[17] CHAPTER VIII LESSON 1 Flashcards
can be defined as the use of serologic principles and tests to ensure compatibility and prevent an immune-mediated hemolytic transfusion reaction.
Pretransfusion testing
defines blood components as pharmaceuticals because of the intent of their use to cure, mitigate, treat, or prevent disease.
Food and Drug Administration (FDA)
Under the auspices of the [?], the Centers for Medicare and Medicaid (CMS) have the authority to regulate pretransfusion testing.
Clinical Laboratory Improvement Amendments of 1988 (CLIA ’88)
Facilities providing blood components and laboratory services are subject to. [?] by either entity at any given time.
inspections
In addition to maintaining regulatory compliance, many facilities participate in quality driven programs to achieve [?].
accreditation
The [?], now known simply as AABB, is an accrediting organization whose goals include enhancing the quality and safety of services provided by blood banks and transfusion services.
American Association of Blood Banks
Adequate pretransfusion testing does not guarantee [?] in the recipient’s circulation, but strict adherence to all facets of pretransfusion testing and donor unit selection is imperative to ensure safe transfusion therapy.
normal survival of transfused red blood cells
STEPS IN PRETRANSFUSION TESTING
1. Request for[?]
2. Identification of [?] and blood specimen collected
3. Testing of transfusion recipient’s [?]
4. Donor [?]
5. Donor [?]
6. [?] (crossmatch)
7. Labeling of [?] with the recipient’s identifying information and issue.
transfusion
transfusion recipient
blood specimen
RBC unit testing
red blood cell unit selection
Compatibility testing
blood or blood components
Testing of transfusion recipient’s blood specimen:
a. Evaluation of specimen for testing [?]
b. [?]
c. [?] (Weak D testing is optional when testing the patient)
d. Screening for [?] to red cell antigens
e. [?] if unexpected antibodies are detected
f. Comparison of [?], and any discrepancies shall be investigated and appropriate action taken before a unit is issued for transfusion
suitability
ABO group
Rh type
unexpected antibodies
Antibody identification
current and previous test results
- Donor RBC unit testing:
a. ABO group confirmation and Rh type confirmation for [?]
Rh-negative RBC units
- Donor red blood cell unit selection:
a. Selection of components of ABO group and Rh type that are compatible with the transfusion recipient and with any [?]
unexpected allogeneic antibodies
- Compatibility testing (crossmatch):
a. Serologic
b. Computer or electronic
SPECIMEN COLLECTION
Clerical errors and [?] continue to occur and have potentially serious, clinical consequences.
ABO-incompatible transfusions
- greatest threat to safe transfusion therapy
Clerical error
Clerical error Examples:
-misidentification of the recipient when the [?] is drawn
-[?] during handling in the laboratory
-misidentification of the recipient when the [?] is given
blood sample
mix-up of samples
transfusion
Errors include
phlebotomy and testing errors, administration to the wrong recipient, or issuance of the wrong donor unit.
continue to be a significant risk necessitating system to prevent failures in patient identification, specimen labeling, and administration.
Transfusion errors
In order to prevent patient misidentification and administration failures, most institutions require patients to wear a [?] upon admission until discharge
facility-generated ID wristband
facility-generated ID wristband must contain two unique identifiers, typically the
patient’s first and last names and date of birth or medical record number
require two unique identifiers to identify patients and ensure that correct medicine and treatment are administered.
Joint Commission’s National Patient Safety Goals
Prior to specimen collection, the phlebotomist must confirm the [?] is accurate and contains all required information.
wristband information
Common practice includes asking the patient to state his or her[?], if they are coherent.
name and date of birth
Once collected, the specimen must be accurately [?] at the bedside.
labeled
Patient information on the [?] must be in complete agreement.
label, wristband, and request
Furthermore, specimen draw [?] and the collecting individual must be traceable back to the collection of the patient sample.
date and time
are acceptable for pretransfusion testing.
Anticoagulated or clotted specimens
are often preferred due to ease of handling.
Anticoagulated specimens
are ideal for preparing a uniform cell suspension for testing.
Red blood cells from an anticoagulated sample
may require additional washing steps to minimize interference in test interpretations.
Clotted red blood cells
is unacceptable, and the use of hemolyzed samples should be avoided.
Intravenous line (IV) contamination
Specimens should be collected from the arm [?] the IV catheter and never [?] it.
opposite
above
If venous access is limited and the specimen must be collected from the IV line, the [?]must be stopped and the line flushed.
infusion fluid
It is recommended that an amount of blood equal to[?] the dead space of the catheter be discarded.
three or more times
The date of the collection is considered day 0, and the specimen expires at [?].
midnight on day 3
For example, if a specimen was collected on a Monday (day 0), it may be used for transfusion on Tuesday (day 1), Wednesday (day 2), and [?].
Thursday (day 3) until 11:59 p.m
The [?] minimizes the risk of an adverse reaction due to an emerging alloantibody in a recipient that has been recently transfused.
3-day testing window
Pretransfusion specimens and donor unit segments are typically stored at [?] and must be retained in the event that additional testing is warranted.
2° to 8°C
The patient sample and a segment from the donor unit must be retained post-transfusion for at least [?].
7 days
are performed to prevent an immune-mediated hemolytic transfusion reaction.
Compatibility tests
Compatibility tests include: determining the recipient’s [?], screening for any [?], and [?] the donor unit with the recipient’s plasma.
ABO group and Rh type
unexpected antibodies
crossmatching
Current results such as ABO group and Rh type, detection of clinically significant antibodies, significant adverse events, and special transfusion requirements must be compared to historical records.
Review of Records
For patients with no historical records, many facilities have implemented an additional specimen draw for a blood type confirmation.
Review of Records
Any discrepancy between historical records and current test results must be resolved prior to transfusion.
Review of Records
ABO grouping, Rh typing, and screening for unexpected antibodies must be performed within 3 days prior to the scheduled transfusion except in the previously mentioned situations for which the pretransfusion testing window may be extended.
Recipient Testing
requires licensed reagents and can be performed using tubes, column-agglutination technology, or in microtiter plates used in solid-phase red cell adherence tests.
ABO grouping
Required reagents include anti-A and anti-B for detecting the antigens on the red blood cells and A1 and B cells for confirming the naturally occurring antibodies in the plasma.
ABO grouping
is performed to detect the presence or absence of the D antigen.
Rh Typing
Licensed anti-D reagents are monoclonal blends of IgM and IgG components.
Rh Typing
In addition, an Rh control must be tested in parallel with anti-D reagent in the indirect antiglobulin test for weak D determination.
Rh Typing
The test for weak D is optional in transfusion recipients but is required for donor units during manufacturing.
Rh typing
Antibodies to blood group antigens must be detected and their clinical significance assessed.
Antibody Screening
Clinically significant antibodies have been associated with red blood cell destruction, hemolytic transfusion reactions, and hemolytic disease of the fetus and newborn (HDFN).
Antibody Screening
The FDA mandates that red blood cells used in antibody detection tests must express the following antigens:
D, C, E, c, e, K, k, Fya, Fyb, Jka, Jkb, Lea, Leb, P1, M, N, S, and s.
A common goal shared by blood suppliers and transfusion services is to provide a safe and efficacious blood component that benefits the intended recipient.
SELECTION OF DONOR UNITS
Blood suppliers are required to perform a battery of tests on blood components prior to distribution
Donor Unit Testing
Tests performed are ABO grouping, Rh typing, a weak D test if the initial Rh typing result is negative, and a screen for antibodies to common blood group antigens.
Donor Unit Testing
Required infectious disease testing on donor units includes HBV DNA, HBsAG, HBc antibodies, HCV antibodies, HCV RNA, HIV1/2 antibodies, HIV-1 RNA, HTLV I/II antibodies, WNV RNA, and a serologic test for syphilis.
Donor Unit Testing
In addition, each donor must be tested at least once for antibodies to Trypanosoma cruzi
Donor Unit Testing
Recently, the FDA provided guidance and recommended universal testing for the Zika virus.
Donor Unit Testing
- Selection Criteria
ABO antigens on the donor unit red blood cells must be compatible with the naturally occurring anti-A and/or anti-B in the recipient’s plasma.
ABO/Rh
If whole blood is the only option, the product and the recipient must be ABO identical due to the plasma portion of the blood component.
ABO/Rh
If a patient has a history of, or has detectable clinically significant antibodies, donor units selected for transfusion must be negative for the corresponding antigen(s).
Antigen-Negative
AB
1st Choice:
2nd Choice:
3rd Choice:
4th Choice:
AB
A
B
O
A
1st Choice:
2nd Choice:
A
O
B
1st Choice:
2nd Choice:
B
O
O
1st Choice:
O
No compatibility testing is required for the transfusion of platelets, thawed plasma, and cryoprecipitate.
Platelets, Thawed Plasma, and Cryoprecipitate
Either a current or a historical ABO grouping is sufficient.
Platelets, Thawed Plasma, and Cryoprecipitate
Rh typing is ignored because these components contain very few red blood cells as a result of collection methods or frozen storage.
Platelets, Thawed Plasma, and Cryoprecipitate
ABO-identical platelet units should be selected whenever possible to ensure adequate platelet survival.
Platelets, Thawed Plasma, and Cryoprecipitate
Plasma units should be compatible with the recipient’s ABO red blood cell antigens.
Platelets, Thawed Plasma, and Cryoprecipitate
