A cold agglutinin titre, which must be kept at 37 degrees Celsius so the antibody stays free✓

Cold agglutinins bind to red cells as the specimen cools, so a sample allowed to reach room temperature loses antibody from the serum and the titre is reported falsely low. The tube is prewarmed and carried in a heat block. Ammonia is chilled, bilirubin is protected from light and a coagulation specimen travels at room temperature, so each of the others names a real requirement for the wrong reason.

How should a specimen that requires chilling be transported to the laboratory?

• a.Buried in a container of solid ice cubes, which hold their temperature longer than anything else
• b.In a household freezer compartment until a courier is available to take it across to the laboratory
• c.In a refrigerator at four degrees, after the tube has first been centrifuged on the collection floor
• d.In a slurry of crushed ice and water, so the whole tube cools evenly without freezing✓

A mixture of ice and water surrounds the tube completely and holds it near zero degrees without letting any part of the specimen freeze. Solid cubes touch the glass at points, so parts of the sample freeze and hemolyze while other parts stay warm. Freezing a whole blood specimen ruptures the cells, and a chilled specimen is not the same as a centrifuged and refrigerated one.

A patient has a central venous catheter and a stat potassium is ordered. Who may draw the specimen from that line?

• a.Only a nurse or other clinician specifically trained and authorised to access central lines✓
• b.The phlebotomist, provided the line is flushed with saline before and after the specimen is drawn
• c.The phlebotomist, as long as a discard volume of at least five millilitres is taken and thrown away
• d.Anyone in the department, because a central line needs no venipuncture skill

Accessing a central line carries risks of infection, air embolism and catheter damage, so it is restricted to staff trained and credentialled for it, and phlebotomists are usually not among them. Flushing and discarding are part of the technique for those who are authorised, not a substitute for the authorisation. A specimen drawn from a line without the discard is also diluted by whatever was infusing.

Before an arterial puncture at the radial site, what does the modified Allen test determine?

• a.Whether the radial artery is large enough to accept the gauge of needle that has been selected
• b.Whether the patient's blood pressure is high enough for the syringe to fill without aspiration
• c.Whether the ulnar artery can supply the hand if the radial artery becomes blocked✓
• d.Whether the patient has enough clotting factor to stop bleeding after the needle is withdrawn

Both hand arteries are compressed until the hand blanches, then the ulnar is released. Colour returning within a few seconds shows collateral circulation, so the hand would survive if the radial artery thrombosed after the puncture. It says nothing about vessel size, blood pressure or coagulation, and arterial puncture itself is performed only by personnel trained and authorised for it.

An arterial blood gas syringe has a small air bubble in it after collection. What must be done?

• a.Expel the bubble at once and cap the syringe, because air alters the measured oxygen✓
• b.Leave the bubble in place, since it will dissolve into the plasma long before analysis begins
• c.Draw the plunger back to enlarge the bubble so it can be seen and reported to the laboratory
• d.Shake the syringe vigorously so the bubble is dispersed evenly

Room air holds much more oxygen and much less carbon dioxide than blood, so a retained bubble raises the measured oxygen and lowers the carbon dioxide, which can make a hypoxic patient look adequately oxygenated. The bubble is expelled immediately, the syringe is capped, the specimen is mixed gently and it goes straight to the laboratory. Shaking hemolyzes the sample.

How long should pressure be held over an arterial puncture site compared with a venous one?

• a.The same length of time, because the puncture wound in the skin is identical in both cases
• b.Less time, because arterial pressure pushes the vessel walls together and seals the site faster
• c.Longer, three to five minutes, and longer still if the patient is anticoagulated✓
• d.No pressure is needed at all if a pressure dressing is applied directly over the site

An artery carries blood under far higher pressure than a vein, so it bleeds longer and can form a large deep hematoma if released early. Continuous firm pressure for three to five minutes is the usual minimum, extended for patients on anticoagulants or with a bleeding disorder, and the site is then rechecked. A dressing alone does not substitute for held pressure.

A serum cortisol is ordered for eight in the morning and the patient arrives at four in the afternoon instead. What should the phlebotomist do?

• a.Draw the specimen now and label it as the eight in the morning collection to keep the order intact
• b.Draw it now without comment, because cortisol is stable and the time of day is irrelevant
• c.Refuse the draw and send the patient home to return at eight in the morning another day
• d.Draw it, record the actual collection time, and notify the provider that the timing has changed✓

Cortisol follows a daily rhythm and is typically highest in the early morning and much lower late in the day, so an afternoon specimen cannot be compared with a morning reference interval. The phlebotomist records the true time and lets the provider decide whether to use it or rebook. Labelling a specimen with a time it was not drawn is falsification of a record.

A patient is scheduled for autologous blood donation. What does that mean?

• a.Blood is collected from a relative whose type has been matched
• b.Blood is collected and separated so that only the plasma is returned to the patient later on
• c.Blood is collected from several donors and pooled into one unit for a single planned operation
• d.The patient's own blood is collected in advance and stored for their own planned surgery✓

In an autologous donation the donor and the recipient are the same person, which removes the risk of a transfusion reaction and of transmitted infection. Blood taken from a named relative or friend is a directed donation, a different arrangement. Pooling units from several donors and returning a separated component are both different procedures with different indications.

Which requirement applies specifically to a blood bank specimen for a type and crossmatch?

• a.The tube is labelled at the bedside with the identifiers plus who drew it and when✓
• b.The tube must be the last one filled in the draw so that no additive can be carried into it
• c.The specimen must be collected by two phlebotomists together
• d.The tube must be transported to the laboratory in an ice slurry to preserve the red cell antigens

Almost every fatal transfusion reaction begins with a specimen labelled for the wrong patient, so blood bank rules add the collector's identity and the date and time to the usual identifiers, and the label goes on at the patient's side before the phlebotomist leaves. Two collectors are not required, the specimen travels at room temperature, and the blood bank tube is not drawn last.

Which specimen requires protection from light between collection and analysis?

• a.A potassium level, because light drives potassium out of the cells
• b.A blood culture set, because light kills the more fragile organisms before they can grow
• c.A serum bilirubin, because light breaks the pigment down and the result reads low✓
• d.A prothrombin time, because light activates the clotting factors and shortens the result

Bilirubin is photosensitive, and a specimen left in daylight or under a phototherapy lamp loses measurable pigment within an hour, which can hide a rising bilirubin in a jaundiced newborn. Carotene, vitamin A, vitamin B6 and folate are handled the same way. Light does not move potassium, kill culture organisms or activate coagulation factors.

A two-hour postprandial glucose is ordered. What instruction does the patient need?

• a.Fast for twelve hours and arrive with nothing to eat or drink since the previous evening
• b.Eat the meal the provider specified, then return exactly two hours after starting it✓
• c.Eat whatever the patient likes at any time, since the two-hour interval is the only variable
• d.Drink the standard glucose solution and wait for two hours

The two-hour postprandial specimen measures how the body handles a defined meal, so the patient eats the prescribed meal and the timing runs from the start of eating. Continuing to fast defeats the purpose, an unspecified meal makes the result impossible to compare, and drinking a measured glucose load is a tolerance test, which is a different order.

A blood culture set drawn from an arm with a running intravenous line grows a skin organism in one bottle only. What is the most likely explanation?

• a.Contamination introduced during collection rather than a true bloodstream infection✓
• b.A genuine bloodstream infection that the second set simply failed to detect on that occasion
• c.Contamination of the culture medium during manufacture, which requires a recall of the lot
• d.Cross contamination in the analyser, which incubates all of the bottles in one shared chamber

A skin organism in one bottle of one set, with the other bottles negative, is the classic pattern of contamination introduced at the puncture, usually from inadequate skin antisepsis or from touching the prepared site. Manufacturing contamination and analyser cross contamination are rare and would show a different pattern, and a true infection generally seeds more than one bottle.

Why is a pre-employment drug screen collected under chain of custody rather than as a routine specimen?

• a.Because the analysis is performed on urine, and urine always requires additional documentation
• b.Because the laboratory charges a higher fee for any test that an employer rather than a patient orders
• c.Because the specimen has to be frozen and logged for temperature
• d.Because the result may cost someone a job and must be defensible if it is challenged✓

A drug screen carries a consequence outside medical care, so the specimen is sealed, initialled and tracked through every transfer, and the donor confirms the seal. That record is what allows the result to withstand a legal challenge. Specimen type, cost and storage temperature do not determine whether chain of custody applies; the use the result will be put to does.

A box of lavender tubes in the drawer passed its expiration date two weeks ago. What is the concern?

• a.The plastic of the tube itself begins to break down and leaches into the blood specimen
• b.The label adhesive fails, so the tube can no longer be labelled
• c.The vacuum and the additive may no longer perform as the manufacturer guarantees✓
• d.Nothing, provided the box was stored in a cool dry place away from sunlight

An expiration date certifies the draw volume and the additive activity, so an expired tube can underfill or fail to anticoagulate properly, and a short-filled EDTA tube gives a falsely low hematocrit while a poorly anticoagulated one clots. Expired stock is removed from service rather than used carefully. Storage conditions matter but do not extend the date, and the plastic does not degrade into the sample.

What is the function of the rubber sleeve that covers the back end of a multisample needle?

• a.It cushions the tube stopper so the glass cannot crack when the tube is pushed onto the needle
• b.It closes over the needle between tubes so blood does not leak while tubes are changed✓
• c.It holds the additive that will be released into the first tube attached to the holder
• d.It keeps the needle sterile while it is inside the patient's vein during the collection

The sleeve is a one-way valve. Tube pressure pushes it back so blood enters, and it springs closed the moment the tube is removed, which is what allows several tubes to be filled through one venipuncture without blood escaping into the holder. It carries no additive, provides no cushioning and plays no part in sterility once the needle is in the vein.

A blood smear is made from an EDTA tube using the wedge technique. Which detail matters most for a usable slide?

• a.The drop is placed at the centre of the slide so the film spreads evenly in both directions at once
• b.The spreader slide is held at roughly a thirty degree angle and pushed with one smooth motion✓
• c.The slide is warmed on a slide dryer before the drop of blood is placed on its surface
• d.The film is spread slowly enough that it covers the entire slide from end to end

A shallow, steady push at about thirty degrees produces a film with a feathered edge, which is the thin area where the cells lie in a single layer and can be identified and counted. A steeper angle makes the film short and thick, a slower push makes it too long, and covering the whole slide leaves no feathered edge at all. The drop goes near one end, not the centre.

A blood pressure cuff is used in place of a tourniquet on a patient with difficult veins. How should it be used?

• a.Inflate it above the patient's systolic pressure so the vein fills fully
• b.Inflate it to the patient's diastolic pressure and leave it there until every tube is filled
• c.Leave it deflated and rely on the width of the cuff alone to compress the superficial veins
• d.Inflate it below the diastolic pressure and release it within the same one minute limit✓

A cuff works like a tourniquet only if it obstructs venous return while arterial inflow continues, which means a pressure below diastolic. Inflating above systolic stops arterial flow altogether and the vein does not fill. The one minute limit still applies, because hemoconcentration develops just as it does under a rubber tourniquet, and a deflated cuff compresses nothing.

Which vein is generally the second choice for antecubital venipuncture when the median cubital cannot be used?

• a.The cephalic vein, which lies on the thumb side of the arm✓
• b.The basilic vein, because it is usually the most visible of the three
• c.The radial artery, provided the modified Allen test is normal
• d.Any vein on the inner wrist, where the vessels run straighter

The order of preference runs median cubital, then cephalic, then basilic. The cephalic lies laterally and can be harder to anchor because it tends to roll, but it is away from the median nerve and the brachial artery that make the basilic the last resort. An artery is never a substitute for a vein in routine collection, and the inner wrist is avoided entirely.

A phlebotomist must draw a patient who is on contact precautions in an isolation room. What happens to the collection tray?

• a.The whole tray is carried in and wiped down with disinfectant on the way back out of the room
• b.The tray is carried in but placed on the floor rather than on any surface in the room
• c.The tray stays outside; only the supplies needed for that draw are taken in✓
• d.The tray is carried in and left in the room until the patient is discharged from isolation

Anything taken into an isolation room is treated as contaminated, so the shared tray stays outside and the phlebotomist carries in only what the draw requires, plus a little margin. Wiping a tray that has sat on an isolation surface is less reliable than never exposing it, the floor is the most contaminated surface in any room, and leaving a shared tray behind removes it from service.

A waived point of care prothrombin time device is used in an anticoagulation clinic. What does the CLIA waived designation mean?

• a.The test may be performed without any quality control, documentation or operator training at all
• b.The result carries no clinical weight and always has to be confirmed by the central laboratory
• c.The test is simple enough to have a low risk of erroneous result, but rules still apply✓
• d.The facility does not need a CLIA certificate of any kind in order to perform the test

A waived test is one the manufacturer has shown to be simple and low risk when the instructions are followed, and the facility still needs a CLIA certificate of waiver, trained operators, manufacturer quality control and records. Waived results are used clinically. Skipping quality control, or believing that no certificate is needed, are the two errors that turn a waived test into a citation.

A requisition asks for a test the phlebotomist has never heard of and gives no tube type. What should be done first?

• a.Draw one tube of every colour available so that the laboratory is certain to have what it needs
• b.Check the laboratory's specimen requirements, and call the laboratory if it is still unclear✓
• c.Draw a lavender tube, since whole blood can be used for the widest range of tests
• d.Ask the patient which tube was used the last time this same test was ordered

Every laboratory publishes a specimen requirement list or online directory giving tube type, volume, handling and stability for each test, and a phone call resolves anything the directory does not. Drawing a full rainbow of tubes takes blood the patient does not need to give, guessing at a lavender wastes the draw when serum is required, and a patient is not a source of specimen requirements.

Why does prolonged tourniquet application raise the measured total protein and calcium?

• a.Because the pressure squeezes protein out of the muscle tissue and into the vein below the cuff
• b.Because the vein warms under the tourniquet and warm plasma carries more protein in solution
• c.Because the tourniquet stops arterial inflow, so the cells consume the remaining water
• d.Because water and small molecules leave the vessel while large molecules stay behind✓

Obstructed venous return raises pressure inside the vessel, and water and small solutes filter out into the tissue while proteins and anything bound to them, including much of the calcium, are held back. The remaining plasma is concentrated, so protein, calcium, cholesterol, iron and cell counts all read high. Releasing the tourniquet within a minute keeps the effect clinically negligible.

A phlebotomist draws blood into a syringe and then fills a citrate tube, a heparin tube and an EDTA tube. In what order should the tubes be filled?

• a.Citrate, then heparin, then EDTA, which is the same relative order as an evacuated tube draw✓
• b.EDTA first, because the cells begin to clot in the syringe and the count is the most fragile result
• c.Heparin first, then citrate, then EDTA, because heparin is the least affected by any delay
• d.Any order, since the blood is already mixed in the barrel and no carryover can occur

The blood in a syringe begins to clot from the moment it is drawn, so the coagulation tube is filled first and the transfer is completed quickly. The relative order of the tubes does not change with the collection method. Carryover is no longer the reason, but clot formation is, and it argues for the same sequence rather than a different one.

How long should an adhesive bandage stay on after a routine venipuncture on an adult?

• a.Until the patient's next appointment, so the site is protected from any knock in the meantime
• b.Around fifteen minutes, or longer if the patient bruises easily or takes an anticoagulant✓
• c.Ten seconds, just long enough for the phlebotomist to confirm the bleeding has already stopped
• d.Overnight, because a venipuncture wound needs a full night to close completely

A quarter of an hour is the usual advice, with longer for a patient who bleeds or bruises easily, and the patient is told to keep the arm straight and avoid heavy lifting with it for a while. Removing it within seconds risks the site reopening, and leaving an adhesive on for a day irritates the skin without adding any protection.

A patient in a wheelchair needs an outpatient blood draw. What is the safest arrangement?

• a.Ask the patient to stand and lean against the drawing chair for the few seconds the draw takes
• b.Draw the patient in the wheelchair without touching the brakes, so it can be moved in an emergency
• c.Lock the wheelchair brakes and support the arm, or transfer the patient with help if needed✓
• d.Lift the patient into the phlebotomy chair without assistance so that no time is lost

The chair is immobilised and the arm is supported on a firm surface so neither the patient nor the phlebotomist has to hold a position that could slip. Where the facility requires a transfer it is done with help and with the correct equipment. Asking a wheelchair user to stand, leaving the brakes off and lifting a patient alone all invite a fall or a back injury.

Which practice best prevents a wrong-patient specimen in a busy outpatient drawing area?

• a.Pre-labelling the tubes for the next three patients so that no label can be mixed up later
• b.Labelling each tube at the chair after the draw and comparing the label with the patient✓
• c.Writing the patient's initials on the tube and adding the full label at the end of the shift
• d.Keeping each patient's tubes in a separate rack and labelling the whole rack at once

Labels are applied one patient at a time, at the point of collection, and read back against the requisition and the patient before the phlebotomist moves on. Pre-labelling puts a correct label on the wrong blood the first time a patient is called out of order, and any scheme that defers labelling relies on memory, which is what fails on a busy morning.

A phlebotomist notices that the sharps container in the drawing room is filled past the marked line. What should be done?

• a.Press the contents down carefully with a gloved hand so that more room becomes available
• b.Continue using it until the end of the shift and raise it with the lead afterwards
• c.Empty the container into the biohazard waste bin and put the empty container back in place
• d.Close and replace it, and do not use it again once it has reached the fill line✓

Overfilling is how sharps protrude from the opening and injure the next person to use the container or the staff who transport it, so a container is sealed and exchanged when it reaches the manufacturer's line, usually about three quarters full. Pressing contents down puts a hand directly over exposed needles, and a sharps container is never emptied on site.