Chapter 36 Transfusion Medicine

Front 1

review the basic qualification for blood donors

Back 1

10.5 ml/kg body weight (110lb), 50kg limit
temperature </=99.5*F or 37.5*C
blood pressure </= 180/100
Hb or Hct must be >/=12.5

Front 2

give the deferral period for each
isotretinoin:
acitretin:
etretinate:

Back 2

isotretinoin: 1 month defferal
acitretin: 3 year defferal
etretinate: indefinite deferral

Front 3

defferals for
Chagas' disease:
accidental needlestick:
syphilis:
malaria, confirmed infection:

Back 3

Chaga's disease is an indefinite deferral;
accidental needlestick exposure and syphilis both=1 year defferal;
after becoming asymptomatic, a malaria patient must wait 3 years to donate

Front 4

how long may red blood cells be stored if they are preserved with CPDA-1?
if an additive solution is used?

Back 4

with CPDA-1, the storage period is 35 days;
additive solutions (AS-1, AS-3, AS-5) allow for 42days

Front 5

cryoprecipitate was once used to treat hemophilia A, it contains factor VII; its most common use is a source of

Back 5

fibrinogen

Front 6

risk of transmission of hepatitis B virus is?
risk of transmission of hepatitis C virus is?

Back 6

HBV: 1/250,000
HCV: 1/2,000, 000

Front 7

what is the risk of HIV transmission?
what demographic group cannot be safely screened with the current EIA test?

Back 7

HIV: 1/2,000,000
group O viral isolates, such as may be seen in persons from western Africa, are not reliably detected with the EIA platform in current use

Front 8

2 clues seen in a recipient to bacteria contamination of a unit of blood?

Back 8

acute fever, low blood pressure;
GNR=RBC
GPR=platelets
GNR often more lethal

Front 9

28yom O pos, never been transfused, 15 minutes in to the transfusion...temp 36.8 to 38.9, blood pressure falls 110/75 to 90/40, he complains of nausea and chills. the transfusion is stopped, patient is treated with IV fluids; the intern ask what test should be ordered?
the unit is returned to blood bank. It is labeled Group A. Outline the test to be ordered?

Back 9

Acute hemolytic transfusion reaction;
DAT both on pre transfusion and post transfusion samples from patient- the pre DAT should be negative and the post DAT should be positive ;
re-type and re-crossmatch the patient and the unit
spin down the post-sample to look for gross hemolysis;
the intern should order haptoglobin, UA, LDH and indirect bilirubin

Front 10

what medication may prevent a mild allergic reaction, such at urticaria?

Back 10

oral or IV antihistamine--diphenhydramine 50-100mg

Front 11

glycerolization of red cells allows them to be frozen and stored for up to 10 years at -65*C; once thawed and deglycerolized, the shelf life and storage requirements are?

Back 11

open- 24 hour shelf life at 1 -6*C
closed- 14 day shelf life

Front 12

leukocyte reduced RBCs contain less/WBCs per unit

Back 12

5 x 10^6 WBCs per unit

Front 13

what are the shelf life and storage temperature for fresh frozen plasma (FFP) that is still frozen

Back 13

-18*C for a year

Front 14

outline the storage parameters for platelets?

Back 14

stored at room temperature (20-24*C) with gentle agitation for 5 days from the date of donation

Front 15

how does anemia affect cardiac output, red cell 2,3-DPG concentration and the oxygen-hemoglobin dissociation curve?

Back 15

anemia increases cardiac output, increases 2,3-DPG levels in RBCs to facilitate the offloading of oxygen, and shift the dissociation curve to the right

Front 16

what are the radiation parameters(cGy) for irradiated blood products?;
what is achieved by irradiation?

Back 16

radiation dosage is recommended as 2500cGy to the center of the unit bag with at least 1500cGy to the outer portions of the bag; this prevents any lymphocytes in the unit from dividing; lymphocytes are the bad actor in graft-versus-host disease

Front 17

what is the required platelet count for random-donor platelets?
apheresis platelets?

Back 17

random donor platelets: 5.5 x 10^10
apheresis: 3.0 x 10^11

Front 18

corrected count increment (CCI)?

Back 18

CCI= (post transfusion platelet increment x body surface area)/ (platelets transfused (x10^11))

Front 19

what are the goals for the HbS level and Hct after a red cell exchange transfusion in sickle cell disease patient?
30-30 rule

Back 19

HbS </=30%
Hct 30

Front 20

what is massive transfusion?

Back 20

replacement of one blood volume within 24hours; for the average adult this would be 10 units of packed RBCs and 10 units of plasma

Front 21

how long can pretransfusion blood sample be used in a patient who has been pregnant or transfused in the past 3 months
*rule of 3's

Back 21

3 days

Front 22

why there has been a reduction in febrile non hemolytic transfusion reactions since the advent of universal leukocyte reduction?

Back 22

the febrile reations have been attributed to the presence of cytokines form donor white blood cells which stimulate a febrile response in the patient; prestorage leukoreduction eliminates most of the WBCs to limit cytokine generation upfront; Leukoreduction will prevent transfusion of most of the donor WBCs but the cytokines which have already been produced and have leaked out form the WBCs will still be transfused to the recipient

Front 23

what are the two mechanisms of pathogenesis in transfusion-related acute lung injury?

Back 23

1)donor antibodies to neutrophils or to HLA antigens react with the recipient's WBCs and cause aggregations of WBCs in the pulmonary circulation with resultant capillary leakage and edema
2) the presence of lipid inflammatory mediators in the unit that activate already primee recipient neutrophils to cause capillary leakage and injury

Front 24

list two strategies to reduce the incidence of CMV transmission by blood products?

Back 24

Leukoreduction helps, as CMV is carried in leukocytes;
Provide seronegative products to recipients; while the term CMV-negative is used, no test for CMV DNA is performed, rather these units from donors who have very low or negative levels of anti-CMV IgG ...indicating that they have not been exposed to the virus

Front 25

benefit of plasma transfusions in the following scenarios
*56 yow with PT 1.4 times the midpoint of the reference range, scheduled for thoracentesis?
* 71yom on warfarin with INR of 5.3, hit head in a fall at home?
*33 yow thrombotic thrombocytopenic purpura, starting therapeutic plasma exchange?

Back 25

56yow-no benefit from 1-2 units of FFP
71yom & 33yow much more beneficial
FFP is appropriate therapy to reverse the effects of warfarin, particularly when there is a risk of bleeding; FFP contains the enzyme metalloproteinase, which is deficient in cases of TTP, so FFP would be useful either as the replacement fluid for plasma exchange, or as a simple transfusion