Now and Future Trends in

Blood Banking

Ricky Martinez Jr., RMT, BB (ASCP) SBB

AABB Standards

• This presentation is based on the experiences following the AABB

standards.

Pre Transfusion Testing• Physician’s Order Scheme:

• 1. Type and Hold

• a. ABO / Rh

• b. Hold the specimen for 3 days

• 2. Type and Screen

• a. ABO / Rh

• b. Antibody screen

• c. Hold the specimen for 3 days

• 3. Type and Crossmatch

• a. ABO / Rh

• b. Antibody Screen

• c. If negative – proceed to crossmatch

• d. If positive – perform antibody identification

• Once identified – select antigen negative blood only for the clinically significant antibodies detected

• If the antibody identified is classified as clinically insignificant – crossmatch

Pre Transfusion Testing

• The crossmatch (XM) is an important part of routine pretransfusion

testing.

• It is used to detect ABO incompatibility and other clinically significant

antibodies.

• Originally, the XM was intended to be a final check for ABO

compatibility and for the detection of unexpected antibodies.

3 Day Specimen

• The patients specimen is valid for 3 days

• Rule of thumb

• Day of specimen draw - day 0

• Next day – day 1

• Day after – day 2

• Last day – day 3 till 11:59Pm

• Note : No need to draw new specimen as long as the specimen falls within the 3

day period.

Type and Screen

• In preparation for an impending transfusion – patient specimen is tested

for an ABO / Rh typing

• Antibody Screen – is part of the pre transfusion testing scheme.

• Specimen is stored for 3 days.

• If the CBC results mandated for a blood transfusion – the specimen is

readily available for crossmatch.

Type and Cross

• Type and Cross

• The patient’s specimen is tested:

• ABO/Rh

• Antibody Screen

• Crossmatch

Evolution of the Crossmatch

• The XM has been modified many times

• In recent years the crossmatch has been abbreviated.

• The common types of XM currently being done are:

• 1. The immediate spin XM for antibody-negative patients

• 2. The antiglobulin XM for antibody-positive patients

• 3. The antiglobulin XM using the gel / column agglutination technique

• 4. The antiglobulin XM using the solid phase method

• 5. Computer assisted crossmatch. (EXM)

Negative Antibody Screen

• If the patient do not have any history of antibody on file

• And the current antibody screen is negative

• The crossmatch can be abbreviated

• Perform an IS (Immediate Spin Crossmatch) to detect an ABO incompatibility

• There is no need to carry the crossmatch to the coombs (AHG) phase

• You can completely avoid serological testing – by using electronic crossmatch.

Negative Antibody Screen

• If the patient has a history of insignificant antibody on file

• And the current antibody screen is negative

• The crossmatch can be abbreviated

• Perform an IS (Immediate Spin Crossmatch) to detect an ABO incompatibility

• There is no need to carry the crossmatch to the coombs (AHG) phase

• You can completely avoid serological testing – by using electronic crossmatch.

Positive Antibody Screen – Clinically

Insignificant Antibody Detected

• If the antibody screen is positive

• The antibody identified is classified as clinically insignificant

• 1. Perform crossmatch - crossmatch to AHG phase

• 2. Providing antigen negative blood to the corresponding antibody is not

necessary

• 3. Electronic crossmatch is applicable.

Positive Antibody Screen

Clinically Significant Antibody Detected

If the antibody screen is positive

The antibody identified is classified as clinically significant

• 1. Perform crossmatch - full crossmatch – up till AHG Phase

• 2. Provide antigen negative blood to the corresponding clinically

significant antibody detected

• 3.Use of computer crossmatch is contraindicated.

Negative Antibody Screen with Historical

Clinically Significant Antibody

• If the antibody screen is negative

• There is a historical clinically antibody on file.

• 1. Perform crossmatch - full crossmatch – up till AHG Phase

• 2. Provide antigen negative blood to the corresponding clinically

significant antibody detected

• 3.Use of computer crossmatch is contraindicated.

Antibody Screen

History Present Ab Sc Method

None - Negative Negative IS XM - EXM

Insignificant

Antibody

Negative IS XM - EXM

Insignificant

Antibody

Positive AHG - Gel

EXM not Valid

Significant

Antibody

Negative AHG – Gel

EXM not Valid (provide antigen negative unit)

Significant

Antibody

Positive AHG –Gel

EXM not Valid (provide antigen negative unit)

Limitations of the Crossmatch Procedure

• Though the crossmatch was originally intended for the detection of unexpected

antibodies, it has its limitations.

• 1.It will not detect clinically significant antibody due to the dosage effect.

• 2. It will not detect incompatibility from patients with historical record of previous antibodies.

Electronic Crossmatch

• Electronic crossmatching was first introduced in the USA at the University

of Michigan Medical Center in 1992.

• University of Chicago Hospitals implemented the electronic crossmatch

during the same year.

Computer Crossmatch

• Also known as “electronic crossmatch,” this is a type of

major crossmatch done without the need for test tubes or contact between

donor red cells and patient serum.

• The blood bank computer system compares ABO and Rh types of the

donor and recipient for compatibility.

• Safety is ensured by computer controls in the transfusion laboratory.

Purpose of EXM

• To respond faster to requests for blood

• To cut wastage by reducing the amount of allocated and stock blood in the system

• To reduce laboratory workload.

Who is eligible?

• Patients with a valid XM sample in the laboratory

• Patients with no clinically significant antibodies

Who is not eligible?

• Patients who do not have a current sample in the laboratory

• Patients with clinically significant antibodies.

• Bone marrow and stem cell transplant patients.

• Neonates of <4 months are not included as they are issued with O negative

pediatric units.

World Wide Use of EXM

• Computer crossmatching is used by many institutions in various countries-

North American facilities, Scandinavia, Hong Kong, and Australia.

• Some provide blood at remote sites lacking laboratory services.

Implementation of Electronic Crossmatching

1. Follow the current guidelines

2. Observe the regulatory requirements

3. Use recommendations that may prove useful for the implementation of

electronic crossmatching.

Requirements for EXM

• 1. Computer software

• 2. Dedicated MT with IT expertise

• 3. SOP for an electronic crossmatch

• 4. Validation – may take years

• 5. Full integration of the LIS to the BB computer system

• 6. Training of staff

• 7. Competence of staff

Integration of Laboratory Information Systems

• With the integration of laboratory information systems into transfusion

services, it is now possible to develop standard operating procedures

(SOPs) for an electronic crossmatch (EXM) to replace the immediate-

spin crossmatch for detecting ABO incompatibility between the blood

sample submitted for pre-transfusion testing and the donor unit selected

for transfusion.

Requirements for the Safety of EXM

• 1) The computer contains logic to prevent assignment and release of ABO

incompatible blood

• 2) No clinically significant antibodies are detected in the recipient's serum/plasma

• 3) There is no record of previous detection of such antibodies

• 4) There are concordant results of at least two determinations of the recipient's

ABO type on record, one of which is from a current sample

• 5) Critical elements of the system have been validated on-site

• 6) There are mechanisms to verify the correct entry of data prior to release of

blood.

Barriers in Electronic Crossmatch

• Time required for validation

• Validation must meet requirements.

• Training - electronic crossmatch will require additional time on the use of

blood bank information system.

• Software, not all laboratories have blood bank information system that can

perform electronic crossmatch.

Benefits of the EXM

• Despite those barriers the use of electronic crossmatch will likely increase

to cut cost and reduce turnaround time.

• Laboratories are facing staffing shortage due to both lack of graduates and

baby boomers start to retire.

• Implementation of electronic crossmatch can help blood bank reduce cost

and improve quality of service.

Summary - Electronic Crossmatch

• An electronic crossmatch is nothing more than using a computer to assign a unit of blood to a patient.

• The sole purpose of the electronic crossmatch is to confirm ABO compatibility between patient and donor.

• It cannot prevent hemolytic transfusion reactions caused by patient antibodies that are missed by the antibody screen

• It cannot prevent hemolytic reactions due to patient misidentification errors.

Trends in Transfusion Medicine

Trend to decrease testing by doing only those tests that will have a clinical impact.

1. Pretransfusion tests - to detect only clinically significant antibodies

2. Testing for weak D is eliminated for transfusion recipients.

3. Elutions on healthy newborns who have positive DAT due to antibodies in the

ABO system is not encouraged

4. Patients with historical clinically significant antibodies – perform abbreviated

identification by using selected cells only to rule out additional antibodies.

5. Methods for antibody screening that tend to detect cold antibodies have decreased

in use.

6.Wide use of immediate-spin phase during crossmatch.

Decreased Turn-Around Times

• Methods for pretransfusion testing that have a decreased incubation period and

thus a better turn-around time (TAT).

• Perform antibody screening methods using:(all of which have a 10-15 minute

incubation) PEG, LISS, GEL

• Streamlining encompasses using a maximum surgical blood order schedule

(MSBOS) to enhance efficiency of pretransfusion testing .

Transfusion Services

(wired, regionalize, centralize)

• Cost restraint and cut backs have motivated transfusion services to regionalize

and to centralize.

• A centralized transfusion service performs all routine and complex testing

• Centralized testing are also wired transfusion services, in which centralized

laboratories communicate with satellite labs via a shared laboratory information

system and intranet.

• Serological pretransfusion testing is done at the central lab and the satellite lab

performs electronic crossmatches on-site.

Blood Substitutes

• Needs

• 1. To maintain a constant supply of safe alternative

• 2. To overcome complex procedures of blood collection and processing

• Types

• 1. Hemopoietic Growth Factors & Pharmacological Agents

• 2. Real Blood Substitutes

Red Cell Substitutes

• Hemoglobin Based 1st Generation Purified, unmodified hemoglobin

Generation

• 1. Intramolecularly cross linked hemoglobin

• 2. Recombinant hemoglobin

• 3. Polymerized hemoglobin (or hemoglobin directly linked to a high

molecular weight non protein carrier)

• 4. 3rd Generation Artificial red blood cell (encapsulated hemoglobin)

Platelet Substitutes

• Platelet Substitutes - Platelet membrane preparation

• Freeze Dried Lyophilized Platelets

• Synthetic platelets

• Microspheres of human albumin coated with human fibrinogen.

New Technologies in Blood Banking

• 1. Molecular techniques blood group genotyping using allele specific

primers and PCRs for Duffy, Kell, Kidd, MN, ABO, Fetal RhD typing and

HLA typing

• 2. Gel Technology

• 3. Column Agglutination Technology

• 4. Erythrocytes Magnetized Technology

Blood Bank Information Systems

• Blood bank information systems are computer systems that have been

developed specifically to assist the blood bank professionals in

management of the patients, donor and blood component information.

• Helps to correlate the laboratory data with donor records and help to trace

the donor records following transfusion reactions.

Cord Blood Banking

Cord blood is defined as blood contained within umbilical cord & in the placental

circulation.

Procedure:

Umbilical cord is clamped & cut as in routine manner

Insertion site on the umbilical vein is prepared by cleaning with betadine &

alcohol.

Cord is preserved under controlled conditions.

In Vivo Crossmatch

• An in vivo crossmatch can be accomplished by measuring the change in

the recipient's serum bilirubin after transfusion of 50 ml. of blood from a

particular donor unit.

• A rise of less than 0.5 mg. per 100 ml. has been good evidence for

compatibility.

Blood Delivery -Drones

• Drones are enabling improved health care delivery by providing faster

response times, reduced transportation costs, and improved medical

products/services to remote and/or underserved environments.

References

• WHO Transfusion Medicine Technical Manual, 2nd Edition 2003

• Internet: - NACO Blood Bank (PDF Document)

• FDA Guidelines to Inspection of Blood Banks

• Voluntary Blood Donation Program: Operational Guide by NACO