Blood loss and transfusion Flashcards
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
What is oxyglobin?
Chemically stabilized bovine hemoglobin
What is oxyglobin used for?
Used to treat anemia in dogs
What are some side effects of using oxyglobin?
May cause circulatory overload; can cause an allergic reaction if given repeatedly; can temporarily cause yellow discoloration of the skin, mucous membranes, and sclera
