BB Lec - Current Trends

Question 1

Creating RBCs in the laboratory

Answer 1

(blood pharming)

Question 2

mechanism for forming O-type RBCs

Answer 2

The use of enzymes that remove the carbohydrate moieties of the A and B antigens

Question 3

Current research on blood substitutes is focused on two areas:

Answer 3

hemoglobin-based oxygen carriers (HBOCs) and per- fluorocarbons (PFCs)

Question 4

Originally developed to be used in trauma situations such as accidents, combat, and surgery,

Answer 4

RBC substitutes

Question 5

are intimately involved in primary hemostasis,

Answer 5

Platelets

Question 6

interaction of platelets and the vascular endothelium in halting and preventing bleeding following vascular injury.

Answer 6

hemostasis

Question 7

cellular fragments derived from the cytoplasm of megakaryocytes present in the bone marrow.

Answer 7

Platelets

Question 8

They do not contain a nucleus

Answer 8

Platelets

Question 9

platelet DNA found in__

Answer 9

mitochondria

Question 10

average diameter of platelets

Answer 10

2 to 4 μm

Question 11

normal plt count

Answer 11

150,000 to 350,000 per μL

Question 12

how many days do PLT circulate

Answer 12

9-12 days

Question 13

how much plt is sequestered in the microvasculature of the spleen as functional reserves.

Answer 13

30% of the platelets

Question 14

Used to treat bleeding as associated with thrombocytopenia

Answer 14

PLT

Question 15

Efficacy of transfused platelets: estimated from __

Answer 15

CORRECTED COUNT INCREMENT

Question 16

CORRECTED COUNT INCREMENT estimates what of platelets?

Answer 16

Efficacy of transfused platelets:

Question 17

measured after transfusion; does not evaluate or assess the function of the transfused plt

Answer 17

CCI

Question 18

Transfused prophylactically to increase the circulating platelet count in hematology-oncology thrombocytopenic patients to prevent bleeding secondary to drug or radiation therapy

Answer 18

PLT

Question 19

utilized in some instances to treat other disorders in w/c platelets are qualitatively or quantitatively defective because of genetic reasons

Answer 19

PLT

Question 20

MAJOR PROBLEM whenplatelet transfusions were given as freshly drawn whole blood or platelet-rich plasma

Answer 20

circulatory overload

Question 21

Today, platelets are prepared as (2)

Answer 21

concentrates from whole blood

by apheresis

Question 22

The 2007 National Blood Collection and Utilization Survey found that only ??% of platelet doses in the United States were whole blood derived (WBD).

Answer 22

17

Question 23

still remain as the primary means of treating thrombocytopenia

Answer 23

Platelets

Question 24

Storage limit of PLT

Answer 24

5 DAYS

Question 25

The two main reasons for the 5-day shelf-life for platelets are

Answer 25

>bacterial contamination at incubation of 22°C | >loss of platelet quality during storage (known as the platelet storage lesion

Question 26

loss of plt quality and viability

Answer 26

Plt storage lesion:

Question 27

assoc with loss of membrane integrity

Answer 27

Absence of platelet swirling:

Question 28

During the storage of PCs in plasma, the principal buffer is

Answer 28

bicarbonate

Question 29

PLT routinely stored at what temp with continuous agitation (primarily flatbed and circular agitators for up to 5 days).

Answer 29

20°C to 24°C,

Question 30

In the United States, platelets are being stored WHERE, unless a platelet additive solution is used.

Answer 30

in a 100% plasma medium

Question 31

Initially, platelets were stored at ___, based on the successful storage of RBCs at this temperature range

Answer 31

1°C to 6°C

Question 32

what happens to PLT when stored at 1-6C?

Answer 32

becomes spherical from discoid

Question 33

loss of PLT shape at 1-6c is due to

Answer 33

microtubule assembly

Question 34

a study by _______ showed that cold storage at 1°C to 6°C resulted in a marked reduction in platelet in vivo viability, manifested as a reduction in in vivo life span, after only 18 hours of storage. This study also identified for the first time that 20°C to 24°C (room temperature) should be the preferred range, based on viability results.

Answer 34

Murphy and Gardner

Question 35

aside from the temp considerations, platelets must also be ___ during storage

Answer 35

agitated

Question 36

has been shown to facilitate oxygen transfer into the platelet bag and oxygen consumption by the platelets.

Answer 36

agitation

Question 37

what happens when pH was reduced from 6.8 to 6.2

Answer 37

platelets progressively changed shape from disks to spheres

Question 38

The ___ being used for storage were identified as being responsible for the fall in pH because of their limiting gas transfer properties for oxygen and carbon dioxide

Answer 38

containers

Question 39

1st generation containers

Answer 39

polyvinyl chloride (PVC) containing phthalate plasticizer

Question 40

2nd gen containers

Answer 40

PVC or polyolefin plastic

Question 41

For most PVC containers,_____ used to increase gas transport

Answer 41

alternative plasticizers

Question 42

two alternative plasticizers

Answer 42

trimellitate & citrate based a

Question 43

____ is determined by measuring pre-transfusion and post-transfusion platelet counts (1 hour and/or 24 hours) and expressing the difference based on the number of platelets transfused (corrected count increment)

Answer 43

Platelet viability

Question 44

The observation of the ____ caused by discoid platelets when placed in front of a light source has been used to obtain a semi-qualitative evaluation of the retention of platelet viability properties in stored units

Answer 44

swirling phenomenon

Question 45

indicates the capacity of platelets to circulate after infusion without premature removal or destruction.

Answer 45

Viability

Question 46

Platelets have a life span of ??days after release from megakaryocytes.

Answer 46

8 to 10

Question 47

is defined as the ability of viable platelets to respond to vascular damage in promoting hemostasis.

Answer 47

Function

Question 48

The major concern associated with storage of platelets at 20°C to 24°C is the ?

Answer 48

potential for bacterial growth

Question 48

Company developing the technology of blood typeconversion

Answer 48

ZymeQuest

Question 49

Company awarded the contract to develop a system to produce O negative RBCs

Answer 49

Arteriocyte

Question 50

Blood substitutes areas of research

Answer 50

Hemoglobin-based oxygen carriers | Perfluorocarbons (PFCs)

Question 51

How much platelet is discarded by blood supplier or hospital blood bank

Answer 51

Approx 30% of platelet inventory

Question 52

Identified as being responsible for the fall of pH of PLT due to their limiting gas transfer properties for oxyen and carbon dioxide

Answer 52

Containers for storage

Question 53

Disadvantages of culture methods for detection of bacterial contamination of PLT

Answer 53

Product loss due to sampling False negative results Costs Delay in product release, further reducing already short shelf-life Logistical problems of culturing WBD platelets