1. Specimen Verification Requirements


Basics of Transfusion Science

  • Definition: Transfusion science is a branch of medicine focused on the safe and effective use of blood and blood components for patient care.

  • Also referred to as:

    • Blood Bank (BB)

    • Immunohematology

    • Transfusion Medicine (TM)

    • Transfusion Services

  • Key areas included in transfusion science:

    • Blood typing – ABO/Rh

    • Compatibility testing – transfusion of blood

    • Blood donations including testing for Transfusion-Transmissible Infections (TTI), component preparation, product storage

    • Management of transfusion reactions

Specimen Collection and Testing Requirements

  • Preferred Specimen: K2 EDTA

    • Both red cells and plasma/serum tested.

    • RBCs exhibit antigens on their membrane surface; plasma/serum contains antibodies.

  • **Specimen Handling: **

    • Serum can be used, red stoppered tubes acceptable.

    • Critical pre-analytical procedures must be followed to prevent errors.

Labeling and Traceability Protocols for Transfusion Specimens

Pre-analytical Procedures

  • The most dangerous pre-analytical error: wrong blood in tube.

    • Mandatory that patients are positively identified using at least two unique identifiers:

    • Full name

    • Unique hospital number

    • Date of birth (D.O.B.)

    • Patients should be asked to confirm their full name and D.O.B. when possible.

  • Specimen Labeling:

    • Must label specimens immediately at the bedside – pre-labeling is not allowed.

    • Labels applied before leaving the patient.

    • Unlabeled or mislabeled specimens must be rejected (no exceptions).

    • Preferred barcode labels must contain:

    • Patient’s full name

    • Unique ID number

    • D.O.B.

    • Date and time of collection

    • Phlebotomist initials or ID

    • Physician (optional)

Specimen Collection Considerations

  • Specimen must match strict criteria:

    • Request form must match specimen label must match patient wristband.

    • Document the phlebotomist who collected or tested samples for traceability.

    • Testing should occur within a 72-hour window to avoid missing complement dependent antibodies.

Traceability of Specimens

  • Definition of Traceability: Ability to track the specimen from its collection through to its final disposition.

  • Coverage of Traceability Must Include:

    • Patient → specimen → testing → blood component → transfusion outcome.

  • Traceability Document Requirements include:

    • Collection record

    • Transport log

    • Laboratory accession number

    • Testing worksheets or Laboratory Information System (LIS) records

    • Blood products transfused (including unique donation number, component type, ABO/Rh type, expiry date)

    • Compatibility test results.

    • Transfusion record and monitoring data.

Blood Product Traceability

  • In case of a transfusion-related adverse outcome, records must allow positive matching of the product to the patient.

  • Every unit must be traceable:

    • Look-back or traceback allowed by Canadian Blood Services from donor to product transfused.

    • Trace from donor through processing, storage to recipient or disposal.

Specimen Rejection Criteria

  • Specimen must be rejected if:

    • Patient identifiers are missing or incorrect.

    • Label does not match the request form.

    • Sample collected in the wrong tube.

    • Specimen is hemolyzed or contaminated.

    • Specimen collected outside the allowed time window (e.g. >72 hours for recently transfused patients).

Retention and Record Keeping

Specimens

  • Stored per policy, often for 7 days post-transfusion.

Blood Bank Records

  • Kept for 10 to 30 years depending on local regulations.

  • All records must be:

    • Legible

    • Secure

    • Auditable

Transfusion Records

  • Must retain records of release of blood components and products for transfusion including:

    • Recipient identification

    • Donation codes

    • Lot numbers of products for a minimum of 50 years.

Verification of Information and Sample Suitability

  • Before specimen acceptance:

    • Ensure all relevant info for testing requested is complete, accurate, and legible.

  • Relevant verification information includes:

    • Patient’s full name

    • Unique patient identification number

    • Date of birth (DOB)

    • Test(s) requested

    • Date and time of specimen collection

    • Phlebotomist or collector identification.

Assessing Specimen Suitability

  • Any discrepancy between specimen label and request form makes the sample unsuitable.

  • Confirm appropriate anticoagulant and specimen type.

  • Evaluate specimen volume and visual inspect for hemolysis or clotting (especially in EDTA samples).

  • Assess specimen age and stability, taking into consideration recent transfusions or pregnancies.

  • Document acceptance or rejection and determine course of action for preanalytical errors.

  • Follow established transfusion science protocols focused on patient safety and documentation.

Blood Bank Specific Checks

  • Account for recent transfusion or pregnancy history within the last three months.

  • Note special requirements (e.g., for antibody investigation, urgent transfusion).

Verification of Patient Information and History

  • Accurate patient identification is crucial for safe transfusions.

  • Patient history influences the interpretation of lab results.

  • Verification of patient records can identify:

    • Previous transfusions

    • Pregnancy history

    • Known antibodies

    • Previous ABO/Rh group results.

  • This information guides blood selection by influencing:

    • Identification of clinically significant antibodies

    • Special requirements like antigen-negative units or irradiated blood

    • History of transfusion reactions.

  • Failure to verify patient history can lead to hemolytic transfusion reactions (HTR).

Specimen Retention and Management

  • Specimens retained based on:

    • Test type

    • Clinical significance

    • Regulatory and institutional policies.

Storage Conditions:

  • Refrigerators (2–8 °C):

    • For short-term storage of blood specimens and components.

  • Freezers (–20 °C or –80 °C):

    • For long-term storage of plasma, serum, or reference samples.

    • Continuous temperature monitoring required (24/7).

  • Dry Ice:

    • Used for frozen specimens like frozen plasma.

    • Must use insulated containers with proper ventilation.

  • Liquid Nitrogen:

    • Utilized for long-term cryopreservation of rare RBCs and cord blood stem cells.

    • Essential for preserving frozen RBCs with unusual antigenic profiles to assist in antibody identification.

  • Disposal of Specimens:

    • Specimens must be treated as biomedical waste.

    • Decontamination processes, e.g., autoclaving, applied as needed.

    • Disposal managed by approved biohazard waste contractors.

    • Disposal procedures documented to maintain traceability and compliance.

Summary of Retention and Record Keeping

  • Specimens: Retained as per policy (often for 7 – 14 days post-transfusion or longer).

  • Blood Bank Records: Retained for 10 – 30 years, subject to regulations.

  • Transfusion Records: Documentation of blood product release, including:

    • Recipient ID

    • Donation codes

    • Product lot numbers must be preserved for at least 50 years.

Current Good Manufacturing Practice (CGMP)

  • CGMP principles require that all recorded data be:

    • Accurate

    • Complete

    • Legible

    • Traceable

  • Data errors must be corrected without erasing or deleting the original entry:

    • Original entry must remain legible with corrections clearly identified.

    • Each correction must state the reason for the change, date, and identity (initials/signature) of the person making the correction.

    • Corrections must adhere to approved Standard Operating Procedures (SOPs) and may require supervisory review for critical records.