after blood draw… specimenprocurement
TRANSCRIPT
After Blood Draw… Specimen Procurement
} Important to transportblood specimens carefully◦ Rough handling can hemolyze specimens and/or break
tubes} Blood specimen tubes are placed in plastic bags
for transportation to the lab◦ Bags must have a bio-hazard logo◦ a liquid-tight closure (in case of leakage)◦ slip pocket forpaperwork} Non-blood specimens should be transported in leak-
proof containers with secured lids, also placed in bagsas above
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} Guidelines (CLSI) set a maximum time limitfor separating serum and plasma from cells at 2 hours from time of collection (less time for some tests such as potassium)
} Prompt delivery & separation minimizesthe effects of cellular metabolism andglycolysis
} After collection, blood is exposed to the effectsof light, temperature and time.
} These can adversely affect some analytes inthe blood.
} Special handling is required for some teststo maintain integrity of the specimen.
� Keeping at Body Temperature� Chilled� Protect from Light� Processed in timely manner
Body Temperature
Some specimens will precipitate or agglutinate if cooledbelow body temperature (37°C)◦Examples: Blood for cold agglutinin,cryofibrinogen, cryoglobulins,and Semen sample
• Need to transport as close to body temp as possible
• Can use portable heat blocks, heel warmer, warm water
Chilled Specimens} Metabolic processes continue after blood has
been collected and can greatly affect someanalytes
} Chilling specimens slows down these metabolic processes and protects some analytes◦ ACTH, Lactic Acid, Blood gases, Renin, ACE,
Ammonia, Pyruvate, and PTH Related Peptide} Specimen must be completely immersed in a
slurry of crushed ice and water◦ Cubed ice does not allow adequate cooling} Some analytes are negatively affected by
cooling, ensure proper handling for test ordered 63
Protect from LightSome analytes are broken down bylight resulting in falsely decreased values
◦Ways to protect specimen:◦wrapping tube in aluminum foil◦using light blocking secondary containers◦Collecting in amber colored containers (microcollection and urine ones available)
◦i.e. Bilirubin – can decrease by 50% after 1 hr of lightexposureOther examples: Porphyrins –Beta carotene-Vitamin A –B-C-E containing specimens
Special Handling: Time-SensitiveCollections
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Legal and Forensic Specimens
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• Forensic specimens are those that may be used in legal proceedings such as alcohol and drug testing, DNA analysis, or paternity testing.
• A COC(Chain of Custody) is the legal paper trail that maintains the integrity of the specimen from time ofcollection through the testing process.
Legal Alcohol Collection
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• The site must not be cleaned with alcoholof any kind. Use a nonalcoholic antiseptic such as povidone iodine or chlorhexidine, or just soap and water.
• Fill the tube to minimize escape ofalcohol into the deadspace.
• Keep specimen capped until testing to prevent alcohol loss.
• Note: Tincture of iodine has alcohol in it
} Specimen is loggedas “received” once it arrives in the lab.
} Assigned a unique number (accession or sample number)used to:
◦Unmistakably connect specimento patient and orders, and◦to identify the specimen throughout all laboratory processes.
◦ Check are tubes received appropriate for tests requested◦ Correct tube for tests ordered?◦ Adequate volume?◦ Transported under correct conditions? (e.g. Temp)◦ May need to ask for new specimen◦ Labs usually have a specimen rejection policy
} Match the information on tube labels to info on requisitions◦ Unlabelled, mislabelled tubes are not acceptable
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} consider urgency, timedependency, irreplaceability ofspecimen
} knowledge of handling procedures & storage conditions for all specimen types◦ blood◦ urine◦ CSF◦ semen◦ synovial fluid◦ amniotic fluid◦ pericardial fluid◦ peritoneal fluid◦ pleural fluid
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} requisition time-stamped for tracking purposes
} prioritize◦ stat (urgent)◦ routine◦ special handling� time requirements: microscopic urinalysis
(fresh)� temp. requirements: refrigerated centrifuge
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} Enter patient andtest information into LIS
} LIS generates bar-coded labels for primary (source) container and aliquottubes
} Order correct tests (hasConsequences if incorrect)
} Verify any additional infois entered
◦ Eg. Height & weight for creatinine clearance test
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} varies with LISbut generally includes◦ accession number:
unique specimen identifier◦patient ID orhospital #: unique pt.identifier◦patient birthdate, age & sex◦ location: ward orclinic◦ tube type: eg. red top◦ tests required (test
codes)
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} info on requisitions or lab reports not discussed outside scope of assigned work
} don’t discuss in public places (elevators)} log out of computer systems-protect
passwords} verify identity of people requesting health
information
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} verify patient information, accession no. on label and onthe container match
} don’t obscureexisting containerlabels
} select correct no.and type of aliquot tubes for requestedtest
} barcode must be placed perpendicular to the tube in ordertobe read byautomated instruments
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} Most commonly done is separation◦ removing serum/plasma from cells
� Done through centrifugation
} Aliquot preparation – portion of sample isused for testing◦ Good when multiple tests on different analyzers
or in different labareas need to be run on one sample
◦ Pipette portion of sample into tubes that are labeled with aliquot labels (containing the same identification information as original sample)
} dispatch specimens to appropriate area for further processing oranalysis
} tests performed on plasma/serum require centrifugation
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} Stat requests go directly to testing area} For storage: use correct temperature◦ Room temp, fridge, freezer (-20 or -70)
} Packing for shipment to reference lab◦ Use correct materials◦ Consider storage temp: e.g. Dry ice◦ Follow regulations (TDG)� Classified as an infectious or a diagnostic specimen� Dry ice is classified as hazardous substance – must be
indicated on thelabel
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} add-on tests} test cancellations} upgrading urgency} results validation
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} Safety is paramount} Hazards◦ Aerosols from openingstoppers◦ Splashing when aliquoting◦ Cuts from brokenglass◦ Specimens arrive with needle attached (needlestick
Injuries)
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} Centrifuge mustbe balanced
} Bucket lids must be securely fastened
} Follow correct speed& time settings
} Must come to a complete stop before opening
} Carefully remove tubes,Checking for damage
} Tube breakage: cleanwith 10% bleach
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} Open tubes &pipette behind a splash shield or in a fume hood
} Verify 2 identifiers of the source container and aliquot container before transferring
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} When samples are ready they are sent for analysis
Questions