Week 3 - Online transfusion reaction - Allergic (treatment), IgA deficiency,ABO, Febrile,Fluid overload, TRALI Flashcards
Scenario 1 A patient is receiving a transfusion for anaemia cause by acute myeloid leukaemia. This is her fourth transfusion. Within a few minutes of transfusion the patient develops a shortness of breath and an urticarial rash. When you go to examine here you notice a wheeze. The patient has SOB, urticaria and wheeze. WHat type of reaction is she having here? WHat is it mediated by?
The patient is having an allergic reaction Type 1 Hypersensitivity reaction mediate by IgE - immediate response
What are the 4 types of hypersensitivity reaction?
- Type 1 - Acute/Immediate - IgE mediated
- Type 2 -Cytotoxic - mediated by IgM and IgG - usually autoimmune disease
- Type 3 - Immune complex mediated - IgG mostly
- Type 4 - Delayed type hypersensitivity reactions - Tcell mediated
The binding of IgE to tissue mast cells and eosinophils/basiophils results in histamine release How does histamine cause the shortness of breath and wheezing?
Histamine causes bronchial smooth muscle contraction therefore the shortness of breath and wheezing
How does a type 1 hypersensitivity reaction cause an urticarial rash?
The histamine acts especially on H1 receptors in the capillaries The activation of these receptors leads to contraction of the endothelial cells causing separation allows fluid and protein plasma to enter the perivascular tissue
If wanting to manage a mild allergic reaction resulting in urticaria and itch, what can be given? if the reaction is severe what is required?
Can give anti-histamines eg chlorphenamine which is an H1-receptor antagonist so histamine cannot bind here
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* Lie patient flat - ensures blood reaches the brain even in low BP by reducing effect of gravity * Adrenaline - aim is to increase cerebral and cardiac cirucation - causes peripheral vasoconstriction and increases CO, also acts on beta receptors in lung to cause bronchodilation * Chlorampheniramine - binds to H1 receptor to prevent histamine effects * Salbutamol -beta agonists - bronchodilations * Corticosteroids - reduces inflammatory response by reducing action of leukotirenes
What is the order that is carried out in a patient with severe allergic reaction to a blood transfusion?
- Lie patient flat 2. Administer adrenaline - cardiac and cerebral perfusion as well as bronchodilation 3. Administer chlorampheniramine - H1 receptor antagonist blocking effects of hsitamine 4. Administer salbutomal - beta agonist in airways to cause bronchodilation 5. Administer corticosteroids- aims to reduce inflammatory response by preventing action of leukotrienes
What do you want to know about the patients medical history to understand and investigate the cause of her reaction? What immunoglobulin deficiency can increase risk of allergic reaction?
Understand if they have any allergies to eg peanuts See if the patient has an igA deficiency and therefore she could have formed antibodies to any IgA antibodies in the incoming blood
Scenario 2 A patient is receiving a transfusion for anaemia cause by chronic myeloid leukaemia. This is her fourth transfusion. Within a few minutes of transfusion, the patient develops back pains and rigors and fever. The nurse checks her urine and finds ++ of blood in it.
The patient has been transfused an incompatible blood type - probably an ABO incompatibility due to the speed Acute immediate haemolytic transfusion reaction
What type of hypersensitivity reaction is ABO incompatibility?
This is a type II hypersensitivty reaction - the IgM antibody binds to the the foreign cells that express a foreign cell atigen (ie Group A patient being given Group B blood cells) resulting in activation of the complement, also kinin pathway and coagulation pathway
What type of haemolysis occurs in ABO incompatibility? What does it cause the release of?
Intravascular haemolysis Leading to haemaglobinaemia which is released in the kidneys as haemaglobinuria Also get haemosiderinuria And methaemalbuminaemia
What causes the temperature rise in acute transfusion reactions?
The release of cytokines as part of the hypersensitivity response causes the increase in temp
Why might a person have febrile non-haemolytic anaemia?
This is because the person may be reacting to the white cells in the blood rather than the red cells - this is much less common now since the universal filtration of red cells to remove any white cells after donation
How would you manage a person if they began to potentially react to transfusion with temperature like symptoms?
Stop the transfusion Ensure the patient is the correct patient with the correct blood being given ABCDE the talking patient Consider giving paracetamol for the increase in temp and then continue the transfusion at a slower rate Monitor closely
Scenario 3 A patient is receiving a transfusion for anaemia cause by chronic myeloid leukaemia. This is her fourth transfusion. The patient complains of feeling short of breath halfway through the transfusion. The nurse notes a drop in BP but she has remained afebrile and doesnt have any pain Shortness of breath. Afebrile. Drop in BP. WHat might this patient have?
This patient is likely to have a fluid overload response to the transfusion Usually TACO (transfusion associated circulatory overload) is associated with hyertension
