exam 3 flashcards

what is the next step after finding ABID?

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

• <37C

• only C3d pos

• no reactive eluate

• Ab in serum

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)

<0.5 = round down +1

0.5 = round up + 1

criteria for RhIg

• mom Rh neg

• neg for anti D

• infant D pos

blood criteria for IUT/exchange transfusion

• type O

• Ag negative

• <7 days old

• CMV neg/leukocyte reduced

• irradiated

• Hgb S neg (sickle cell)

• washed

how to remove IgM

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

how to remove IgG

chloroquine diphosphate

how to make kell neg cells

ZZAP