Blood transfusion is the receiving of blood products into circulation via IV. The purpose is to replace lost components of blood.

• Classically, whole blood would be used, but only components of blood (e.g. RBC, WBC, plasma, clotting factors, platelets) are used in modernity
• O negative blood is considered the universal blood donor type, which is given in emergency situations and crossmatching can't be done, or where matching blood type is in short supply
• Massive transfusion protocol (aka massive trauma resuscitation, hemostatic resuscitation), when >10 units of blood are needed. Instead of crystalloid or whole blood, packed RBC's, FFP (fresh frozen plasma), and platelets are administered. Typically higher ratios of FFP and platelets are given relative to packed RBC's

• Immunological, including:
  • Febrile nonhemolytic reactions (7%), due to the release of inflammatory chemical signals released by RBC's in stored donor blood. Fever is generally short lived and Tx w/ antipyretics, and transfusions may be finished as long as acute hemolytic reaction is excluded. This is a reason for now widespread use of leukoreduction (ie. filtration of donor WBC's from RBC product units)
  • Transfusion-associated acute lung injury (0.05%), a Sx of acute respiratory distress, often associated w/ fever, non-cardiogenic pulmonary edema, and hypotension
  • Acute hemolytic reactions (0.016%, w/ 0.003% being fatal), which occur w/ transfusion of RBC's. This is due to the destruction of donor RBC's by preformed recipient antibodies. It most often occurs due to clerical errors, or improper ABO blood typing and crossmatching, resulting in a mismatch of ABO blood type between donor and recipient
  • Delayed hemolytic reactions (0.025%), are due to the same mechanisms as acute hemolytic reactions. However, the consequences are generally mild, and Pt's may be asymptomatic
  • Allergic reactions, occur when the Pt has preformed antibodies to certain chemicals in the donor blood. It doesn't require prior exposure to transfusions
  • Posttransfusion purpura, which occurs after transfusion containing platelets that express a surface protein HPA-1a
• Infection, including:
  • Higher risk of infection, particularly in those given RBC's only
  • Contamination of blood products w/ bacteria, which can result in transfusion-transmitted bacterial infection, a life-threatening infection
  • Transmission of HIV during transfusion
  • Transmission of hepatitis C via transfusion
  • Other rare transmissible infections, including hepatitis B, syphilis, Chagas disease, CMV infections (in immunocompromised Pt's), HTLV, and Babesia
• Inefficacy, where the transfusion fails to achieve it's clinical purpose, particularly significant in critical care and neonates
• Transfusion-associated volume overload, since blood products have a certain amount of volume, and particularly in Pt's w/ underlying cardiac or kidney disease
• Hypothermia, in transfusions w/ large quantites of blood products which are normally stored at cold temperatures. Core body temperature can go down as low as 32 degrees C and can produce physiologic disturbances. Prevention is w/ warming blood to ambient temperature prior to transfusions
• Inclination for bleeding, due to severe hemorraghing or transfusion inefficacy, when transfusing large amounts of RBC's. This is thought to be due to DIC, and dilution of recipient platelets and coagulation factors
• Metabolic alkalosis, in massive blood transfusions, due to breakdown of citrate stored in blood into bicarbonate
• Hypocalcemia, in massive blood transfusions, due to the complex of citrate w/ serum calcium

• Group and hold