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AMT CMLA practice questions

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Question 1Specimen Collection and Handling

When several evacuated tubes are ordered and blood cultures are not requested, which tube is collected first?

  1. Green sodium heparin
  2. Light blue sodium citrate Correct answer.
  3. Gold serum separator
  4. Lavender EDTA

Explanation

Coagulation tubes must be drawn before any tube containing an additive, because carryover of clot activators, heparin, or EDTA can invalidate coagulation results. Blood cultures, when ordered, are always drawn before all tubes. The remaining tubes follow the standard order of serum, heparin, EDTA, then fluoride oxalate.

Question 2Specimen Collection and Handling

What is the maximum time a tourniquet should remain in place during venipuncture?

  1. 5 minutes
  2. 1 minute Correct answer.
  3. 30 seconds
  4. 2 minutes

Explanation

A tourniquet left on longer than one minute causes hemoconcentration, stasis, and hemolysis, which falsely elevate potassium, protein, and enzyme results. If more time is needed, the tourniquet should be released and reapplied after a short interval.

Question 3Specimen Collection and Handling

Which needle gauge is standard for a routine adult antecubital venipuncture?

  1. 21 gauge Correct answer.
  2. 18 gauge
  3. 25 gauge
  4. 23 gauge

Explanation

A 21-gauge needle provides adequate flow for most tube volumes while causing minimal trauma to the vein. Larger 18-gauge needles are used when large volumes or rapid flow are needed, and 23- to 25-gauge needles are reserved for small or fragile veins.

Question 4Specimen Collection and Handling

Which additive is present in a lavender-stoppered evacuated tube?

  1. Sodium fluoride
  2. Sodium citrate
  3. Sodium heparin
  4. EDTA Correct answer.

Explanation

Lavender tubes contain EDTA, which chelates calcium and prevents coagulation by blocking the clotting cascade. EDTA preserves cell morphology and is therefore the tube of choice for hematology testing such as a complete blood count.

Question 5Specimen Collection and Handling

Where should a capillary puncture be performed on an adult finger?

  1. Across the nail bed
  2. On the palmar surface of the thumb
  3. On the center of the fingertip pad
  4. On the lateral side of the distal phalanx Correct answer.

Explanation

Puncturing the lateral portion of the distal phalanx, perpendicular to the skin ridges, avoids the dense nerve endings and thicker tissue of the fingertip center and yields better blood flow. The thumb is avoided because its pad is thicker and more sensitive.

Question 6Specimen Collection and Handling

When must a specimen label be applied to a blood tube?

  1. At the processing station in the laboratory
  2. Before entering the patient's room
  3. At the bedside immediately after collection Correct answer.
  4. After the tube has been centrifuged

Explanation

Labeling at the bedside immediately after filling the tube links the specimen to the patient while the collector is still present to verify identity. Labeling away from the bedside is a leading cause of mislabeled specimens and is a reason for rejection.

Question 7Specimen Collection and Handling

What is the correct handling of a used venipuncture needle?

  1. Place it directly into a sharps container without recapping Correct answer.
  2. Recap it and place it in a biohazard bag
  3. Lay it on the tray until the draw is complete
  4. Break the needle off the hub before disposal

Explanation

Used needles go directly into a rigid, puncture-resistant sharps container without recapping, because recapping is the most common cause of needlestick injuries. Needles should never be broken, bent, or left loose on a work surface.

Question 8Specimen Collection and Handling

Which vein is preferred for routine venipuncture in the antecubital area?

  1. Median cubital vein Correct answer.
  2. Dorsal hand veins
  3. Basilic vein
  4. Cephalic vein

Explanation

The median cubital vein is large, well anchored, and lies away from major arteries and nerves, making it the first choice for venipuncture. The basilic and cephalic veins are acceptable alternatives but are more mobile or closer to adjacent structures.

Question 9Specimen Collection and Handling

Which site is appropriate for a heel puncture in an infant?

  1. The center of the heel pad
  2. The posterior curvature of the heel
  3. The arch of the foot
  4. The medial or lateral plantar surface Correct answer.

Explanation

Heel punctures are performed on the medial or lateral plantar surface, where the tissue is thick enough to avoid the bone. The center of the heel is avoided because the calcaneus lies close to the skin and puncture there can cause osteomyelitis.

Question 10Specimen Collection and Handling

What does a gold-stoppered serum separator tube contain?

  1. Clot activator and a separator gel Correct answer.
  2. Potassium oxalate and sodium fluoride
  3. Sodium citrate and a gel barrier
  4. Heparin and a gel barrier

Explanation

Gold or red-gray serum separator tubes contain silica clot activator and a thixotropic gel that forms a barrier during centrifugation. The activator speeds clotting, and the gel keeps serum separated from cells during transport.

Question 11Specimen Collection and Handling

How is a 24-hour urine collection correctly performed?

  1. Discard the first morning void, then collect all urine for 24 hours Correct answer.
  2. Collect only the first morning void on two consecutive days
  3. Collect a single random specimen at the same time each day
  4. Collect the first morning void, then collect all urine for 24 hours

Explanation

The collection begins by discarding the first morning void, which reflects urine formed before the start time, and then includes every void up to and including the first void at the same time the next day. The container is kept refrigerated or chemically preserved throughout.

Question 12Specimen Collection and Handling

What instructions should be given for a clean-catch midstream urine specimen?

  1. Cleanse the area, void briefly, collect midstream Correct answer.
  2. Collect the first portion of the stream in a sterile cup
  3. Collect the entire void in a 24-hour container
  4. Collect urine from an indwelling catheter drainage bag

Explanation

The patient cleans the genital area, begins voiding into the toilet, and collects the midstream portion in a sterile container before finishing into the toilet. This flushes flora from the distal urethra and reduces contamination of the culture.

Question 13Specimen Collection and Handling

Which dietary items should a patient avoid before a guaiac fecal occult blood test?

  1. Caffeinated beverages and chocolate
  2. All dairy products and citrus fruits
  3. Red meat, certain raw vegetables, and vitamin C Correct answer.
  4. Nothing, because no dietary restriction is required

Explanation

Red meat contains heme that mimics blood, some raw vegetables contain peroxidases that cause false positives, and vitamin C can cause false negatives by inhibiting the indicator. Restrictions are typically followed for three days before collection.

Question 14Specimen Collection and Handling

Why must a coagulation tube be filled to its stated draw volume?

  1. Fill volume matters only for heparinized tubes
  2. Short draws alter the blood-to-anticoagulant ratio Correct answer.
  3. The tube must be overfilled to ensure complete clotting
  4. It may be half filled if the patient is anemic

Explanation

Coagulation tubes are calibrated for a 9:1 ratio of blood to 3.2% sodium citrate. A short draw leaves excess citrate, which binds calcium and falsely prolongs clotting times such as the PT and aPTT.

Question 15Specimen Collection and Handling

When blood gases are not required, which microtainer is filled first in a capillary collection?

  1. Lavender EDTA tube Correct answer.
  2. Green heparin tube
  3. Serum tube with clot activator
  4. Gray fluoride oxalate tube

Explanation

The capillary order of draw differs from the venous order: blood gas tubes come first, followed by EDTA, then other additive tubes, and serum last. EDTA is collected early because it requires the least volume and because clotting begins quickly in capillary blood.

Question 16Specimen Collection and Handling

Which practice is a common cause of hemolysis in a collected blood specimen?

  1. Centrifuging at the recommended speed
  2. Filling the tube to the marked volume
  3. Allowing the tube to clot at room temperature
  4. Pulling forcefully on the syringe plunger Correct answer.

Explanation

Excessive force during aspiration damages red cells and releases hemoglobin and intracellular potassium into the specimen. Small-bore needles, vigorous shaking, and drawing through an existing hematoma are other common causes.

Question 17Specimen Collection and Handling

A blood tube arrives in the laboratory with no patient label. What is the correct action?

  1. Store it in the refrigerator for 24 hours
  2. Label it from the accompanying requisition
  3. Reject it and request a new specimen Correct answer.
  4. Process it and notify the nursing unit afterward

Explanation

A specimen that is not labeled at the time of collection cannot be reliably linked to the patient and must be rejected. Specimen identity cannot be reconstructed from a requisition after the fact, so a new collection is required.

Question 18Specimen Collection and Handling

Which instruction applies to a patient scheduled for a 2-hour glucose tolerance test?

  1. Eat a high-carbohydrate breakfast before arrival
  2. Fast 8 to 12 hours beforehand, drinking only water Correct answer.
  3. Limit fluid intake to 4 ounces during the test
  4. Exercise lightly between blood draws

Explanation

The patient fasts for 8 to 12 hours before the test and may drink water only, then remains seated and avoids smoking or exercise during the test. Activity and smoking can alter glucose and insulin values between draws.

Question 19Specimen Collection and Handling

During a venipuncture, a rapidly enlarging swelling appears at the puncture site. What should the collector do?

  1. Advance the needle deeper to reach the vein
  2. Remove the needle and apply firm pressure at the site Correct answer.
  3. Tighten the tourniquet further to slow the bleeding
  4. Continue and collect the sample as quickly as possible

Explanation

The swelling indicates a hematoma from blood leaking into surrounding tissue, usually because the needle penetrated through the vein. The needle is withdrawn and firm pressure is applied for several minutes to limit the size of the hematoma.

Question 20Specimen Collection and Handling

A patient becomes pale and dizzy with the needle still in place. What is the appropriate response?

  1. Complete the draw as quickly as possible
  2. Apply a cold compress to the antecubital area
  3. Remove the tourniquet and lower the patient's head Correct answer.
  4. Have the patient sit upright and drink water

Explanation

These signs suggest a vasovagal reaction, so the tourniquet and needle are removed promptly and the patient is positioned supine or with the head lowered to restore cerebral blood flow. A cold compress and monitoring follow once the patient is safe.

Question 21Specimen Collection and Handling

How should a specimen for cold agglutinin testing be handled after collection?

  1. Keep the specimen at 37°C and deliver immediately Correct answer.
  2. Refrigerate the specimen at 4°C overnight
  3. Place the specimen on wet ice for transport
  4. Freeze the separated serum at -20°C

Explanation

Cold agglutinins bind red cells at room temperature and below, so the specimen must be kept warm at 37°C from collection through testing. Chilling the sample allows antibody binding and falsely lowers the measured titer.

Question 22Specimen Collection and Handling

Which collection and transport condition is correct for a plasma ammonia specimen?

  1. Sodium citrate tube protected from light
  2. Serum separator tube at room temperature
  3. EDTA tube on ice, analyzed promptly Correct answer.
  4. Heparin tube refrigerated for 24 hours

Explanation

Ammonia rises rapidly in shed blood because red cells release it, so the specimen is collected in an EDTA tube, chilled on ice, and separated and analyzed without delay. Delay or warming produces falsely elevated results.

Question 23Specimen Collection and Handling

When is a trough level for therapeutic drug monitoring collected?

  1. 30 minutes after the dose is given
  2. Just before the next scheduled dose Correct answer.
  3. At any convenient time during the day
  4. Immediately after the infusion ends

Explanation

The trough reflects the lowest concentration of the drug and is drawn just before the next dose is administered. Collecting at other times makes the result uninterpretable against therapeutic ranges established for trough specimens.

Question 24Specimen Collection and Handling

An arterial blood gas specimen cannot be analyzed right away. What is the appropriate handling?

  1. Centrifuge, then refrigerate the plasma for 2 hours
  2. Freeze the syringe until the analyzer is available
  3. Store at room temperature and analyze within 4 hours
  4. Place on ice and analyze within 15 to 30 minutes Correct answer.

Explanation

Arterial blood gas samples are chilled to slow cellular metabolism and are analyzed as soon as possible, generally within 15 to 30 minutes. Prolonged storage changes pH, pCO2, and pO2 and produces misleading results.

Question 25Specimen Collection and Handling

What is required when collecting a specimen for legal or forensic purposes?

  1. Only the laboratory director may handle it
  2. Each transfer must be documented with signatures Correct answer.
  3. The specimen may be discarded after 24 hours
  4. It should be stored at room temperature indefinitely

Explanation

Forensic specimens require an unbroken chain of custody, meaning every hand-to-hand transfer is recorded with the date, time, and signatures of the people involved. Any gap in documentation can make the result inadmissible.

Question 26Specimen Collection and Handling

What is the maximum time a tourniquet should remain in place during a routine venipuncture?

  1. 10 minutes
  2. 5 minutes
  3. 1 minute Correct answer.
  4. 3 minutes

Explanation

Stasis beyond about 1 minute produces hemoconcentration and hemolysis, falsely raising potassium, total protein, and cell counts. The tourniquet should be released as soon as blood flow is established.

Question 27Specimen Collection and Handling

Before drawing any blood specimen, how should the collector verify patient identity?

  1. By asking the patient to spell their last name aloud
  2. By matching two independent identifiers against the requisition Correct answer.
  3. By confirming the patient's room number and bed assignment with the nurse
  4. By comparing the requisition with the previous day's tube labels

Explanation

Two independent identifiers, such as full name and date of birth or a unique identification number, must match the requisition and the patient's identification band. Room or bed location is not an identifier because patients move and rooms are reassigned.

Question 28Specimen Collection and Handling

Which collection instruction is appropriate for a routine sputum culture?

  1. A deep-cough specimen on waking, after mouth rinsing Correct answer.
  2. Collect the specimen after an overnight fast without fluids
  3. Collect the specimen after a saline gargle
  4. Collect a sample of saliva after rinsing the mouth with water

Explanation

A first-morning specimen obtained by deep coughing yields the most concentrated sample from the lower respiratory tract. Rinsing the mouth first reduces contamination with oral flora and food debris, and saliva is not an acceptable substitute.

Question 29Specimen Collection and Handling

A clean-catch urine specimen for culture cannot reach the laboratory within 30 minutes. What should be done with the specimen?

  1. Incubate it at 37 degrees Celsius until transport
  2. Add a preservative tablet to the container
  3. Leave it at room temperature until the end of the shift
  4. Refrigerate the specimen until it is transported Correct answer.

Explanation

Urine is an excellent growth medium, so a delay allows commensal organisms to multiply and produces a false-positive culture. Refrigerating at 2 to 8 degrees Celsius slows bacterial growth until the specimen reaches the laboratory.

Question 30Specimen Collection and Handling

During a single venipuncture, blood culture bottles, a light blue citrate tube, and a lavender EDTA tube are to be collected. Which is drawn first?

  1. The lavender EDTA tube
  2. The light blue citrate tube
  3. The blood culture bottles Correct answer.
  4. The order makes no difference

Explanation

The standard order of draw places blood culture bottles before all tubes so that the needle and site are least contaminated when the sterile culture is inoculated. Coagulation tubes follow cultures, and EDTA tubes are collected after serum and heparin tubes.

Question 31Specimen Collection and Handling

How should a lavender-stoppered EDTA tube be handled immediately after blood is drawn into it?

  1. Allow it to clot upright for 30 minutes
  2. Centrifuge it at the collection site
  3. Invert it gently 8 to 10 times Correct answer.
  4. Shake it vigorously for 30 seconds

Explanation

EDTA must contact the whole blood evenly to prevent microclots that clog analyzers and alter cell counts, so the tube is inverted gently the number of times specified by the manufacturer. Vigorous shaking causes hemolysis and is never appropriate.

Question 32Specimen Collection and Handling

A venous blood specimen for lactate is collected in a gray-stoppered tube. How should it be handled after collection?

  1. Place it immediately in an ice-water slurry Correct answer.
  2. Protect it from light and keep it at room temperature
  3. Warm it to 37 degrees Celsius before transport
  4. Allow it to clot before centrifugation

Explanation

Cells in a whole-blood sample continue to metabolize glucose and generate lactate after collection, so chilling slows glycolysis and preserves the lactate value. The specimen is transported on ice and separated promptly according to the laboratory's instructions.

Question 33Specimen Collection and Handling

A specimen of aspirated fluid is being sent for anaerobic culture. Which transport condition is correct?

  1. Use an anaerobic transport vial kept at room temperature Correct answer.
  2. Expose the specimen to room air to prevent overgrowth
  3. Place the swab in a dry, sterile container and send it at once
  4. Refrigerate the syringe until it reaches the laboratory

Explanation

Obligate anaerobes die when exposed to oxygen, so the specimen must be maintained in an oxygen-free environment and kept at room temperature. Refrigeration further reduces the recovery of fastidious anaerobes.

Question 34Specimen Collection and Handling

Which instruction should a patient receive for a semen analysis specimen?

  1. Freeze the specimen immediately after collection
  2. Collect the specimen at home in a nonsterile container
  3. Refrigerate the specimen and deliver it within 24 hours
  4. Keep the specimen warm and deliver it within one hour Correct answer.

Explanation

Sperm motility and viability decline with time and with temperature shock, so the specimen is collected in a sterile container and kept near body temperature until it reaches the laboratory within about an hour. Refrigeration or freezing destroys the motility that the assay measures.

Question 35Specimen Collection and Handling

Which tube is specified for collection of a blood specimen for trace element testing such as lead?

  1. A light blue citrate tube
  2. A royal-blue-stoppered tube verified as metal-free Correct answer.
  3. A green-stoppered heparin tube
  4. A lavender-stoppered EDTA tube from the routine rack

Explanation

Trace element testing requires tubes that are certified to be free of the metals being measured, which is what the royal-blue stopper designates. Routine tubes and their stoppers can leach or contain metals that contaminate the specimen.

Question 36Specimen Collection and Handling

A serum specimen arrives in the laboratory grossly hemolyzed and a potassium level was requested. What is the correct laboratory action?

  1. Report the potassium with a comment noting the hemolysis
  2. Reject the specimen and request a new collection Correct answer.
  3. Analyze the specimen after a second centrifugation
  4. Dilute the specimen and reanalyze it

Explanation

Potassium concentration inside red cells is many times higher than in serum, so hemolysis releases it into the specimen and produces a falsely elevated result. No analytical correction is reliable, so the specimen must be rejected and recollected.

Question 37Specimen Collection and Handling

Which specimen is preferred for culture of a deep surgical wound?

  1. A superficial swab of the wound surface
  2. An aspirate or tissue from the wound base Correct answer.
  3. A swab transported in viral transport medium
  4. A swab of the purulent drainage sent in a dry sterile tube

Explanation

Deep tissue or aspirated fluid reflects the organisms actually infecting the wound, whereas a surface swab mostly recovers colonizing flora. Swabs also carry a small volume and dry out, reducing recovery of fastidious organisms.

Question 38Specimen Collection and Handling

Blood is being collected for cryoglobulin testing. Which handling is required from collection through centrifugation?

  1. Protect the tube from light and store it at 4 degrees Celsius
  2. Keep the specimen at 37 degrees Celsius until the serum is separated Correct answer.
  3. Place the tube in an ice bath immediately after collection
  4. Allow the specimen to clot at room temperature for two hours

Explanation

Cryoglobulins precipitate when cooled and redissolve on warming, so the specimen must stay at 37 degrees Celsius during clotting, transport, and separation. If it cools, the precipitate is lost or misclassified and the result becomes falsely negative.

Question 39Specimen Collection and Handling

A patient is receiving an infusion through a catheter in the right antecubital fossa, and a STAT chemistry panel is ordered. Where should the blood be drawn?

  1. From the right arm, just above the catheter tip
  2. From the right hand on the same side as the catheter
  3. From the tubing of the infusion line after flushing
  4. From the opposite arm, away from the infusion Correct answer.

Explanation

Blood drawn near an infusing line is diluted and contaminated by the infusate, which can grossly alter electrolyte and glucose results. The opposite arm is used; if that is impossible, the line is stopped and a specimen is drawn below the site after an adequate discard.

Question 40Specimen Collection and Handling

Which technique is correct when preparing a newborn screening filter-paper card?

  1. Layer blood on both sides of the paper to fill the circles
  2. Apply a single drop that fills one circle completely Correct answer.
  3. Allow the card to dry in a sealed plastic bag
  4. Apply several small drops to each circle until it is full

Explanation

Each circle must be saturated by a single application of blood that soaks through to the back, because layering produces nonuniform spots that invalidate the assay. The card is then air-dried flat, away from heat and sunlight, and never sealed while wet.

Question 41Specimen Processing and Preparation

A patient has orders for blood cultures, a coagulation panel, and a chemistry panel. Which specimen must be collected first?

  1. Blood culture bottles Correct answer.
  2. Lavender EDTA tube
  3. Gold serum separator tube
  4. Light blue sodium citrate tube

Explanation

Blood cultures are drawn first so that skin flora or bacteria introduced during the draw are not flushed into the bottles from a tube's stopper or additive. Collecting cultures after other tubes increases the risk of contaminating the culture with organisms from the collection set.

Question 42Specimen Processing and Preparation

Which additive is present in a lavender-stoppered evacuated blood tube?

  1. Dipotassium EDTA Correct answer.
  2. Sodium citrate
  3. Sodium fluoride
  4. Sodium heparin

Explanation

Lavender-stoppered tubes contain EDTA, which chelates calcium and prevents coagulation, making them suitable for hematology testing such as complete blood counts. EDTA preserves cell morphology better than heparin.

Question 43Specimen Processing and Preparation

A blood tube arrives in the laboratory with no patient name or identifier on it. What is the correct action?

  1. Reject it and request a recollect Correct answer.
  2. Put a label on it using the requisition
  3. Accept it if the courier identifies the patient
  4. Label it after the patient confirms the name

Explanation

Specimens must be labeled at the time of collection with two patient identifiers; a laboratory that labels an unlabeled tube breaks the chain of identification and risks a misdiagnosis. The specimen must be rejected and a new sample collected.

Question 44Specimen Processing and Preparation

Which additive tube is the appropriate choice for a fasting glucose specimen?

  1. Dipostassium EDTA
  2. Sodium fluoride with potassium oxalate Correct answer.
  3. Sodium citrate
  4. Lithium heparin

Explanation

Gray tubes contain sodium fluoride, which blocks glycolysis, plus potassium oxalate as an anticoagulant, preserving glucose values during transport. Heparinized plasma continues to consume glucose at room temperature.

Question 45Specimen Processing and Preparation

Which needle gauge is standard for a routine adult venipuncture with a multi-sample system?

  1. 21 gauge Correct answer.
  2. 23 gauge
  3. 18 gauge
  4. 25 gauge

Explanation

A 21-gauge needle provides good flow while limiting hemolysis and vessel trauma, making it the usual choice for adult venipuncture. Larger needles are reserved for donation or rapid transfusion, and smaller gauges increase hemolysis.

Question 46Specimen Processing and Preparation

Which urine specimen is preferred for a routine bacterial culture?

  1. Random specimen after exercise
  2. Specimen drained from a collection bag
  3. Midstream clean-catch specimen Correct answer.
  4. First-voided specimen

Explanation

A midstream clean-catch specimen minimizes contamination from perineal flora so that culture results reflect bladder organisms. The initial void is discarded and the midstream portion is collected into a sterile container.

Question 47Specimen Processing and Preparation

Where should a heel puncture be made on an infant?

  1. The lateral edge of the heel
  2. The posterior surface of the heel
  3. The center of the heel pad
  4. The medial plantar surface Correct answer.

Explanation

The medial or lateral plantar surface of the heel provides a safe area with adequate capillary bed while avoiding the calcaneus. Puncturing the central heel risks osteomyelitis of the heel bone.

Question 48Specimen Processing and Preparation

How long should a serum separator tube clot before centrifugation when processed at room temperature?

  1. About 5 minutes
  2. About 2 hours
  3. About 30 minutes Correct answer.
  4. About 6 hours

Explanation

Serum tubes need roughly 30 minutes at room temperature for complete clot formation before centrifugation. Spinning too early leaves fibrin strands that can clog analyzers or produce erroneous results.

Question 49Specimen Processing and Preparation

How should tubes be arranged in a centrifuge before spinning?

  1. Only one tube per run for accuracy
  2. Balance only required above 3000 rpm
  3. All tubes placed on one side of the rotor
  4. Opposite tubes balanced to equal weight Correct answer.

Explanation

Tubes must be placed opposite one another with equal weight so the rotor spins without vibration. An unbalanced load can damage the centrifuge and disrupt the separation barrier.

Question 50Specimen Processing and Preparation

Which instruction should be given to a patient beginning a 24-hour urine collection?

  1. Collect every void including the first morning void
  2. Discard the first void; refrigerate the rest Correct answer.
  3. Collect the first morning void and refrigerate it
  4. Discard the first and last voids of the period

Explanation

The first morning void is discarded and the collection timer starts at that moment, so that the 24-hour window captures a complete cycle. The container is kept refrigerated or on ice throughout collection.