blood transfusion Flashcards
What does a blood collection bag contain?
- 70-100mL citrate anticoagulant solution
- dextrose to preserve viability of RBCs
- 400 - 450mL of blood
STORED AT 2-6C
What physiological changes will occur during blood storage?
- gradual decrease in % of viable RBCs
- platelets drop to zero rapidly
- coagulation factors V & XIII markedly drops
- potassium content increases due to RBC breakdown leading to hyperkalemia
What is shown on a blood bag?
- blood group
- Rh
- expiry date
- date of collection
- components inside
Which patients should receive only packed red cells?
- ANEMIC
- ELDERLY
- CARDIAC patients
- RENAL patients
to increase hemoglobin content without overloading circulation
What is a useful method of correcting hemophilia & liver cell failure?
FRESH FROZEN PLASMA
- stored at -40
- good source of all the coagulation factors
What are the components of fresh plasma?
coagulation factors & platelets
given in hypoproteinemia
What is a useful method of managing thrombocytopenia?
giving PLATELET CONCENTRATES
- should be freshly prepared
- increases platelet number by 10 000 to 15 000
How is cryoprecipitate prepared?
- prepared from fresh frozen plasma
- stored at -40C
- rich in factor VIII & fibrinogen
What are the indications for a blood transfusion?
- decreased blood volume (hemorrhage)
- decreased RBCs (anemia)
- decreased WBCs (leucopenia, agranulocytosis, & severe infections)
- decreased platelets (thrombocytopenic purpura)
- decreased plasma proteins (burns, ascites, hepatic dysfunction)
- decreased coagulation factors (hemophilia A&B)
What is the most common complication of a blood transfusion?
PYROGENIC REACTION
- chills & fever
- headache, nausea, & vomiting
STOP TRANSFUSION + IV ANTIHISTAMINES + HYDROCORTISONE + ANTIPYRETIC
What are the causes of a pyrogenic reaction in blood transfusions?
- minor bacterial contamination
- donor’s white blood cells or platelets
- pyrogens in transfusion apparatus
if patient has >38C fever do not give blood transfusion
What complication of blood transfusion is more liable to occur in elderly patients?
CONGESTIVE CARDIAC FAILURE due to volume overload
- could occur in cardiac & renal patients as well
- transfuse packed red cells instead
STOP TRANSFUSION + GIVE DIURETICS + DIGOXIN
When should blood transfusions be given?
early in the morning
What causes an allergic reaction to a blood transfusion?
- due to recipient’s response to allergens in donor’s blood
- common in patients who received many transfusions in the past
STOP TRANSFUSION + IV ANTIHISTAMINES & HYDROCORTISONE
What is the cause of hemolytic reactions?
incompatible blood transfusion
What does a hemolytic reaction present as & when?
- presents after transfusion of less than 50mL fever, chills chest pain dyspnea pain in flanks
serious life threatening condition
What will examining a person getting a hemolytic reactions reveal?
tachycardia
hypotension
hemoglobinuria
jaundice & acute renal failure due to acute tubular necrosis
How does a hemolytic reaction present in an anesthetized patient?
sudden tachycardia
hypotension
bleeding tendency
NEVER GIVE BLOOD UNDER ANESTHESIA
how should a hemolytic reaction be managed?
- stop infusion immediately
- send donor’s blood & sample of patients blood for repeat typing
- correct shock by infusion of crystalloid solution & i.v corticosteroids
- foley’s catheter check urine output
- mannitol may be needed (osmotic diuretic)
- dialysis if acute renal failure occurs
What are the most common infection transmitted through blood transfusions?
Hepatitis B or C
AIDS (HIV)
Malaria (only by RBCs)
septicemia if blood is allowed to warm
What causes hyperkalemia during a blood transfusion?
- prolonged storage of blood leading to progressive blood loss of potassium from erythrocytes into plasma
may produce cardiac arrhythmias or arrest
escape of air into the circulation during a blood transfusion will lead to?
air embolism
When does citrate intoxication occur during a blood transfusion?
- excess citrate if patient takes more than 1 unit of blood
What does citrate intoxication lead to & how is it managed?
- hypocalcemia
- tetany
- augments effects of hyperkalemia on myocardium
GIVE 10mL of 10% calcium gluconate for each 2 units of blood
what are the complications of MASSIVE blood transfusions?
transfusion of 2500ml of blood at once or 5000ml over 24hrs
- hypothermia
- reduced cardiac, hepatic & renal functions
- difficult O2 delivery
- impaired blood coagulation
- citrate toxicity (hypocalcemia)
- hyperkalemia
- volume overload
- deficient oxygen transport
- thrombocytopenia & coagulation failure (due to dilution of clotting factors & platelets)
- pulmonary insufficiency (multiple small emboli produced by platelet aggregations & cellular debris in aged blood)
What are substitutes for blood?
HUMAN ALBUMIN 4.5% (plasma expander)
- no risk of hepatitis transmission
DEXTRANS (improves plasma volume)
- improve plasma volumes
- low molecular weight dextran
- high molecular weight dextran (less effective but long acting)
- Gelatin
What precautions should be made before giving dextrans?
- blood samples for blood group & cross matching because it interferes with rouleaux formations of red cells
- interfere with platelet function so it may precipitate abnormal bleeding
- total volume of dextrans should not exceed 1000mL
What are different types of blood given in transfusions?
AUTOLOGOUS BLOOD TRANSFUSION
- from same patient to himself
- in elective surgery
RECYCLED BLOOD
- blood sucked through sterile system & filtered & reused again in patient
ARTIFICIAL BLOOD
- Perfluorocarbon (Fluosoleda): synthetic oxygen carrier
- Stroma free haemoglobin
ERYTHROPOIETIN
- injection 1000-3500 units preoperatively
- increase RBC count
- used in chronic renal failure patient who are on hemodialysis
- given twice weekly but costly
