Blood banking:- part 3 – Blood Donation Procedure, Blood Components and Their Indications
Procedure to collect blood from the donor.
- Make the donor comfortable and assure him about safety.
- Give some time to the donor to acclimatize with the atmosphere.
- Now apply the blood pressure cuff above the elbow and give a pressure of 20 to 40 mmHg.
Cleaning the site:
- Now clean the site of venipuncture thoroughly.
- Can use chlorhexidine, or 1% tincture iodine, or 1% PVP iodine.
Collection of the blood (Procedure for the collection of blood bag):
- Keep the blood pack below the level of the donor.
- Can keep the pack in the balance.
- Now increase the blood pressure to 60 to 80 mmHg till the vein is prominent. Ask him to clench their fist.
- Insert the needle into the vein; as blood comes out, remove the bead, which prevents the blood from entering the pack.
- Now reduce the pressure in the cuff.
- Carefully and slowly mix the blood with the anticoagulants.
- When blood donation is complete, reduce the pressure to 0 in the cuff.
- Clamp the blood pack (bag).
- Take out the needle and apply the pressure on the venipuncture site.
Precaution after the collection of blood (Post blood donation precautions):
- Please don’t allow the donor to sit immediately; ask him to lie down for at least 5 to 10 minutes.
- Sometimes the donor gets headaches, nausea, and dizziness.
- Donor blood pressure may become low.
- Label the pack and make at least 4 to 5 tubing segments for further testing.
- Allow the blood to cool down before refrigeration is done. This period should not exceed more than one hour.
Before the donated blood is released, the following tests are done:
- The following tests are done on the donor blood and the serum.
- The donor’s blood grouping ABO is verified.
- Verify the Rh typing. Rh-negative blood is reconfirmed.
- Reverse blood ABO grouping is done on the donor serum.
- Antibody screening is done by the enzyme and antiglobulin method.
- Perform the VDRL, HBS, HCV, and HIV.
- The donor’s blood grouping ABO is verified.
- After doing all these tests, you can now release the blood pack for donation to the patient.
Blood components most common in use are:
- Whole blood.
- Fresh frozen plasma.
- Packed red blood cells.
- Frozen red blood cells.
- Human serum albumin.
- Human immune serum globulin.
- Antihemophilic factor concentrate (cryoprecipitate).
- Factor IX concentrate.
- Platelets concentrate or platelets-rich plasma.
- White blood cell poor blood (where the white cells are removed).
- Donors can donate the blood at intervals of 8 weeks.
- Healthy individuals can donate blood every 5 to 7 days for a limited period of time around 1 to 2 months.
- In the above donor, an iron supplement is needed.
Autotransfusion (autologous transfusion):
This is the collection of blood and subsequent transfusion of the patient’s own blood.
Can donate blood every 5 to 7 days before elective surgery.
Advantages: This will prevent all problems of the transfusion reaction, transfusion-related infections, and also avoid religious beliefs.
Packed red blood cells:
Packed RBCs consist of refrigerated stored RBCs without three-fourth plasma. The majority of plasma is removed.
Advantages: This will avoid overloading and pulmonary edema.
- This is especially useful in patients with anemia where plasma is not needed.
- It is used in pure RBCs deficiency.
- In case if antibodies are present in the plasma of the donor.
- This also prevents other problems of the stored blood like raised levels of potassium or ammonium level.
Washed red blood cells:
- These are the packed red blood cells that were washed several times with saline, followed by centrifugation.
- This will remove >90% of the white blood cells, and also removes platelets and plasma.
- 10% to 20% RBCs are also lost in washing.
- Indications: There are very few indications for washed red blood cells.
- This cell washing will remove donor antibodies and is useful in IgA immune reactions
- Washed RBCs are used for the treatment of paroxysmal nocturnal hemoglobinuria.
- Washed RBCs should be used within 24 hours after preparation (washing).
How to make Fresh Frozen Plasma:
- Fresh frozen plasma is prepared from the fresh whole blood within 6 hours after collection.
- Fresh frozen plasma is separated from the RBCs after centrifugation at 4 °C temperature and immediately is frozen.
- Before giving to the patients, it needs to be thaw at 37 °C for at least 20 minutes or until the thawing is complete.
- Don’t delay after thawing to transfuse into the patient because factors V and VIII deteriorate in a short time.
- The thawing process may be accelerated by an agitator machine and a specially designed microwave.
- Used for: Fresh frozen plasma is the choice treatment for coagulation factor deficiency such as factor VIII (Hemophilia A), von Willebrand’s disease, or fibrinogen.
How to make Cryoprecipitate:
- Cryoprecipitate is prepared from fresh frozen plasma; it is the material that does not become totally liquid when fresh frozen plasma is slowly thawed and the major part has liquefied.
- Advantage: The major advantage over fresh frozen plasma is the reduced volume of fluid that is transfused.
- Each unit contains around 150 mg of fibrinogen.
- Cryoprecipitate is good to treat von Willebrand’s disease and Hemophilia A.
- Contents: Cryoprecipitate contains 50% of the factor around 50% factor VIII and von Willebrand factor activity.
- Fibrinogen and factor XIII is around 20% to 40%.
5% albumin can be used instead of plasma to restore colloid oncotic pressure.
In a normal person, 500 ml of blood contains 11 grams of albumin. 70% of the albumin is synthesized in the liver.
Indications: To restore the colloid oncotic pressure.
- This is used in hypovolemic shock due to massive acute blood loss or extensive burns.
- It is not given in hypoalbuminemia due to chronic liver disease or loss through kidneys or gastrointestinal tract.
- Platelets are supplied in units that contain platelets equivalent to one point of blood roughly 5.5 x 1010.
- Can get multiple units from a single donor by means of platelet apheresis.
- Platelets are store at room temperature.
- A single unit of the platelets will raise the platelet count to 7,000 to 11,000/cmm.
- Platelets should be transfused as soon as possible after collection to get the maximum functions of the platelets.
- Indications: Platelet transfusion may be prophylactic or therapeutic.
- Therapeutic transfusion is done when it is severe thrombocytopenia <50,000/cmm and there is severe acute bleeding.
- When there is thrombocytopenia, but no bleeding then can give prophylactically platelets transfusion.
- Bleeding time may be the guide for the platelets transfusion.
- It is not indicated in idiopathic thrombocytopenia (ITP) unless the patient is actively bleeding.
- No use of platelets transfusion, in case of drug-induced thrombocytopenia unless the drug is stopped.
Blood components and their indications:
|Packed RBCs||Only RBCs without plasma||
|Fresh frozen plasma||Plasma separated and frozen in 8 hours of collection.||
|Granulocytes collected by apheresis||Granulocytes are collected by apheresis.||
|Platelets collected by apheresis||platelets collected by apheresis and volume is 200 to 300 mL||
Effects of temperature on the storage of the blood: