Blood Bank Notes

Blood Bank: Donor Screening, Selection, and Blood Preservation

Introduction

Blood bank: Collection, processing, typing, and storage of blood and components for transfusion.
Also known as immunohematology: Study of immunologic principles in blood group antigens and antibodies.

Blood Collection Bags

Sterile interior with anticoagulant-preservative solution.
Closed system: Primary bag with satellite bags for component transfer, maintaining sterility and expiration date.
Open system: Increased contamination risk, changes component expiration date.

Blood Products as Therapeutic Drugs

Blood products are therapeutic drugs used for treating diseases.
Transfusion is a transplantation where cells must survive and function to have a therapeutic effect.

Blood Preservation

Goal: Provide viable and functional blood components.
At least 70% of transfused cells should remain viable for 24 hours.
Store blood in liquid state between $1^{\circ}C$ and $6^{\circ}C$ .

Approved Preservatives

ACD (Acid Citrate Dextrose): 21 days shelf life.
CPD (Citrate Phosphate Dextrose): 21 days shelf life.
CP2D (Citrate Phosphate Double Dextrose): 21 days shelf life.
CPDA-1 (Citrate Phosphate Adenine-1): 35 days shelf life.
CPDA-2 (Citrate Phosphate Adenine-2): 42 days shelf life.
Heparin: 2 days shelf life.

Anticoagulants and Red Cell Additives

Citrate: Calcium-removing agent, primary anticoagulant; may lead to hypocalcemia.
Dextrose: Provides energy for cells.
Citric Acid: Prevents caramelization.
Phosphate buffer: Increases ATP levels.
Adenine: Improves red cell survival.

RBC Storage Lesion

Decreased: % viable cells, glucose, ATP, pH, 2,3-DPG.
Increased: Lactic acid, plasma K, plasma Hgb.
Oxygen dissociation curve: Shift to the left.

Saline–Adenine–Glucose–Mannitol (SAGM)

Added to packed red cells after separating plasma and platelets.
Equivalent flow characteristics to plasma-reduced blood, 35–42 days storage.
Provides optimum red cell viability.

Storage Criteria for Blood Components

Whole Blood: $1$ to $6^{\circ}C$ , CPD/CP2D: 21 days, CPDA-1: 35 days.
Red Blood Cells: $1$ to $6^{\circ}C$ , CPD/CP2D: 21 days, CPDA-1: 35 days, AS-1/AS-3/AS-5: 42 days.

Sample Collection and Handling

Collect samples in plain red (serum), lavender, or pink (plasma) stopper tubes.
Serum separator tubes with gel are unacceptable.
Hemolysis interferes with test results.

Patient Identification

Confirm recipient’s ID from bracelet.
Full patient name and hospital number, physician's name required.

Donor Selection

Maximum collection: no more than $10.5$ ml of whole blood per kilogram of body weight including samples.
Donor interval: 8 weeks after whole blood donation.
Medical doctor must evaluate medications.
Medications affecting platelet function within 48 hours (e.g., aspirin) may restrict platelet donation.

Criteria for Donor Selection

Hematocrit $≥ 38%$ ; Hemoglobin $≥ 12.5$ g/dL.
Weight: Minimum $110$ lb / $50$ kg.
Temperature: $≤ 37.5^{\circ}C$ or $≤ 99.5^{\circ}F$ .
Age: $≥ 16$ years old.

Criteria for Autologous Donation

Requires physician order and blood bank medical director approval.
Cardiac release form for patients with cardiac disease.

Advantage

Eliminates risk of transfusion-transmitted infections, prevents alloimmunization, reduces transfusion reactions.

Disadvantage

Higher cost, high rate of wasted units.

Criteria for Apheresis Donation

Same as whole blood donation.
Apheresis instruments selectively remove/return components.

Types of Whole Blood Donation

Allogeneic donation
Directed donation
Autologous donation
Apheresis donation

Types of Donors

Voluntary/Non-remunerated: Low risk of transfusion-transmissible infections.
Family/Replacement/Direct.
Paid/Professional/Commercial: High risk of transfusion-transmissible infection.

Standard Procedures in Donor Screening

Registration
Medical history questionnaire
Physical examination
Blood collection
Post-donation instructions

Registration Information

Confirm donor’s identity (ID required).
Collect name, date and time of donation, address, telephone, gender, age/DOB.
Donor’s consent required: Inform donors of procedure/risks, provide educational materials.

Medical History Questionnaire

Ensures protection of donor and benefit to recipient.
Should be self-administered or by trained professional.

Donor Deferral

Temporary Deferral

Donor unable to donate for a limited time

Indefinite Deferral

Donor unable to donate for an unspecified period

Permanent Deferral

Donor never eligible to donate for someone else.

Blood Bank Section

Collects, stores, and prepares blood for transfusion.
Tests blood for group (ABO) and Rh type, antibodies, and compatibility.
Screens donor blood for blood borne pathogens.
Separates blood into components (packed cells, platelets, plasma, cryoprecipitate).
Offers autologous transfusion options.

Compatibility Test

Test between recipient and donor(s).

Tests Performed

Antibody screen: Detects abnormal antibodies in serum.
Direct antihuman globulin test (DAT): Detects abnormal antibodies on red blood cells.
Group and type: ABO and Rh typing.
Panel: Identifies abnormal antibodies in serum.
Type and crossmatch: ABO, Rh typing, and compatibility test.
Type and screen: ABO, Rh typing, and antibody screen.

Screening Tests

ABO Typing
Rh Typing
Antibody Screening
Serologic Test for TTI’s

Common Blood Components Requested

Whole Blood: Severe shock (blood loss of >25% blood volume).
Packed RBC: Same oxygen capacity with less volume.
Leukocyte reduced red cells: Prevents febrile non-hemolytic reactions.
Fresh Frozen Plasma: Coagulation disorders.
Platelet Concentrate: Severe thrombocytopenia, platelet dysfunction, bleeding risk.

Apheresis

Anticoagulant: Heparin
Advantage: Large volume, removal of unwanted substances

Common Apheresis Blood Components

Platelet apheresis
Leukapheresis
Plasmapheresis

Blood Typing

Forward Typing: Detection of antigens on patient's RBC using known antisera.
Reverse or Backward Typing: Detection of antibodies in patient's serum with known RBCs.

ABO Compatibility

Review ABO compatibility for red cells and plasma components.

Universal Donor/Recipient

Universal Donor: Group O.
Universal Recipient: Group AB.
Universal Donor for RBCs: Group O.
Universal Recipient for RBCs: Group AB.
Universal Donor for Plasma: Group AB.
Universal Recipient for Plasma: Group O.