Blood loss and transfusion Flashcards
(27 cards)
What is a blood transfusion?
The process of transferring blood or blood-based products from one individual into the circulatory system of another individual of the same species
What are the reasons for performing a blood transfusion?
Increase the Hb content of the blood; increase circulating volume; increasing plasma albumin content; provide coagulation factors; provide functional platelets
What are the different types of blood products?
Fresh whole blood (FWB; PCV ~40%), packed red cells (PCV ~70%), fresh frozen plasma (FFP), cryoprecipitate (contains coagulation factors)
When should you consider transfusion?
Acute blood loss > 20% of blood volume; > 10-15% of blood loss was peri-operative; acute anemia
True/False: clinical signs are more important than arbitrary trigger values when considering transfusion.
True
What are the clinical signs of blood loss?
Pale mucus membranes; elevated heart rate; low blood pressure; weak pulse; blood in surgical sponges and suction container
How do you estimate blood loss?
Standard surgical sponge may contain 5 mL blood; blood loss (mL) = (PCV of suctioned fluid x vol in canister (mL))/preoperative patient PCV
True/False: assuming donor PCV of 40%, 2 mL whole blood/kg BW raises PCV of recipient by 1%
True
How do you calculate how much blood to give?
Blood to be transferred (mL) = ([PCV required - PCV recipient] x blood volume of recipient (mL))/PCV of donor
What are the doses for blood transfusion?
Dogs: 10-40 mL/kg
Cats: 5-20 mL/kg
What rate should you transfuse blood at?
Start with 0.25 mL/kg for first 30 min to test for reaction; continue with rate 5-10 mL/kg/h; complete transfusion within 4 hours
True/False: when transfusing blood, it is generally ok to mix it with Ringer solution.
False. Ringer contains Ca; blood will clot again
What is the best option to use for providing coagulation factors?
Cryoprecipitate
When giving a transfusion to provide coagulation factors, how long can blood be stored?
Fresh whole blood: use within 6 hours
Fresh plasma: use within 6 hours
FFP: fresh plasma stored at -4 F for
What are some side effects of using plasma for transfusion?
May trigger an allergic reaction; may trigger immunity against blood group Ag’s (blood typing necessary)
What type of blood should be used when providing functional platelets?
Use fresh whole blood; obtain blood in plastic container; store in room temp; use within 8 hours
What are some examples of adverse transfusion reactions?
Blood type incompatibility; allergic reaction (anaphylaxis); alteration of the immune system (problems during next transfusion; neonatal isoerythrolysis in foals)
What are some side effects of transfusion?
Circulatory overload; transfusion related acute lung injury (TRALI); citrate induced hypocalcemia (tetany); sepsis (bacterial contamination); transmission of infectious diseases (FIV, FELV, hemobartonella, anaplasma, etc.)
What are the two types of blood type incompatibility reactions?
Acute reaction: life threatening; hemolysis (horses and cattle); agglutination
Slow reaction: decreased RBC life span (few days)
What are the signs of an acute blood type incompatibility reaction?
Increased HR, decreased BP, increased RR, dyspnea; tremors, vomiting, wheals, urticaria, fever; pain at injection site; hemolysis, Hb-uria, renal failure, DIC; CV collapse; less signs under anesthesia
How do you treat an acute blood type incompatibility reaction?
Stop transfusion; epinephrine IV (for anaphylactic reactions); antihistamines IV (only at the beginning); fast acting corticosteroids IV; fluids (depending on volume status); oxygen supplementation (TRALI); analgesia, etc.
True/False: blood typing and cross-matching for horses are difficult and unreliable.
True
What is major cross-matching?
Donor RBC + recipient plasma
What is minor cross-matching?
Recipient RBC + donor plasma
