Transfusion consideration and blood product administration Flashcards
What is the primary goal when considering red cell transfusions?
The primary goal of red cell transfusions is to increase the oxygen-carrying capacity of the patient in situations such as anemia, acute hemorrhage, or pending procedures where augmented oxygen delivery is beneficial.
How does 2-3 DPG influence oxygen release at the tissues?
Higher levels of 2-3 DPG result in the more readily release of oxygen at the tissues for a given partial pressure, thereby increasing tissue oxygenation.
How is cardiac output increased to maximize oxygen delivery during red cell transfusions?
Cardiac output is increased by stronger myocardial contractions (positive inotropy), reducing afterload, increasing preload, and the loss of erythrocytes, reducing blood viscosity.
What are the revised red cell transfusion triggers according to the Association for the Advancement of Blood and Biotherapies?
For haemodynamically stable patients, a trigger is a hemoglobin value of 7 g/dL (PCV ≈ 21%), and for patients with existing cardiovascular disease, a trigger is a hemoglobin value of 8 g/dL (PCV ≈ 24%).
What is the purpose of the ADCAS in red cell transfusion decision-making?
ADCAS provides an objective, standardized method for evaluating anaemic dogs, supporting red cell transfusion decisions based on a patient’s score.
At what percentage of blood volume loss is a transfusion usually necessary?
A transfusion is usually necessary when blood loss reaches 30-40% of the patient’s blood volume.
How might early and mild hemorrhage be managed without red cell replacement?
Crystalloids can be used to increase intravascular volume and restore normotension, allowing compensatory mechanisms to correct the red cell deficit.
What defines a massive transfusion, and what complications can it cause?
Massive transfusion involves RBC transfusion equal to or greater than the patient’s total blood volume in 24 hours. Complications include coagulopathy, thrombocytopenia, metabolic abnormalities, hypothermia, and citrate toxicity.
What are the purposes of transfusing plasma products?
Plasma transfusions replace deficient haemostatic proteins, provide prophylactic treatment, replace albumin, and are part of the haemorrhagic shock resuscitative strategy.
n what situations are platelet transfusions commonly used, and what count is associated with serious bleeding in humans?
Platelet transfusions are used for thrombocytopenic patients with active bleeding, prophylactically to prevent bleeding, prior to invasive procedures, and in managing haemorrhagic shock. Serious bleeding in humans is unlikely if the platelet count is 10,000/µl or higher.
What is the preferred route for red cell transfusions in almost all patients?
Intravenous is the preferred route for red cell transfusions due to its quick and effective nature, with both peripheral and central options. A minimum 25G needle is recommended to prevent damage, and blood products should not be mixed with other IV solutions.
In what situations is intraosseous transfusion utilized, and where are the common sites for insertion?
Intraosseous transfusion is used when IV placement is challenging, such as in small/neonatal patients or those with collapsed vasculature. The common insertion sites include the trochanteric fossa of the femur or the tibia and iliac crest. It allows rapid absorption, with 90% of transfused cells in circulation within 5 minutes.
When is intraperitoneal transfusion considered, and what is a notable drawback?
Intraperitoneal transfusion is considered in cases where IV and intraosseous access has failed. However, it has a slow rate of absorption for red blood cells, with only 50% circulating within 24 hours and 70% within 48-72 hours. It is reserved for specific cases due to the slow absorption and the shorter life span of transfused red cells.
What are the essential checks to maximize recipient safety before preparing a blood product for administration?
Unit checks involve two-person verification, checking written authorization, visually inspecting for damage, leakage, or abnormalities, confirming the correct blood product and blood type, and checking patient identification. Visual inspection includes looking for discolouration, cloudiness, clots, or particulate matter.
What are the potential reasons for clots in a red cell unit, and why is it crucial to identify them?
Clots in a unit can result from bacterial contamination or inadequate mixing during collection. Bacterial contamination may not cause visible changes, making detection challenging. Administering an expired, damaged, or abnormal unit can harm the recipient, emphasizing the importance of thorough checks.
What are the guidelines for releasing red cell products exposed to temperature changes during storage?
Red cell products exposed to a core temperature change not exceeding 10 °C and not less than 1 °C during storage may be released for transfusion, provided it occurred once, lasted less than five hours, and is documented. Fresh frozen plasma exposed to room temperature for up to four hours or refrigerated for up to twenty-four hours may be released.
How does haemolysis contribute to storage lesions, and what is the maximum permitted haemolysis in human red cell units?
Haemolysis occurs in stored red cell units, releasing haemoglobin and contributing to storage lesions. The maximum permitted haemolysis in human red cell units is 0.8% in Europe and 1% in America. Haemolysis testing involves measuring free haemoglobin in a sample obtained from the unit. The released haemoglobin can lead to adverse reactions and renal injury in recipients.
What consequences can arise from administering red cell units with high levels of haemolysis, and how is haemolysis checked in stored units?
Administering red cell units with high haemolysis levels can lead to severe acute haemolytic transfusion reactions. Haemolysis is checked by measuring free haemoglobin in a sample obtained from the unit, and the percentage haemolysis is estimated using the PCV and two haemoglobin values.
What are the potential sources of bacterial contamination in blood products?
: Bacterial contamination can arise from unsterile collection systems, the donor’s blood, the donor’s skin, and the environment during collection, processing, and preparation. Asymptomatic bacterial infections leading to donor bacteraemia, especially from the donor’s skin flora, are common sources.
What temperature range is conducive to the reproduction of psychrophilic bacteria in stored red cell units, and why is bacterial contamination less problematic in frozen plasma and cryo products?
Psychrophilic bacteria can reproduce in stored red cell units at temperatures between 1-6 °C. Frozen plasma and cryo products are less prone to bacterial contamination as they are stored frozen, reducing the risk of harmful bacterial proliferation.
What is the maximum time a blood product can be at room temperature once the unit is breached, and why is this limit crucial?
The maximum time at room temperature for a breached blood product is four hours. This limit is to minimize bacterial replication, reducing the risk of harmful bacterial population levels. The cellular debris and fibrin strands in stored blood products can provide a culture platform.
Why is a dedicated peripheral line preferred for blood product administration, and what precautions should be taken when using an existing intravenous catheter?
A dedicated peripheral line is preferred to minimize the risk of septic reactions. When using an existing catheter, it should be checked for phlebitis, correct placement confirmed, and the site should be clean. Correct technique involves meticulous asepsis, using disinfectant caps, and flushing the catheter with sterile saline.
