Category: Blood Bank IT

Includes all areas: Donor, patient, marker testing, component preparation

Policy: Donor Reactions

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Document Enumeration:  5.6

Policy:

  1. All donors must be continuously observed throughout and after the collection process.
  2. Donors showing any signs of an adverse reaction must be treated promptly.
  3. All collection staff should be trained and deemed competent to handle donor reactions.
  4. All adverse effects should be recorded in the appropriate log AND the Hematos IIG system.
  5. All policies, processes, and procedures must comply with Qatari, HMC, and applicable accreditation standards (i.e. AABB, CAP, and JCI).

References:

  1. HMC 1001 Setting Specification, Version 1.5, Hematos IIG, Medinfo
  2. Standards for Blood Banks and Transfusion Services, Current Edition, AABB, Bethesda, Maryland, USA

Opinion: Selecting a Pathogen Inactivation System

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Transfusion-transmitted infectious disease are a continuing threat.  Despite donor infectious marker testing and new donor questioning, there are many threats which are not addressed by these measures.  Also new pathogens are being identified for which there are no tests or specific donor questions available.  How can we handle these new threats?

Pathogen inactivation can significantly reduce infectious agents in blood components, although the degree varies depends on the agent.  Theoretically any agent with nucleic acid—RNA or DNA is affected.  The only class of agents not affected at all are prions, which have NO nucleic acid at all.

In general, a photoactive agent is added to the blood component which binds to the nucleic acid.  Photoactive agents include riboflavin, psoralen dyes, and methylene blue.  Then the component is irradiated, the time proportional to the volume of the unit.

The component is then exposed to ultraviolet light to photoactivate it, which disrupts the DNA and RNA present, including in the white cells.  Thus, NO irradiation or bacterial culture is required.

Here are my questions to consider when selecting a pathogen inactivation system:

Targets?  Platelets vs plasma vs whole blood?

Methylene may be used for plasma, but riboflavin or psoralens may be used for platelets or plasma.  Whole blood inactivation with riboflavin is CE-approved.

Photoactive dye:  Is it riboflavin vs psoralen vs methylene based?

Riboflavin is vitamin B2—the amount used is small and does not need to be removed whereas the psoralen must be removed for clinical use.

Does the photoactive material need to be removed before transfusion?

You can immediately use the riboflavin-treated component but the psoralen must be removed before transfusion—this may take 6 or 20 hours depending on the licensing of the product.

What is the loss of platelets or coagulation factors after treatment?

With treatment by all methods, there is some loss of platelets and coagulation factors.  The platelet loss may be greater in psoralen-based methods and require additional components be added to the pool to reach the desired dose.  Likewise, plateletpheresis components treated with psoralen may require a recalibration of the donor apheresis equipment to collect more platelets per dose to compensate.  There may be some RBC loss additionally in whole blood pathogen inactivation.

What is the efficacy of pathogen reduction for the infectious agents, particularly the ones in your region?

Example:  How well does the treatment handle local agents like Hepatitis E?  Psoralen agents may be less effective than riboflavin for this agent.

Does it work with platelet additive solution PAS?

There are minimum and maximum volumes for pathogen inactivation set by the manufacturer.  Can you get sufficient yields within these volumes?

How good is the data management system?  Can it be integrated with your blood bank computer system?

Can the equipment be integrated with your system?  This is important to set rules and enforce good manufacturing processes GMP.

Does it work well with an automated blood component production system?

Such automated systems like the Reveos can free up personnel for pathogen inactivation.  Can the volumes produced be handled effectively by the pathogen-inactivation method?  Do the timings for separation of components work synergistically with the pathogen inactivation method?

Vendor issues:  how well will the local agent provide support?  Is someone else in your country or region using the system?

You need an experienced vendor to provide optimal support.

Allocation Antigen Matching in Medinfo

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In the previous post, the Medinfo document for Inter-Depot transfer had many pages of rules for matching RBC antigens.  Multiple actions were available:

  1. Forced Match, no release of untested or antigen-mismatch (e.g. anti-Kell requires specifically tested K-negative RBCs).
  2. Match Optional (e.g. anti-Lea/Leb does not require Lewis-matched blood):  system would flag a comment showing the antibody specificity, user would respond Y/N, and select units
  3. Least-Incompatible (e.g. WAIHA):  requires sufficient privilege (senior technical or transfusion physician) to authorize release
  4. Permitted Incompatible (e.g. give C-positive to patient with anti-C in times of shortage or complex multiple antibodies without fully matched blood available):  requires sufficient privilege to release
  5. Fully Allowed (e.g. group O RBCs to group A, AB, B patients)—no flagging, allocation of units permitted
  6. Prohibited Under Any Circumstance—NO Override Permitted (e.g. group O for Bombay Oh, c-positive for anti-c, K-positive for anti-K)

To avoid mistakes, the blood bank computer system enforced the rules.  There was no mercy.  Only specific individuals could override this( in many cases, but certain allocations (e.g. group O RBCs to a Bombay Oh patient) were not permitted under any circumstances.

Prophylactic Antigen Matching:

Please also refer to my prophylactic antigen matching post made last week for the rules I selected for Qatar.

Prophylactic antigen matching is common in Europe.  I have been doing this during the many years I have worked in the Middle East.  Most patients were not local nationals but transient.  They would return to their home countries where blood bank testing (antibody screening/identification/antigen matching) or intrauterine exchanges might not be always available.

For pregnant patients, we would prophylactically match K-negative and c-negative—regardless if there were antibodies detected—R1R1 units for R1R1 patients.  At the end of my time in Qatar, we had several pregnant women with various Rh deletions, so we added routine extended Rh(D) and Kell typing to all.

For sickle cell patients, especially African type, I would prophylactically match Rh antigens (D, C, c, E, e) and Kell because of the polymorphisms in the CE gene, some of which may lead to pan-Rh antibodies.

I would consider selective prophylactic antigen matching in chronically transfused populations, again regardless if clinically significant antibodies were detected.

If a patient makes any antibody, regardless if is clinically significant or not, I would consider that patient as a candidate for prophylactic antigen matching (but NOT necessarily for a clinically insignificant antibody).

In Qatar, blood bank services (testing and components) were not charged to the patient.  In many other parts of the world, blood bank is a cost center.  No prophylactic antigen matching may be routinely performed.  If it is done, it must be charged to the patient or the hospital must assume the cost.  I have gone to conferences in such locales where not even R1R1 patients were not matched and subsequently developed anti-c, which complicated management.  It would have been cheaper to do the antigen matching than to pay for the consequences of the alloimmunization.

Allocation Rules for Platelets and Plasma

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Medinfo Hematos IIG software is rules-based so the institution may set its own custom rules for all processes.  One chooses a framework and then adds any additional rules it needs for optimization.  Turnkey systems do not offer this flexibility.

The rules for platelet and plasma components are much simpler than those for RBCs since usually we only consider ABO type.  There are two modes:  regular and emergency, the latter applying if not all the patient testing (including historical checking) is available.  The components, on the other hand, must meet all criteria before being considered for patient use.

Please note that any donor with antibodies is automatically excluded from plasma and platelet production based on our donor testing criteria.

Example rules for plasma follow:

For platelets, note that for adults and anyone else >= 20 kg, I gave any type of platelet pool or plateletpheresis component without regard to ABO matching.  With our production method, I did not give Rh immunoprophylaxis to females of child-bearing age receiving platelets from D-positive donors based on our clean (essentially RBC-free) Reveos automated production process.

For platelets, there were also different allocation rules for regular and emergency mode:

Similarly, allocation rules for granulocytes, etc. can be made and enforced by the software.  Low-B-titer group A universal plasma would also be easy to implement.

Regular and Emergency Mode RBC Antigen Matching

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Note:  This is an update of a previous post.

In the previous posts I outlined how Medinfo handled antibody screening and identification.  This post reviews how antigen matching is used based on these results.

There are two modes, regular and emergency.  If the patient has not had at least two ABO/D determinations and/or does not have a recent antibody screen within the past 3 days, then emergency mode must be selected with its own rules.  Otherwise, the regular mode applies.

Regular Mode:

In general, if there is a clinically significant antibody, an RBC unit which has not been matched for the corresponding antigen or has the corresponding antigen cannot be routinely selected.  However there is a hierarchy here also:

  1. Absolutely prohibited release—no one can override the logic (e.g. giving group O to a patient with anti-H)—not even the transfusion medicine physician can override this
  2. Restricted release—only transfusion medicine physician can authorize the release of the incompatible or untested unit (e.g. giving C-positive unit to someone with anti-C)
  3. Least-incompatible for warm autoimmune hemolytic anemia WAIHA:  requires transfusion medicine physician approval
  4. Informational release:  authorized staff may release antigen-incompatible or untested unit but a pop-up menu appears and asks them to accept (e.g. Lewis untested unit in a patient with anti-Lea).
  5. Antigen-specificity matched—the usual mode for patients with antibodies

Examples of Regular Mode rules follow (these are not the complete lists but just provided to show the complexity of the process).


Emergency Mode:

This is much more restricted for selection of ABO/D and other antigen typings.  An example follows:

If low-titer group O whole blood is available, then a specific rule must be added to both regular and emergency mode to allow this to be given to any ABO type except Bombay.

Inter-Depot Transfer, Blood Delivery, Type and Antigen Matching

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This is an update of a previous post.

The final components from the component preparation center may be sent to various depots (freestanding location and/or hospital blood banks.  There should be complete traceability for every step (from donor reception, collection, testing, and processing) transport between locations, and finally the exact storage site, which might include which refrigerator/freezer/incubator and even shelf/position number for each component is stored.  The end of that document showed rules for type/antigen matching.

For disaster planning, rapid inventory enumeration by type is very important.  This can be very time-consuming manually.  With our Medinfo Hematos blood bank system, we could quickly get total inventory across the Qatar or by hospital in less than one minute.  We could also quickly find antigen-matched units across the system and reserve it at any one site for another if necessary.

Smart blood bank dispensing refrigerators, as offered by Haemonetics and Angelatoni, may also serve as depots and take the place of a hospital blood bank for some dispensing.  These solutions can also capture vital information about the storage conditions of the components and prevent release if the storage criteria are not met.  They can also interface with blood bank computer systems and use the main system’s logic for the dispensation rules.

Upon receipt at the hospitals from the blood processing center, the forward ABO and D typing must be confirmed.  We used D reagents which detected partial D so we would call such donor units as D-positive.  However, if a patient type reagent insensitive to partial D types is used, it is possible for a unit to be typed as D-negative whereas in the donor center it might be D-positive.  Sometimes, nothing types consistently as D-positive:  all you can say is that with a particular reagent and lot number, there is or isn’t reactivity.

The greatest complexity is for RBCs since potentially so many antigens exist.  Criteria for matching/ignoring certain antigens must be made.  Critically significant antibodies such as the Kell, Duffy, Kidd, and certain Rh (D and c) must be antigen matched.  A robust blood bank computer system can enforce these rules.

For other components, antigen/typing may be less important.  In fact, in most situations, any type of platelets can be given to anyone (except neonates).  Despite the potentially incompatible plasma, there is rarely significant hemolysis.  In fact, if pooling platelets without regard to blood types is done, a platelet transfusion is a common cause of a positive direct antiglobulin test DAT—something that is not clinically significant.  No one died of a positive DAT by itself for this reason.

Specific rules for compatible plasma types are important, but nowadays, low-anti-B-titer group A plasma may be used like universal AB plasma.  The challenge is to be able to perform the ABO titration (specifically anti-B) quickly—titration can be a slow process, even with automated equipment.  A similar situation for low-titer, universal group O whole blood requires both anti-A and anti-B titration (I will return to this topic in a future post).

Process: Donor Collection

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Process:  Donor Collection

Zeyd Merenkov, MD, FCAP, FASCP

Independent Consultant in Transfusion Medicine

5.4.1 PROCESS DONOR COLLECTION:

Process:

  1. Donors must pass and complete all previous processes in the donor workflow (registration, questionnaire, and physical examination) before the collection process begins.
  2. The donor is positively identified by a designated picture ID and Hematos donor consent form with specimen/encounter number and barcode.
  3. Donor staff checks and prepares a suitable vein
  4. Donor staff collects/labels specimens and the whole blood or apheresis components AT THE DONOR’S BEDSIDE.
  5. Donor reactions are assessed and treated as they occur.
  6. Donors are observed in a post-donation area and given post-donation instructions before discharge.
  7. All processes are documented in Hematos IIG.
  8. Donor units and specimens are sent to component processing and donor marker testing.
  9. The collection workstation and equipment are cleaned before starting a new donor collection.

References:

  1. HMC 1001 Setting Specification, Version 1.5, Hematos IIG, Medinfo
  2. Standards for Blood Banks and Transfusion Services, Current Edition, AABB, Bethesda, Maryland, USA