Specimen Handling and Processing

Pre-Analytical Phase

• The pre-analytical phase consists of all steps taken before actual testing of the sample, and it is estimated that 46% to 68% of all laboratory errors occur during this phase.

Specimen Handling

• Routine handling of specimens involves mixing tubes by inversion (3-10 gentle inversions) and transporting them with the stopper up in plastic bags with a biohazard logo, liquid-tight closure, and a slip pocket for paperwork.
• Routine blood specimens should arrive at the lab within 45 minutes, and centrifugation should occur within 1 hour of arrival.

Special Handling Requirements

• Body temperature specimens should be collected in a pre-warmed tube and transported at or near normal body temperature (37°C) using portable heat blocks.
• Chilled specimens should be immersed in a slurry of crushed ice and water and tested immediately or refrigerated.
• Light-sensitive specimens should be wrapped in aluminum foil or placed in a light-blocking amber-colored container.

Specimen Processing

• In the central processing area, specimens are identified, logged/accessioned, sorted by department and type of processing required, and evaluated for suitability for testing.

Specimen Suitability

• Specimens are rejected due to hemolysis, insufficient amount, clotting, inadequate/inaccurate/missing ID, wrong/outdated tube, improper handling, wrong collection time, exposure to light, delay in testing, or delay/error in processing.

Centrifugation

• Centrifugation separates cells and plasma or serum using a centrifuge machine.
• Tubes awaiting centrifugation should have stoppers remaining on to prevent inaccurate results, evaporation, and contamination.
• Tubes must be balanced during centrifugation, and plasma specimens can be centrifuged without delay, while serum specimens must be completely clotted before centrifugation.

Stopper Removal

• Stopper removal may be done using devices or robotics, or manually with a face shield or splash shield, and gauze or tissue covering the stopper.
• Stoppers should be pulled straight up and off.

Aliquot Preparation

• An aliquot is a portion of the specimen used for testing, prepared by transferring a portion of the specimen into one or more tubes labeled with the same ID information as the specimen tube.
• Aliquots are used for multiple tests ordered, tests performed on different instruments or in different areas.

Non-Blood Specimen Labeling and Handling

• Non-blood specimens should be labeled with the same ID information as blood specimens, including type and/or source of specimen.
• Labeling should be applied to the container, not the lid.
• Familiarity with handling requirements is necessary to protect the integrity of the specimen and ensure accurate test results.
• All body substances are potentially infectious.

Urine Specimens

• Urine is the most frequently analyzed non-blood body fluid, readily available, easy to collect, and inexpensive to test.
• Urine analysis can aid in providing information on many of the body's major metabolic functions, monitoring wellness, diagnosing and treating urinary tract infections, and detecting and monitoring diseases.