Therapeutics in Hematology 2 Flashcards
levels of the apheresis
bottom: rbcs
middle: platelets, wbc
top: plasma and coagulation factors
uses for apheresis
treatment in mg or gbs
- plasma has the antibodies to cause mg or gbs
- replace with normal plasma and reinfuse
indications of collections in apheresis
plateletpheresis (1 donation = 6-8 units)
plasmapheresis (igs)
leukapheresis (wbs, lymphocytes, granulocytes)
peripheral blood stem cells (hct)
erythrocytapheresis
neocytapheresis
indications for removal in apheresis
therapeutic plasma exchange (gbs, chronic demyelinating polyneuropathy, mg, thrombotic thrombocytopenic purpura)
therapeutic leukapheresis (leukemia, hyper-viscosity syndromes)
therapeutic thrombocytapheresis (essential thrombocythemia)
therapeutic red cell (polycythemia vera)
steps in blood testing
- verify patient identification
- collect and label patient sample
- abo and rh typing
- antibody screening
- compatibility testing/cross matching
- select compatible units for transfusion
forward vs reverse grouping
forward: use anti-a, anti-b, anti-d to detect a, b and rh(d) antigens on rbc
reverse: use type a and b rbc to detect anti-a and anti-b antibodies in recipient plasma
purpose of antibody screening
to check of there are low level antibodies which can lead to incompatible transfusion
steps in antibody screening
use type o to detect antibodies
detect antibodies = use panel type o to identify recipient antibodies then provide rbc units which lack antigens
types of compatibility testing
serological crossmatch: mix donor and recipient
electronic crossmatch: use computer algorithms (only for recipients with neg antibody screen and indep confirmed blood)
t/f if crossmatch-compatible blood products cant be found, incompatible units may be used at the physician’s discretion if transfusion outweighs the risk of incompatible blood
true
major crossmatch
- get plasma or serum from patient and add to donor cells
- incubate at 37 for 1 hr
- transfuse
results of major corssmatch
(+) agglutination = incompatible
(-) agglutination = compatible
risks of transfusion complication reactions
febrile nonhemolytic transfusion reactions
allergic
delayed hemolytic
most unlikely: anaphylactic
risk of transfusion infectios
most common hep b
hep c, hiv, htlv, least: malaria
other complications in transfusion
rbc allosensitization
hla allosensitization
gvhd
t/f you can predict allergic reactions
false
risk of hiv transmission is due to ___
screening
most common cause of ahtr
clerical error
mechanism of ahtr
incompatible donor of rbcs coated with recipient serum igm antibodies that fix complement leading to intravascular hemolysis
cytokines = fever and chills dat = (+) igg and complement
timing of ahtr
first 15 mins
manifestation of ahtr
fever and chills
back or infusion site pain
hypotension/shock (dic)
hemoglobinuria (due to lysis)
peripheral blood smear shows schistocytes and spherocytes
management of ahtr
stop transfusion
hydration to maintain urine output >100 cc/hr
diuresis with mannitol
vasopressors
dic: fresh frozen plasma, platelets, cyroprecipitate
most frequently reported transfusion reaction
febrile nonhemolytic transfusion reactions
more common in platelet transfusions
mechanism for fnhtr
increased pyrogenic substances (tnf-a, il1b, il6)
manifestation of fnhtr
fever and chills during or until 2 hrs after transfusion
prevention of fnhtr
leukocyte reduction (reduced due to universal leukoreduction) premedication: acetaminophen
t/f leukoreduction is done in the philippines
false, fnhtr is not that high and cost prohibitive
ddx for fhtr
ahtr and transfusion related sepsis
negative hemolysis workup in fnhtr
treatment in fnhtr
antipyretics (acetaminophen)
meperidine (demerol) for severe
1 cause of transfusion related fatality in us
transfusion related acute lung injury
mechanism for trali
page 3
common donor source in trali
multiparous women
timing of trali
within 6 hours, common wihtin 2 hours
prevention of trali
- do not transfuse when not needed
- implicated donors should be deferred
- male plasma use
- testing
treatment for trali
supportive care (o2 and intubation)
treatment for allergic reactions
diphenhydramine
can restart transfusion when hives clear
manifestation of moderate allergic transfusion reactions (anaphylactoid)
upper/lower airway obstruction
+/- cutaneous manifestations
manifestation of severe allergic transfusion reactions (anaphylactic)
lower airway obstruction skin findings (urticaria, angioedema, generalized pruritus)
mechanism or severe allergic rxn
iga deficient recipient who has formed anti-iga of ige class
timing for severe allergic rxn
very early
prevention of severe allergic rxn
test for iga deficiency
treatment for severe allergic rxn
stop transfusion
steroids or epinephrine
mechanism of dhtr
patient exposed to non-abo red cell antigen that is not present in their own rbcs
antibodies seen in dhtr
kidd, duffy, kell ab
timing of dhtr
> 24h but <28 d
common setting for transfusion associated graft vs host disease
donor is first degree relative
mechanism for ta-gvhd
page 4
manifestation of ta-gvhd
fever 7-10 days post transfusion face/trunk rash mucositis nausea/vomiting watery diarrhea hepatitis pancytopenia and marrow aplasia
prevention of ta-gvhd
get other donor
radiation in blood products
common setting for transfusion related sepsis
rbc transfusions
timing for trs
within first few minutes of transfusion
manifestation of trs
rapid onset high fever
symptoms similar to hemolysis
organisms typical in blood products
rbc: g- rods, yersinia enterolitica
platelets: g+ cocci, g- rods
mechanism for ptp
platelet specific antibodies against GPIIIa on surface of platelets
timing for ptp
7-10 d
prevention and treatment for ptp
avoid further platelet transfusions
ivig
plasmapheresis
mechanism for alloimmunization
occurs after transfusion of products with low frequency unrecognized antigens
t/f alloimmunization can cause refractoriness of transfusion
true
treatment for alloimmunization
limit transfusions
rational blood use
single donor apheresed platelets
hla matched platelets
nonimmune reactions
transfusion associated circulatory overload
hypothermia
electrolyte toxiciity
mechanism of taco
congestion due to volume of transfusion (manifest in pts with renal and heart failure)
treatment for taco
diuretics
aliquot of blood units
mechanism of hypothermia
due to transfusion of refrigerated or frozen blood = cardiac dysrhythmia
treatment for hypothermia
warm water bath
mechanism of hypocalcemia
due to citrate in preservation of plasma and prbc
- edta (anticoagulant and preservative)
mechanism of hyperkalemia
leakage of potassium during storage
mechanism of iron overloasd
transfuse regularly (>14 units prbc/year; thalassemia or aplastic anemia)
t/f after the 5th unit of transfusion it’s considered iron overload
false, 10th unit
treatment for iron overload
rational blood use
chelation therapy
