CLS 306 (BB) - Lecture 7: Pretransfusion Testing

1. LOW H&H result

2. Anemic to point of transfusion

3. Staff must initiate on behalf of patient

What is assumed leading up to compatibility testing (3)

Improve pt. blood oxygen-carrying capacity

Why Transfuse?

1. Decreased temperature

2. Decreased CO2

3. Decreased 2,3 DPG

4. Increased pH

Characteristics of blood with left shift on hemoglobin-oxygen dissociation curve (4)

1. Increased temperature

2. Increased CO2

3. Increased 2,3 DPG

4. Decreased pH

Characteristics of blood with right shift on hemoglobin-oxygen dissociation curve (4)

• Specimen collection and patient ID (phleb)

• Specimen ID verification (phleb/lab)

• Specimen meets requirements/age

• Review of patient records (BB)

Pre-serological procedures for compatibility testing (4)

• ABO/Rh typing and ABS of patient specimen

• AB ID when ABS positive

• ABO and Rh_o testing confirmation

• Crossmatch (random/screened) for transfusion

Serological testing procedure for compatibility (4)

• Proper release of test result (manual/electronic)

• Proper labeling of RBC

• Proper release/distribution

• Proper transportation/storage

• Proper re-release/distribution

Post-serologic procedure of compatibility testing (5)

ALL blood / blood components EXCEPT FFP or platelets

What blood components are typed and crossmatched

• Non-hemolyzed

• Free from IV contaminants

• Under 3 days old

• Keep for one week past transfusion date

Specimen criteria of patient blood(4)

• Non hemolyzed

• Pigtail / segment hermetically sealed + attached

• Always keep 2 PIGTAILS one week after transfusion date.

Specimen criteria of donor blood (3)

1. Check BB patient history file - If they tested for a clinically significant antibody, give them antigen (-) blood

2. Perform ABO and RH typing

3. Perform Ab screen

4. Perform crossmatch (Xmat)

What do you do for every patient tested ? (4)

All Rh neg RBC / WB units

Where is Rho(D) confirmation required on?

• Attached pigtail (never loose)

• Forward

• Rh neg

For ABO confirmation on a donor unit, you only test blood using the (——) on the blood bag and only (——) ABO typing is used for retyping all donor units. For Rh confirmation, only test (——) type donors at IS (Du not needed)

• Automated (Gel or solid phase)

• Manual (test tube)

Types of testing procedures done for ABS

• serological test using test tubes

• IS, 37, AHG

• Same potentiating media as ABS (LISS, PEG BSA)

Physical X-Mat (type of test, phases, reagents)

• Auto equipment (Gel / Solid Phase)

• Test phase can be different depending on equipment + media

Automated X Match (type of test, phases)

• Major: Donor cells + patient serum

• Minor: Donor serum + patient cells

In xmat, major crossmatching uses (——) samples while minor crossmatching uses (——) samples

• Final check of ABO compatibility between donor and patient

• Detects clinically significant antibodies

Two Main Functions of Cross Matching (2)

Immediate Spin

Most ABO incompatibility is shown at this test phase; potent other blood group IgM

• 2 drop pt serum + 1 drop donor RBC + LISS

• Incubate 37°C for 10-15 min

• 3 washes and centrifuge

• No agglutination = compatible

• Agglutination = incompatible

TT xmat procedure (5)

• 37°C

• AHG

Rh antibodies typically react at (——) while other blood groups react at (——)

1. Adequate washing

2. AHG reagent was added

3. Reagent is working

Check cells ensure that… (3)

• verify donor cell compatibility

• Detect MOST antibodies against donor cells

Pros of Serological Testing (2)

• Not guarantee healthy RBCs

• Prevent immunization

• Detect ALL antibodies

• Prevent DTR

• Detect all ABO errors

• Detect most Rh errors

Cons of Serological Testing (6)

• Current ABS is negative

• No history of antibodies

• 2 ABOs, 2Rh, and 2 ABS performed on 2 different specimens collected at 2 different times

Electronic X-Match Requirements (3)

ABS and Xmat performed simultaneously since usually patients are negative for ABS and thus Xmat will also be compatible to RBC units

What is done to improve TAT?

X mat unit or blood component

One transfusion record form (TRF) is printed and tagged per every (——)

CLS check each Xmat unit again

Prior to release/distribution of xmat unit, what must happen?

1. Ensure correct packing

2. Place temp control media to meet proper requirements

3. Lid affixed and CLOSED

4. Transport container displays patient’s name and MRN

Steps to ensure proper release/distribution of Xmat unit with a transport container (4)

Returned units were maintained at acceptable temperature limits

Re-release/Re-distribution of RBCs and blood components requires: