8.2 Post-Care, Labeling, Transport, Processing, and Send-Outs

AMT splits post-draw work into three competencies: proper post care of venous puncture sites (II.3.B.11), handle blood samples to maintain specimen integrity (II.3.B.12), and follow standard operating procedures for labeling, transporting, and processing specimens, including transporting to reference laboratories (II.3.B.13). The handling standard on AMT CMLA-REF-2025-1 is CLSI PRE04, Handling, transport, processing, and storage of blood specimens for routine laboratory examinations (1st edition, 2023). Identification rules remain CLSI PRE01 (Chapter 6.3). PRE04 is what happens after the label is on: pressure, light, ice, centrifuges, pneumatic tubes, and send-out boxes.

Quick Answer: Direct pressure, then a bandage; watch for hematoma; no heavy lifting with that arm. Label in the patient's presence. Protect bilirubin from light. Put ammonia and lactate in ice slurry per SOP—not against ice cubes, not "all tubes on ice." Skip the pneumatic tube when SOP excludes the specimen. Accession, spin, aliquot, and ship send-outs as biohazard with temperature monitors.

Post-care of the venous puncture site

When the last tube is filling, release the tourniquet if it is still on. Remove the needle, activate the safety device, and apply direct pressure with clean gauze as the needle leaves the skin. Pressure is your job first, not the patient's. A common outdated habit is telling the patient to flex the elbow over the gauze; bending the arm can make a hematoma by holding the vein open at the puncture. Keep the arm straight and press.

Hold pressure until bleeding stops—often about 3–5 minutes for a routine draw, longer if the patient is on anticoagulants, has a coagulopathy, or had a traumatic stick. Then inspect the site: it should not be expanding, leaking, or forming a raised bruise. Apply a bandage per policy. Instruct the patient to leave the bandage on for the time your SOP states (commonly 15 minutes or more), to avoid heavy lifting or a heavy bag on that arm for several hours, and to apply pressure and notify staff if the site swells, bleeds through, or becomes numb.

Watch for syncope on standing. Post-care is not finished when the tubes are in the rack. If a hematoma is forming, apply firm pressure longer, consider a cold pack per policy after bleeding is controlled, and document. Do not discharge an expanding bruise.

Labeling in the processing chain

Chapter 6.3 covered two identifiers, active ID, and labeling at the side of the patient. PRE04 assumes that already happened. In processing, keep that identity attached:

• Do not peel a label to "fix" a misspelling at the centrifuge.
• Do not accession a tube whose name, date of birth, or medical record number disagrees with the requisition.
• Add accession numbers or barcodes in addition to, not instead of, the patient identifiers.
• Date, time, and collector ID stay with the specimen into the analyzer and the send-out bag.

If you must aliquot, label the aliquot tube before you pour or pipette, matching the primary identifiers. An unlabeled pour-off in a work rack is a lost specimen.

Integrity: light, temperature, time, and motion

Specimen integrity means the analyte in the tube still represents the patient. The four classic destroyers after collection are light, wrong temperature, delay on cells, and rough handling.

Light protection: Bilirubin (especially neonatal) photodegrades in daylight and fluorescent light—wrap the tube in foil or use an amber container immediately. Some vitamins (commonly vitamins A, B6, B12, and folate) and porphyrins are also light-sensitive. A clear bag on a windowsill is not protection.

Ice slurry, refrigerated, ambient, and frozen are four different instructions, not a temperature ladder you pick for convenience:

| Handling | What it is | Typical CMLA examples (follow SOP/IFU) | Classic error | |---|---|---| | Ice slurry | Water–ice mix so the tube is surrounded by slurry, not frozen to the wall | Ammonia, lactate, many blood-gas transports when SOP requires cooling | A cup of ice cubes (focal freezing, hemolysis) or dry ice | | Refrigerated | Refrigerator temperature after collection or after spinning, as directed | Many separated specimens, some send-outs | Refrigerating whole-blood CBC overnight and expecting a valid differential | | Ambient | Room temperature, no ice | Many coagulation tubes (cold can activate platelets/factor VII); many routine chemistry tubes until processed | Icing a citrate PT "to keep it fresh" | | Frozen | Frozen aliquot after proper processing | Selected send-out analytes | Freezing the primary whole-blood tube, then thawing for a CBC |

Ammonia and lactate are the assistant-level ice-slurry pair: cells keep producing them at room temperature, so the specimen is chilled and usually separated promptly. Arterial blood gas (ABG) handling is SOP-specific: some protocols keep the syringe at ambient if analyzed immediately; others use ice for delay. CMLA does not ask you to freelance ABG science. Transport the labeled, de-bubbled, capped syringe the way the procedure says, and do not put it through a process the SOP forbids.

Do not ice everything "to be safe." Cold is a preanalytical variable.

Pneumatic tube exclusions

A pneumatic tube system (PTS) saves walking and can hemolyze specimens, leak containers, or delay irreplaceable samples in a stuck carrier. Follow the laboratory's exclusion list. Common teaching exclusions—confirm locally—include specimens that hemolyze easily or must stay ice-slurried without delay, some ABG syringes, some glass or large-volume containers, some irreplaceable or legal-evidence specimens, and leaking or unstoppered tubes.

If SOP says hand-carry, you walk. You do not "just this once" tube a neonatal bilirubin or a legal blood alcohol.

Accessioning, centrifugation, and aliquoting

Accessioning is logging the specimen into the laboratory information system: identity check, test codes, collection time, and comments (fistula arm, capillary, ice, light-protected). Flags for hemolysis, lipemia, or clots belong here when you see them.

Centrifugation happens after serum has fully clotted (commonly about 30 minutes; IFU wins) or promptly for properly mixed plasma tubes. Use closed, balanced buckets. Do not stop a spinning rotor with your hand, and do not centrifuge uncapped tubes. After spinning, many laboratories need plasma or serum off the cells within a defined time so cells do not consume glucose or leak potassium (the plasma-on-cells limit from Chapter 7). Gel barriers help; they do not excuse a hot courier car.

Aliquoting moves a portion into a secondary tube for analyzer racks or send-out. Use a pipette, not a pour across labels. Cap aliquots. Do not share one pipette across patients.

Send-outs to reference laboratories

Reference-lab transport is still your specimen. Package per SOP and courier rules:

• Primary container leak-tight and labeled.
• Absorbent material and a secondary leak-proof bag or container.
• Biohazard marking on the outer container as required.
• Test requisition outside the inner bag so paperwork is not soaked.
• A temperature monitor or cold pack / ambient pack / dry-ice shipper matching the directory (the monitor is how you prove the trip stayed in range).
• No unidentified tubes "for the reference lab to figure out."

Category A/B infectious-substance shipping (DOT/IATA) is a trained task. If you are not trained to classify a shipper, you do not improvise a dry-ice box.

In practice

You finish a draw for neonatal bilirubin, ammonia, a basic metabolic panel, and a send-out vitamin panel. You hold pressure, confirm the site is dry, and bandage. Bilirubin and vitamins go into light protection. Ammonia goes into ice slurry and is walked to the lab, not tubed. The metabolic panel goes ambient to accessioning. The vitamin send-out is aliquoted into a labeled amber tube after spinning, then bagged with absorbent, biohazard marking, and the catalog temperature pack plus a monitor.

Exam traps

• Elbow bending is not pressure.
• Ice slurry is not a cup of cubes and is not dry ice.
• Icing citrate is often wrong; icing ammonia is often required.
• Pneumatic tube is not a universal conveyor.
• Send-outs still need identifiers, biohazard packaging, and a temperature plan.

When CMLA names a specimen after the draw, answer with site care first, then light, temperature class, tube-versus-walk, and whether the next container is labeled before it receives blood.