Blood comprises a liquid component called plasma, in which red blood cells, white blood cells and platelets are suspended.
Plasma consists of mainly water and contains dissolved electrolytes and proteins that include albumin, which transports hormones and medicines; antibodies against infective agents; and clotting factors.
The blood components have other functions as well.
Blood transfusion is essential in healthcare, with widespread usage. It is required in managing medical conditions such as anaemia, bleeding in childbirth, cancer, etc; trauma; and medical procedures or surgical operations.
Blood is taken from a donor, tested, processed and stored until needed by another person. The transfusion process involves insertion of a plastic tube attached to a bag of blood into the recipient’s vein, with the blood entry at a rate determined by need.
There are different types of blood transfusion depending on the reason for transfusion. It may be whole blood; red blood cells which helps anaemia; platelets which helps clotting; and/or plasma, cryoprecipitate and prothrombin complex concentrate which contain large amounts of clotting factors.
Blood transfusion is life-saving for many patients. It improves outcomes, particularly when there is bleeding from the body, whether it is acute or chronic.
Yet blood transfusion is not without risks of transmission of blood borne infections and allergic reactions.
Blood transfusion is a marriage of science and altruism. Although its processes are technical, its success is entirely dependent on the generosity of the blood donors.
Safe transfusion requires the application of science to blood collection, processing, testing, and storage, as well as social mobilisation that promotes voluntary blood donation by enough numbers of healthy people who are at low risk of infections.
What patients can do
There are several questions that all patients are advised to ask doctors before agreeing to a blood transfusion.
They include, among others: Why is blood transfusion recommended; What does it involve; What are the benefits and risks; What are the side effects and what should be done if and when they occur; What types of blood or its components and how many units will be given; Are there alternatives, particularly if some/any type of blood transfusions are against one’s personal beliefs; Where and from whom can more information or second opinion be sought; and What can happen if medical advice is not followed?
There are alternatives to blood transfusion. Autologous blood transfusion involves collection of the patient’s own blood which is stored for subsequent use.
It prevents the transmission of disease, avoids transfusion reactions and is useful in planned surgical procedures.
Intra-operative blood salvage involves the collection of blood from a source of bleeding or body cavity during surgery and subsequent re-infusion into the same patient. Post-operative blood salvage involves the collection of blood from the body cavity or joint spaces and re-infusion into the same patient.
Blood transfusion is associated with side effects which all recipients need to know. Some occur during transfusion or soon after, but others are delayed.
The features of transfusion reactions include restlessness, fever, chills, rigors, changes in blood pressure, breathing problems, rashes, nausea, vomiting and pain at the infusion site, chest or abdomen.
When any of these features occur, the nurse and doctor have to be informed immediately.
When a transfusion reaction is suspected, the transfusion has to be stopped immediately. All transfusion reactions are investigated to elucidate the cause.
All the above issues should be clarified and understood before agreeing to a blood transfusion.
What providers can do
Before ordering a blood transfusion, a basic question has to be asked by the doctor, i.e. “Is blood transfusion necessary?” If so, then the principles to be adhered to are “Right blood, Right patient, Right time and Right place”.
Blood transfusion should only be recommended when there are no appropriate alternatives and the benefits outweigh the risks.
The decision to transfuse blood is a clinical one and should be based on evidence-based guidelines.
Unnecessary and inappropriate transfusions must be avoided. The patient has to be informed of the risks, benefits and alternatives to transfusion and consent must be obtained.
The identity of the patient has to be checked at every stage of the transfusion process.
Patients have to be identified by their name, identity card number and gender. In the event that there is a discrepancy between the patient identifiers and the pack containing the blood, transfusion cannot be carried out.
When the wrong blood is transfused to a patient, it is nearly always caused by human error.
Most transfusion errors are due to identification errors at the time of sourcing of blood from donors; handling of blood in the laboratory; collecting the wrong blood or component(s) from the laboratory; or transfusion to the patient.
The check between the patient’s identifiers and the labels on the blood bag is the last opportunity to avoid wrong transfusion.
The critical safety factors throughout the blood transfusion process are positive patient identification, constant monitoring, good communication and good documentation.
Underpinning these are well trained, competent and conscientious nurses and doctors.
Requests for blood transfusion outside the usual working hours and overnight blood transfusions are generally avoided if possible because of the increased risk of errors, which may lead to fatalities.
Dr Milton Lum is a past President of the Federation of Private Medical Practitioners Associations, Malaysia and the Malaysian Medical Association. The views expressed do not represent that of any organisation the writer is associated with. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.