MMSC 409 Exam 1

immunohematology

the study of the immune aspects of hematology to provide safe therapeutic blood products to patients

antigen (Ag)

a substance that is recognized by the body as being foreign, which causes an immune response

antibody (Ab)

a protein substance that is secreted by plasma cells in response to an antigen

hemolysis

the disruption of the RBC membrane, causing release of hemoglobin into the plasma

agglutination

the clumping of RBCs (or other particulate) due to interaction of antibodies with their corresponding antigen

accuracy in blood banking

100% accurate to avoid severe transfusion reactions due to incompatibility

Accuracy w/ recording

Donated blood units need to be typed properly to ensure they are given to the right patient

Accuracy w/ Interpreting

typed properly to ensure they receive the correct units of blood

blood test at donor collection facility

-ABO and Rh typing

-infectious disease testing: syphillis, hepatitis B & C, AIDS/HIV, HTLV I & II, west nile virus, Chagas disease (T. cruzi)

-ABO and Rh types reconfirmed

blood test at transfusion center

-reconfirmation of ABO type (make sure it matches the label)

-pre-transfusion testing on patient: ABO, Rh type, antibody screen, crossmatch

Food and Drug Administration (FDA)

regulates all blood component manufacturers, distributors and medical laboratories in the US

-provides licensure and approves all methods and products used for blood collection

-center for biological evaluation and research (CBER)

-control blood collection and manufacturing of pharmaceuticals

AABB

-Standards for blood collection centers and transfusion centers

-voluntary accreditation of either people or facilities

-writes technical manuals

-ensures that standards for CMS (Medicare and Medicaid) are met

College of American pathologists (CAP)

-voluntary accreditation of clinical laboratories

-administer proficiency testing for clinical laboratories

Past blood banking issues

Multiple blood groups

Circulatory overload

Blood storage and expiration

Multiple blood groups

Even with knowing about ABO there were still transfusion reactions going on that lead to discovery of other blood groups

Circulatory overload

People who only needed 1 component of blood were given whole blood that gave an overload of cells and volume, leading to production of apheresed products

Blood storage and expiration

Blood that was collected would expire really quickly so research was need to figure out what would extend the shelf life

RBC membrane

Phospholipid bilayer

Semipermeable

Integral proteins

Peripheral proteins

Protein cytoskeleton

Spectrin

(RBC Membrane) Phospholipid Bilayer

Containing glycolipids and immunoproteins

(RBC Membrane) Semi-permeable

Ability of molecules to pass in and out of the RBC membrane to maintain Na+ and K+ concentrations.

ATP powered => K+ into cell Na+ out

(RBC Membrane) Integral Proteins

Extend from the outside through the bi-layer and into the cytoplasm

(RBC Membrane) Peripheral Proteins

Are present on internal side of the bilayer forming the cytoskeleton

(RBC Membrane) Protein Cytoskeleton

Is a mesh that supports the bi-layer

(RBC Membrane) Spectin

An important protein in the cytoskeleton of RBCs that is phosphorylated by ATP so that the cell remains flexible

Flexibility of the RBC membrane

So they are able to pass through small blood vessels.

RBCs that lose this ability (low ATP= nonfunctional spectrin) will be broken down in the spleen

Permeability of the RBC membrane

Ions become imbalanced (low ATP=non functional pumps) the cells become dehydrated and rigid and are removed from circulation

Hemoglobin Structure

Protein in RBCs composed of 2 alpha chains and 2 beta chains

Hemoglobin Function

Carries O2 to tissues, When B chains spread apart it allows 2,3 DPG to bind and causes release of O2 from the protein and into the tissues

hemoglobin-oxygen dissociation curve

a graph that associates the % saturation of oxygen on the hemoglobin molecule with a particular pressure of O2

Curve shows oxygen carrying capacity and affinity

The % of oxygen that is being released into tissues is equal to 100% minus the % oxygenation of hemoglobin (the amount of O2 the hemoglobin holds on to)

Right shift on Curve

MORE oxygen delivery to tissues

-hemoglobin is more weakly bound to O2 (decreased oxygen carrying capacity)

-high temperatures

-high 2,3 DPG

-low pH (acidic)

Left shift on Curve

LESS oxygen delivery to tissues

-hemoglobin is more strongly bonded to oxygen (increased oxygen carrying capacity)

-low temp

-low 2,3 DPG

-high pH (basic)

Stored blood can undergo a (left or right) shift of the oxygen dissociation curve?

LEFT, due to the fact that 2,3 DPG has been depleted during storage

-causes decreased delivery of oxygen to tissues

2,3 DPG Purpose

A molecule that binds to the beta chains of oxyhemoglobin and forces the oxygen on the hemoglobin to be released into tissues

2,3 DPG Function

High concentrations will increase O2 delivery to tissues

Low concentrations will decrease O2 delivery to tissues (increased O2 carrying capacity of hemoglobin)

Additive Solutions Purpose

Used with RBCs to keep them viable after they have been removed from plasma and offer other benefits

Additive Solution to RBCs Benefits

Longer shelf life

Production of more products

Easier transfusions

(Add Solu./RBCs) Longer shelf life

Provide nutrients so RBCs are able to survive longer

(Add Solu./RBCs) Production of more products

Removing RBCs from whole blood and storing them in solution makes it possible for platelets and plasma to be used as separate therapies

(Add Solu./RBCs) Easier Transfusions

RBCs that are in solution instead of plasma is less viscous and easier to transfuse than whole blood

Anticoagulant

additive that is used to store RBCs and prevent clotting

ACD-A, CPD, CP2D

Anticoagulants

Contain citrate, monobasic sodium phosphate and dextrose

Expiration: 21 days

Store at 1-6 C

Citrate (Sodium citrate or Sitric acid)

an ingredient of anticoagulants which chelates calcium to prevent clotting

Monobasic Sodium Phosphate

A buffer that is present in anticoagulants to maintain storage levels of 2,3 DPG so that stored RBCs maintain their ability to deliver oxygen

Dextrose

An energy substrate that is present in anticoagulants to provide a substrate for Glycolysis so stored RBCs maintain ATP production

CPDA-1

Anticoagulant

Contains sodium citrate, monobasic sodium phosphate and dextrose

Expiration: 35 days (increased time is a big benefit)

Storage 1-6 C

Adenine

Additive to anticoagulant solutions that allows for increased production of ATP in stored RBCs

-Allows for longer storage times

AS-1, AS-5, AS-7

Additive

Contains mannitol, saline, adenine and glucose

Expiration 42 days

Mannitol

Additive solution ingredient that protects against hemolysis in stored RBCs

AS-3

Additive solution

Contains citrate & phosphate, saline, adenine and glucose

Expiration: 42 days

Citrate and Phosphate

2 ingredients that are used together to prevent hemolysis of RBCs in additive solution

Storage Lesion

A loss of viability and function due to biochemical changes that occur in stored blood

Storage Lesion Effects on RBCs

% of viable cells decrease

Glucose and ATP decrease

Lactic acid increases

More acidic pH

2,3 DPG decreases

Storage Lesion Effects on Curve

Left shift in O2 dissociation curve (less oxygen delivery to tissues)

RBC lifespan

120 days

Fetal Hemoglobin vs Adult

Has a higher affinity for O2, binds O2 more stably, and does not release it into tissues as easily

Expiration of whole blood

35 days

Methemoglobin

In ferric state and can no longer carry O2

Undergoes methemoglobin reductase pathway to carry oxygen again

Donor interview

Is conducted to promote the safety of the donor and the recipient

Weight for heterologous donation

110 lb

Temperature for heterologous donation

37.5 C / 99.5 F or lower

Pulse for heterologous donation

50-100 BPM

Blood pressure for heterologous donation

180/100 or lower

Hemoglobin (Hgb) for heterologous donation

Male: 13 g/dL or higher

Female: 12.5 g/dL or higher

Hematocrit (HCT) for heterologous donation

38% or higher

Questions asked to Donor

Time period since last donation

Past deferral

Health history

Medications

Pregnancy in the last 6 weeks/ever

Past Deferral Questions

Reasons of their own health (vitals out of range that would endanger their health)

Health History Questions

Surgery in the last 12 months

History of heart/lung/ liver disease

History of cancer

Abnormal bleeding tendencies

Unexplained weight loss

Medication Questions

Drugs, meds, antibiotics, aspirin in the last 3 days

Types of Deferrals

-permanent deferrals

-indefinite/ permanent deferrals

-temporary deferrals

Permanent deferral

confirmed HBsAg test (confirmed hepatitis B)

Indefinite/Permanent deferral

Hepatits or AIDS

Antibodies to hepatitis B (anti-HBc)

Hepatitis C infection

Positive for HIV, HCV, HTLV or T. cruzi

Previous donation gave recipient Hepatitis or AIDS

Sexual risk of AIDS (sex workers, gay men)

IV drug abuse

CJD risk factors (brain tissue transplant, use of bovine insulin, receive HGH)

Parasitic infections (babesiosis, Chagas disease, Leishmaniasis)

Leukemia or other cancers

Tegison medication (causes birth defects)

5 year deferral

Cancer in the last 5 years

3 year deferral

Malaria

Immigrant from malaria endemic country

Acitretin (causes birth defects)

12 month deferral

Recipient of blood/ blood products/ clotting factors

Close contact with viral hepatitis or AIDS

Sexual partner of someone on permanent deferral

Inmate of prison/ mental institution

Needlestick exposure

HbIG recipient (given in cases where HBV is a high risk)

Piercings/ tattoo

Acupuncture

Treatment for syphilis or gonorrhea

Travel to malaria endemic country

Rabies shot

Transplant or graft recipient

Cocaine use

4 week deferral

German measles (rubella) immunization

Proscar & accutane (birth defects)

2 week deferral

Immunizations for small pox, measles (rubeola), mumps, yellow fever or polio (SABIN)

whole blood collection

1)Select collection bag with desired anticoagulant

2)Ensure proper ID of patient

3)Prepare venipuncture site: scrub with iodine (clears normal flora of skin) and let dry completely

4)Draw donor blood

5)Mix blood and anticoagulant constantly (can be done by machinery)

6)Do not leave donor unattended

7)When sufficient volume has been collected, draw pilot tubes of blood

8)Make integral segments

9)Give donor post-collection instructions

Donor processing tests

ABO typing: forward and reverse type

Rh type: weak D test

Serum antibody screen

-if there are clinically significant Abs present, use the RBCs and discard plasma that contains the Abs

Serum antibody screen

Manufactured pooled screening units are used on donor units to look for clinically significant non-BO Abs

-Clinically significant Abs present, use the RBCs and discard plasma that contains the Abs

Infectious disease tests (donor processing)

Hepatitis B and C

HTLV I and II

HIV

Syphilis

West Nile virus

ALT

T. Cruzi

Zika virus

CMV (positive units can be used just not on immunocompromised)

Viral marker tests that require confirmation

If the test is positive, repeat and then use follow up test

(Not all require follow up test)

HBsAg Test

Viral Marker Test

If positive use inhibition test

Anti HIV1 test

Viral Marker Test

Confirm with western blot or gel electrophoresis

Donor unit label

Volunteer or paid donor

Component contained inside (RBCs, plasma, etc.)

ABO and Rh

Unusual test results

Anticoagulant type and amount

Volume of blood

ISBT donor number

Expiration date

Storage temp

Instructions/ precautions for use

ISBT donor number

Contains country, collection site, year and number of collection

Autologous blood donation

Donation of blood unit for yourself

-Donor and recipient are same person

-Blood collected for future use in surgery (preoperative collection)

Autologous donation requirements

Prescription from physician

No weight limit (can do low volume collection if < 100 lb)

No age limit

Hgb: at least 11 g/dL

HCT: at least 34%

Time period: 3 days since last donation

Autologous donation donor processing

-ABO and Rh testing to confirm that types match

-1st unit will be tested for hepatitis B and C, syphilis and HIV (if positive label as biohazard)

-Labeling is the same as Heterologous, but says "for Autologous use only"

Directed donor blood donation

The recipient of the blood chooses the donor

Done for elective surgery if recipient cannot donate blood for themselves

Directed donor requirements

-ABO and Rh compatibility of donor and recipient

-Donor meets physical and history requirements for heterologous donation

-Need prescription

Directed donor donor processing

Same tests are performed as heterologous donation

-Labeled normally with " for designated recipient" with recipient's ID

Irradiation

-A process that is used to inactivate any remaining WBCs (lymphocytes) that are present in a directed donor blood donation

-Prevents transfusion associated graft vs. host disease

-Required for 1st or 2nd degree relatives

Apheresis

Whole blood is withdrawn, a desired component is separated and retained and the remainder of the blood is returned to the donor

Apheresis types

-Plateletpheresis: platelets are collected

-Leukapheresis: granulocytes

-Plasmapheresis: plasma

-Erythrocytapheresis: RBCs

-HPC apheresis: hematopoietic progenitor cells

Apheresis requirements

-Meets all criteria for heterologous donation

-Sufficient time since last donation

-No bleeding/ fluid retention problems

-Aspirin free for 3 days

-Platelet count above 150,000 per uL

-WBCs above 4,000 per uL

-Serum protein 6 g/dL or higher

Double red donation requirement

Male: 130 lb, 5 ft 1 in

Female: 150 lb. 5 ft 5 in

HCT: 40% or higher

Heterologous whole blood donation frequency

8 weeks

-RBC mass needs to be replenished

Autologous whole blood donation frequency

3 days (as long as hemoglobin is fine)

Double red cell donation frequency

16 weeks

-RBCs need to replenish