Summary of study session VII
In study session VII you have learnt
- Blood transfusion is giving whole blood or part as red cell to replace blood lost through injury, surgery or disease. Indicated to promote oxygen delivery, treat anemia, improve coagulation problem and increase blood volume. Blood can be stored in a variety of solutions that contain citrate, phosphate, dextrose, and possibly adenine at a temperature of 40C
- The decision to transfuse red blood cells should be made after consideration of age and general condition of the patient such as the presence of coexisting cardiac, pulmonary, or vascular problems.
- The two most important blood group systems are the ABO and the Rh system. There are 2 antigens and 2 antibodies in the blood, all naturally occurring but not all of them occur in all people. The antigens are found in the red blood cells and are referred to as the A antigen and the B antigen. The antibodies occur in the serum and are referred to as the a' and ' antibodies. There therefore 4 kinds of blood groups according to their antigens and antibodies.
- The Rh antigen is called the D antigen. If this D antigen is present, the patient is said to be Rh positive. If it is absent, the patient is said to be Rh negative. Woman of child-bearing age should not receive Rh-positive transfusion if she is Rh negative.
- Rh-negative blood can be given if uncross-matched blood is required in a hurry because it contains no antibodies. Therefore, if uncross-matched blood is required, group specific Rh-negative blood is safest.
- Complications of transfusion reaction are many and include hemolytic reactions, contamination of blood and disease transmission, circulatory overload, air embolism, febrile and allergic reaction, hyperkalemia, citrate intoxication, hypothermia, metabolic acidosis, coagulation problems and massive transfusion.
- The blood pressure and the pulse rate must be checked every 5 minutes for the first 15 minutes after each new bottle of blood.
- Hemolytic reaction caused by incompatibility which the donor's red cells are destroyed by the antibodies in the recipient's serum. A hemolytic reaction can be produced by just a small quantity of mismatched blood.
- Signs of incompatible blood transfusion in the anesthetized patient include hypotension, tachycardia, cyanosis, skin rash, general oozing from the wound, later jaundice and oliguria. Acute circulatory collapse (cardiac arrest) and renal failure are the most serious complications and may lead to death. Diagnosis of transfusion reaction is established by hemoglobinuria.
- Treatment of a transfusion reaction includes stop transfusion, treat hypotension using crystalloids and adrenaline, and administer oxygen, hydrocortisone, furosemide and salbutaml.
- Massive transfusion is defined as the replacement of the total blood volume in less than 24 hours. Coagulation problems commonly result. Platelets and fresh blood or plasma are required.
- Precautions when transfusing large volumes of blood include giving calcium gluconate 10% (or chloride) at the rate of 10ml/6 units of bank blood. Give calcium solutions slowly over a period of 5 minutes. Administer furosemide 20mg if there is a decreased urine output.
- Monitor pulse, blood pressure, ECG, jugular vein enlargement, urine output, breath sounds during administering blood is essential.
Last modified: Wednesday, 16 November 2016, 5:05 PM