major crossmatch versus typescreen

7/30/2019 Major Crossmatch Versus TypeScreen

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Major Crossmatch versusType&Screen : Why to choose for

Type&Screen

Major Vandenvelde Christian, PhysicianBiologist, Head of Military Service for

Blood Transfusion, Head of BrugmannU.H.C. / Queen Fabiola Children U.H.C. /C.T.R. / Heysel R.C. Immuno -

Haematology Laboratory


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What is a Major Crossmatch ?

Compatible RBC Bag(s) request

Patient RBC ABO-D(-CcEe)(-K) Typing

Typing-compatible RBC Bag(s) selection

Bag(s) RBC crossmatching with Patient plasma

Bag(s) RBC compatible with Patient plasma

RBC Bag(s) reservation for Patient

What if positive Major Crossmatch ?


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What is a Type&Screen ?

Compatible RBC Bag(s) request

Patient RBC ABO-D(-CcEe)(-K) Typing+ Patient plasma Screening for Irregular

anti-RBC Ab by crossmatching withcommercially available selected 3-RBC-panel(s)

Patient plasma negative IAT Typing-compatible RBC Bag(s) selectionwhen needed

What if positive IAT ?


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What if positive MXM / IAT ?

Positive MXM Either : further Bag(s) RBC Crossmatching with

Patient plasma

Or : Patient plasma Screening for Irregular anti-

RBC Ab Positive IAT

Irregular anti-RBC Ab Identification withcommercially available 11-RBC-panel(s)

Typing- & Identification-compatible RBC Bag(s)selection when needed

What if available Bag(s) RBC were not phenotyped forconcerned Ag ?

What if Patient anti-RBC Ab remain(s) unidentified ?


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What if unidentified Patient Ab /

non-phenotyped Bag(s) RBC Ag ?

Available Typing-compatible Bags RBCCrossmatching with Patient plasma

Available Typing-compatible Bags RBC

phenotyping for concerned AgTyping- / Identification-compatible RBC

Bag(s) searching by B.T.C. in :

national BTI RBC Bags stocks international BTI Frozen-Phenotyped-RBC

Bags stocks


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PRELIMINARY CONCLUSION

Most of the time the right question will be :Why to choose either for MXM or for T&S asFIRST RBC compatibility test ?

4 Ways to go :

MXM only Example : Q.A.M.H. Blood Bank

T&S only Example : Military Ops Support

First T&S, then MXM Example : BrugmannU.H.C. (Laeken + Schaerbeek + Jette sites) / Queen

Fabiola Children U.H.C. / Centre for Traumatology& Rehabilitation / Heysel Rehabilitation CentreBlood Bank

First MXM, then T&S Example(s) : cfr previous

presentation


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Type&Screen resources constraints

Reagents : commercially available ScreeningRBC-panels are expensive but

Technologists : Screening procedures are easyto automate but

Equipments : Screening automates areexpensive but

RBC Bags stock : Screening allows

an average RBC Bags stock reduction of +/- 33% an average RBC Bags expiry rate reduction of +/-

95%, especially when a M.S.B.O.S. has beensuccessfully implemented, but


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Type&Screen Patient risks

Screening misses 1 allo-Ab per 3000 RBCcompatibility tests but

Screening misses 1 weakly-reactive potentiallyclinically significant allo-Ab per 30000 RBCcompatibility tests but

Screening-missed allo-Ab likely would not result inlife-threatening reactions but

Screening misses clerical ABO-compatibility RBCBags selection / labelling errors but

Screening is mandatory followed by an ABO-compatibility check but

Screening misses allo-Ab present in residual plasmaof RBC Bags but

National BTIs have to warrant the absence of

clinically significant allo-Ab in produced L.B.C.


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MXM only : Burn Unit Q.A.M.H.

Blood Bank support

Reagents & Equipments : no de novo allo-Ab in 13 years

3 allo-Ab at admission in 13 years

+/- 66% of requested RBC Bags are transfused

Technologists : no experience in allo-Ab identification

1 MXM for 2 RBC Bags from same apheresis donor

presence required for other lab tasks

RBC Bags stock : 2 times the average numberof transfused RBC Bags

Patients risks : ABO-D-CcEe-Kk-compatibleRBC Bags are electronically selected


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T&S only : Military Ops Q.A.M.H.

Blood Bank support

Reagents, Technologists & Equipments : Screening before departure makes field-lab

compatibility testing useless

Screening-positive soldiers remain in Belgium(0.01%)

RBC Bags stock : 20 refrigerated + 1200frozen O Rh/K-negative RBC Bags arecontinuously available

Patients risks : O Rh/K-negative RBC Bags are universal

RBC Bags are systematically tested for auto- & allo-Ab

Donor Typing occurs at least 2 times before first

donation


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First T&S, then MXM : Brugmann

Blood Bank resources constraints

Reagents : unusually high frequency of allo-immunised, polytransfused & multipregnancypatients

Technologists : important experience in allo-Ab identification 4 years ago, 15% of requested RBC Bags were

transfused

Equipments : 4 years ago, unusually high

frequency of RBC Bags requestsRBC Bags stock : after 4 years, RBC Bags

needs & expiry rates have already beenreduced by 33% & 85%, respectively


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First T&S, then MXM : Brugmann

Blood Bank risks management

Extended phenotyping of haematology /oncology patients at first admission

As extended as possible electronic-crossmatch

for haematology / oncology / childbearingpatients

Maximal use of ABO-D-CcEe-Kk-DAT-IATscreened RBC Bags

Maximal availability of extendedly phenotypedRBC Bags

ABO-compatibility check at patients bed


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FINAL CONCLUSION

QUESTION :Why to choose either for Major

Crossmatch or for Type & Screen as

(FIRST) RBC compatibility test ?

ANSWER :

It only depends on hospital blood

bank human and material resources andpatients risks management capabilities

major crossmatch versus typescreen

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