exam 3 flashcards

what is the next step after finding ABID?

phenotype pt to make sure they are Ag negative for corresponding Ab (confirm ID)

rule of 3

* 95% confidence
* requires 3 rule outs and 3 rule ins when IDing an Ab

how to calculate number of units when finding Ag negative blood?

\# units/Ag negative frequency

Ab screen

detects Abs in pts requiring transfusions, pregnant women, blood donors, pts with suspected transfusion rxns

what cells are used in ABID?

type O cells with known Ags

autocontrol

pt plasma + pt cells to ID an autoab

E/V hemolysis

Ag/Ab complexes cleared by liver and spleen

I/V hemolysis

* complement activated
* coag cascade = DIC

acute hemolytic transfusion rxn

* fever, chills, pain at infusion, hgburia/emia
* rapid
* ABO incompatibility, clerical error
* dec HH, hapto; inc bili
* pos/neg DAT
* post transfusion screens negative

delayed transfusion rxn

* jaundice, fever
* 5-7 days
* previous alloimmunization (low titer)
* dec HH
* pos DAT
* pos post transfusion screen

non immune transfusion reactions

febrile, allergic, anaphylactic, TAGVHD, bacterial

febrile transfusion reaction

* fever, nausea, vomiting, headache
* 1-2hrs post
* HLA Ab to donor Ag OR cytokines

how to resolve febrile transfusion rxn

leukocyte reduced components

allergic transfusion rxn

* hives, wheals, itching
* rapid
* Ab to proteins

how to resolve allergic transfusion rxn

give antihistamines but usually do not stop the transfusion

anaphylactic transfusion rxns

* severe wheezing, cough, bronchospasms
* rapid
* IgA def (plasma components)

how to resolve anaphylactic rxns

* check IgA levels
* give IgA def plasma OR washed rbcs/plts

TAGVHD

* fever, rash on trunk, sepsis, hemorrhage, death (90% mortality)
* 3-30 days
* donor lymphs against recipient

how to resolve TAGVHD

gamma irradiation on all blood components

bacterial transfusion rxns

* fever >2, abd cramps, diarrhea, DIC
* rapid
* commonly y. enterocolitica

how to resolve bacterial transfusion rxns

visual inspection of units (flocculation, swelling, darkening)

TRALI

* resp distress, hypoxemia, pulm edema, fever, hypotension
* 1-6 hrs
* donor HLA Abs attack pt wbcs
* give resp support

TACO

* dyspnea, severe headache, peripheral edema, CHF, hypertension, inc BNP
* 1-6 hrs
* volume overload
* give diuretics

warm AIHA

* 37C
* pos IgG/C3d
* reactive eluate
* Ab in serum
* adsorption elution

CAS/CHD/PCH

*

drug adsorption

* 37C
* only pos IgG
* reactive eluate
* Ab in serum
* penicillin, cephalothin, quinidine

immune complex

* 37C
* only pos C3d
* no reactive eluate
* Ab in serum
* rifampin, phenacetin, quinine

membrane modification

* 37C
* pos IgG/C3d
* no reactive eluate
* no Ab in serum
* keflin, cephalothin

drug induced (true autoimmunity)

* 37C
* only pos IgG
* reactive eluate
* Ab in serum
* methyldopa, L-dopa

ABO HDN

* least severe most common
* O mom with A, B, AB baby (IgG anti A,B)
* treat with bililights
* weakly pos DAT

Rh HDN

* most severe, not common b/c rhogam
* significantly inc bilirubin = kernicterus
* need sensitization so not in first pregnancy
* treat: IUT/exchange transfusion
* strong pos DAT, inc bilirubin

other Ab HDN

* K, Fya, c
* treat with IUT/exchange transfusion
* Ab titration (2 fold increase)

how to monitor fetal distress

* Ab titer (2x inc)
* bilirubin (OD 450nm, liley graph)
* lung maturity (L/S ratio, PG)

rosette test

screen test for FMH, qual

kleihauer betke

* quantitates the volume of a FMH
* acid elution: hgb F is resistant, washes away moms cells (ghost cells)

RhIg vial calculations

\# fetal cells/2000 = % fetal cells

% fetal cells x 50 = ml fetal blood

ml fetal blood/30 = # of vials

* 30 (whole blood) 15 (pRBCs)

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criteria for RhIg

* mom Rh neg
* neg for anti D
* infant D pos

blood criteria for IUT/exchange transfusion

* type O
* Ag negative
*

how to remove IgM

any thiol reagent (DTT, 2-ME, AET)

how to remove IgG

chloroquine diphosphate

how to make kell neg cells

ZZAP