Month: Jan 2021

DAT-Negative Hemolytic Anemias

drzeyd

This is a summary diagram for the causes of DAT-negative hemolytic anemia, both immune and non-immune. For immune cases, a negative DAT may indicate “not-detected” with the amount of immunoglobulin on the RBC being below the threshold of the test methodology being used. Also rare IgA associated cases will not be detected unless a specific alpha-heavy chain monospecific reagent is used.

New US CBER Guidance for Syphilis and Gonorrhea: December 2020

drzeyd

This is non-binding CBER guidance is a complicated algorithm that involves using treponemal and non-treponemal assays.  Re-entry pathway options are also provided.  I will be posting a summary and its implementation into my previous donor marker testing algorithms. Please see attached PDF link.

Click to access screening-tests-for-syphilis_december_2020.pdf

CBER Guidance Syphilis and Gonorrhea, December 2020

Opinion: Laboratory Software Issues from Hell

drzeyd

In my career, I have dealt with many different laboratory software vendors.  Regretfully, not all encounters have been straight-forward.  Since ultimately these products are used for patient care, I had hoped that there would be a sacred trust to do what is best.

Things that bother me:

  1. Current state:  whoever prepared it for the client, didn’t care or understand the local processes and came up with a generic:  Order it, collect it, receive it, do it, report it for each and every test.
  2. No training for super users:  more like lambs being led to the slaughter.  They will obey the vendor out of fear of making a mistake.
  3. No discussion of options:  pushing us to take the default setting—not even offering the available options.  The only way you find out there are available options is because other staff have used the same software at other institutions which used these options.
  4. Corrections to build:  only giving one shot to do it right, further corrections cost $$
  5. Scenarios:  vendor shows specially crafted scenarios that “work” but when you ask the vendor to do a random, non-scripted scenario, it crashes.
  6. Scalability:  limited scalability on client’s chosen platform.  That may force a rebuilding of the software when the limit is reached.
  7. Reference site does not match the test volume or activities of the client, uses different platform, and thus you cannot make a valid assessment.
  8. Performance issues:  if you don’t know why the system is slow, you can add more hardware (RAM, disk space, etc.) and try again—it can’t be due to the software design!
  9. Handling of requests:  does not permit your local IT staff to make changes, must send it back to the vendor for $$
  10. Waiting until hell freezes over:  will we get the corrected/updated package during this reincarnation?
  11. Interfaces:  an acceptable communication link is when one side speaks Sanskrit and the other Algonquin and they both hear each other, but who cares if they understand?
  12. Waiting for Godot:  God forbid if your equipment needs an interface not currently available:  how many cycles of the big bang can you wait?
  13. Champions or Heroes:  make a class of users who are to be evangelists for the new system and have them undergo sensitivity training including actions that are culturally irrelevant.  Don’t tailor it to local sensitivities or customs.  Will this convince the staff how useful the software is?
  14. Relevance of vendor experts:  Assume everyone understands what maple syrup is or comes from Kansas.  The expert assumes everyone has the same background as his/hers.  Who in the Middle East has seen maple syrup being made?  How can that analogy be useful for building software?
  15. Describe all reference units in feet/pounds/inches/furlongs/fortnights—no metric.  Do not use SI.
  16. Mix 24-hour clock with 12-hour clock:  what does 12:00 mean?  How do you measure time intervals?
  17. Consulting companies:  They are supposed to assist the client with the settings, but do they have the client’s best interests at heart?  Some are good spin-doctors and transfer blame to the client’s software staff when it is really their responsibility for the build.
  18. Rush, rush, rush:  Administrative powers who just want everything done quickly whether or not it is correct or validated properly, who cares if the processes built are right?

COVID-19 Convalescent Plasma CCP Donor Registration

drzeyd

I designed a completely quarantined process for collection, processing, and release of CCP at HMC Doha.  This document shows the Medinfo process for donor registration as a separate donor center code.

Check donor history and donor deferral database.  If there is no previous encounter, generate a new donor file:

At the completion of this action, the Blood Donation Record with the donor unit number (in this example 2200000099) and consent form in English and Arabic is generated.

CCP could only be collected at this special site and only the apheresis bag could be used for collection.  Regular donation options were not available at this CCP site nor was CCP collection an option at the regular donation sites.

8/1/21

Further Thoughts on Inter-Depot Transfer, Blood Delivery, Type and Antigen Matching

drzeyd

In my recent post, I provided sample flows and parameter mapping for delivery of blood components.  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.  In Medinfo, they can be added as a hospital blood bank site.

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-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).  With Medinfo, I can define rules (e.g. IgM titer < 1:64) to accept these units as a universal type for all ABO groups.

Special rules can be built into the software so that production, transfer, storage, and release of COVID convalescent plasma CCP are only performed at special quarantine sites by designated personnel.  This means there can be dedicated transport pathways built into the inter-depot transfer process to keep this inventory separate at all times.

Logistics and Processes for a COVID-19 Convalescent Plasma Program

drzeyd

I prepared the following plan for a CCP program for HMC Qatar in March, 2020.  The workflow is divided into four (4) modules:

  1. Registration/Interview/Physical Examination/Apheresis Collection
  2. Donor Marker Testing and Immunohematology Testing
  3. Production/Aliquoting/Pathogen-Inactivation/Storage
  4. Product Thawing/Product Release

Module 1:

  1. Collection/registration/screening must be in a separate area from regular blood and apheresis donations.
  2. Donors must provide consent.
  3. ISBT specimen labels must be used on each tube collected.
  4. We need a minimum of two apheresis nurses, one for the registration/screening/post-donation observation and one for the actual apheresis procedure.
  5. If there will be multiple serial donors, then we need a waiting area (each donor at least 2 meters apart).
  6. Donor screening must be in sound-proof area so that other waiting donors cannot hear the interview/questionnaire process.
  7. Amount that can be collected depends on body weight:  500 ml for <80 kg and 600 ml for >= 80 kg, collection may occur twice per week
  8. Collection time includes 15 minutes for registration/interview/physical examination, 60-75 minutes and 15 minutes for cleanup/disinfection before the next case, approximately 2 hours per donation.
  9. A post-donation observation area (minimum 15 minutes after collection) with apheresis nurse nearby in case of reactions is needed if there will be multiple donors.
  10. Specimens will

Module 2:

  1. Donor testing and donor immunohematology will be done with other donor specimens in our regular location

Module 3:

  1. Apheresis collection must be processed and stored separately from regular blood/apheresis donations.
  2. Processing will occur only after the results are shown to meet all criteria.
  3. Pre-collection testing (test-only donation) would permit processing without waiting for results.
  4. Storage at minus 80C may be for a minimum of six (6) years but this may be extended if needed.
  5. All acceptable components will have a final ISBT label—no products without the ISBT label will be transfused.  The ISBT label indicates that the unit meets all donor criteria for convalescent plasma.

Module 4:

  1. Product modification (thawing) and release (sign out from blood bank) must be in a separate area(s) from the regular hospital blood bank.
  2. Release of convalescent plasma follows the same process as regular component release
  3. Transfusion of convalescent plasma at the patient’s bedside follows same process as regular component transfusion
  4. Nursing and other staff performing the transfusion must pass competency assessment.
  5. Plasma will be transfused as ABO-identical or compatible unless low ABO-titer group A is used.
  6. Plasma must be free of clinically significant antibodies

Workflow Considerations:

  1. Donors must be restricted to the waiting, collection, or post-donation observation areas.
  2. Donors must NOT pass through production, testing, or component release areas (just as they are currently restricted in the Blood Donor Center and HMC hospital blood banks/transfusion services).

Logistics:

  1. Throughput is a maximum of 4 donors (2000 to 2400 ml plasma) per eight-hour shift with one apheresis nurse and one donor apheresis (Trima) machine.
  2. The processes are scalable with additional staff and machines (e.g. with 3 machines and nurses, then 12 donors and 6000 to 7200 ml of plasma collected).
  3. Thawing of 1-2 units of plasma takes up to one hour.  Contact the quarantine blood bank at least one hour before the desired pick-up time.
  4. The four modules above can be in separate areas not adjacent to one another.  Modules 1, 3, and 4 must be quarantine areas where access is limited.  Module 2 can be performed with regular donor specimens using standard precautions.
  5. We can provide training for transfusion of blood components and competency assessment to any location transfusing this product.

Information Technology:

  1. All modules will be connected to the Medinfo Hematos IIG dedicated blood bank computer system.
  2. All records of collection/production/testing/storage/modification/release will be stored therein.
  3. All ordering of convalescent plasma components will be through Medinfo.
  4. External test results (e.g. future antibody titering) can be added to the component information.
  5. Links to the Hospital Information System (Cerner) may be considered after the Medinfo processes are fully functional.

COVID-19 Convalescent Plasma CCP Site Registration

drzeyd

I designed a completely quarantined process for collection, processing, and release of CCP at HMC Doha.  This document shows the Medinfo process for site registration as a separate donor center code.

CCP could only be collected at this special site and only the apheresis bag could be used for collection.  Regular donation options were not available at this CCP site nor was CCP collection an option at the regular donation sites.

4/1/21

Therapeutic Apheresis Policy

drzeyd

This has been revised to recommend the use of a continuously recording portable vital signs device such as Umana’s UT1M (GPI, Italia) which includes PAO2 and heart rhythm measurements.

Principle:

All therapeutic apheresis procedures are potentially life-threatening and must only occur by an order from a transfusion medicine physician with experience/competence in such procedures.

Definitions:

  • Referring Physician is the clinical physician requesting a therapeutic apheresis procedure.
  • Transfusion Medicine Physician is a physician in the Transfusion Medicine Section with medical privileges for therapeutic apheresis procedures.  This includes the Head, Transfusion Medicine, consultants in Transfusion Medicine, and designated specialist physicians in Transfusion Medicine.  The final decision to accept/reject the patient is made by the transfusion medicine physician.
  • Covering Physician is the clinical physician designated by the referring physician to be physically present and covering the patient in case of any adverse reactions during a therapeutic apheresis procedure.
  • Apheresis Nurses are nurses in Transfusion Medicine who are designated by this section for performing therapeutic apheresis procedures.
  • Medical Privileges are determined by Transfusion Medicine in conjunction with the medical privileging by the Medical Director.

Policy:

  1. The referral physician will discuss the request for a therapeutic apheresis with the designated transfusion medicine physician.  The referral physician must certify that the patient can tolerate the procedure based on his medical condition.
  2. The transfusion medicine physician will review the patient’s clinical and laboratory data, with special note of the history of allergies, medications, previous transfusion reactions, and current vital signs.
  3. Vascular access will be initially assessed by the apheresis nurse.  Any questionable situations will be reviewed by the transfusion medicine physician.
  4. The following laboratory values (less than 24 hours old) must be available before the procedure may begin:
    1. CBC including platelet count
    2. PT and APTT
    3. Fibrinogen
    4. Serum calcium
    5. Serum protein and albumin
    6. LDH for TTP cases
  5. A valid type and screen must have been done within the previous three days of the procedure.
  6. Upon review of # 2 through 5, the transfusion medicine physician will determine if the procedure is indicated and will communicate this to the referral physician, who will sign written order in the patient chart.  Appropriate replacement fluids will also be mutually agreed upon in advance of the procedure and ordered by the transfusion medicine physician.  The order specification must include:
    1. Name of procedure and specification (e.g. therapeutic plasma exchange, isovolemic)
    2. Replacement fluid type and volume (e.g. 3 liters 5% albumin, 2 liters, FFP, cryoprecipitate, normal saline)
    3. Blood component orders if indicated (e.g. RBC exchange) and timing (before, during, and/or after the procedure)
    4. Calcium replacement (e.g. 2 grams calcium gluconate IV in 100 ml normal saline to run during the procedure)
    5. Any special laboratory testing post-procedure
  7. The apheresis nurse will follow the orders of the necessary prescribed replacement fluids (FFP, albumin, PPF) in the quantities necessary for the exchange.
  8. The referring physician will obtain the signed, informed consent from the patient.
  9. If vascular access is unsatisfactory, the referring physician will obtain the proper access (central line, AV shunt, etc.).
  10. The referring physician will arrange for a physician member of his team to be present at the actual therapeutic procedure.  This physician designate will be responsible to treat any complications arising from the procedure.
  11. Vital signs and weight will be obtained before starting the procedure.
  12. If the procedure is outside an intensive care unit and the patient is critically ill, consider the use of a portable attached monitoring patch (such as the Umana UT1M device).  The device will give alarm if any measurement is outside the defined ranges.
    1. If any blood components are administered, keep the patch attached to detect TRALI/TACO and other adverse transfusion reactions.
  13. When approved by the Blood Bank Director or designate with proper venous access and informed consent, the apheresis may start the procedure in the presence of the patient’s covering physician.  The procedure will be performed in a designated hospital area.
  14. The procedure must be documented on the appropriate therapeutic apheresis order and procedure worksheets.

References:

  1. Standards for Blood Banks and Transfusion Services Current Edition, AABB, Bethesda, MD, USA
  2. CAP Standard TRM.42245 regarding therapeutic apheresis procedures

Revised 3/1/21