16. Blood Products

Transfusion Guidelines at UCSF

  • See online UCSF Laboratory Manual for up to date details regarding transfusion thresholds for platelets, FFP and cryoprecipitate and indications for CMV seronegative, irradiated or washed products.

Pre-medication

Pre-medicating is not always necessary and diphenhydramine (Benadryl) should be avoided in the elderly. In patients who get mild symptoms (fever, mild rash) with transfusions, consider Tylenol 650 mg PO/PR and Benadryl 25 mg PO/IV.

Packed Red Blood Cells (pRBC)

  • All blood products at UCSF are leukoreduced (WBCs removed). Most of the plasma is removed from a pRBC unit. One unit should raise the hematocrit by about 3 points or the hemoglobin by 1 g/dL. Volume per unit = 200-250 ml.
  • Evidence from the TRICC trial suggests a transfusion threshold of 7 gm/dl hemoglobin for most patients.
  • In active bleeding, higher goals should be used and may be considered for patients with symptoms of anemia or cardiac ischemia/congestive heart failure.
  • CMV seronegative pRBCs are required for CMV-seronegative patients with immunosuppression (including patients with BMT, hematologic malignancies) and CMV-seronegative pregnant patients.
  • Irradiated pRBCs are required for heavily immunosuppressed patients (e.g. bone marrow transplant and donor leukocyte infusion recipients) and patients undergoing myeloablative or lymphotoxic chemotherapy.
  • Washed pRBCs may be required for patients with severe allergic reactions.

Platelets

  • Only apheresis leukoreduced platelets are available at UCSF. One dose of apheresis platelets (equivalent to a 6-pack) raises platelet count by 30,000/μL-50,000/μL.
  • CMV seronegative and irradiated platelets are required for heavily immunosuppressed patients (e.g. bone marrow transplant recipients) and patients undergoing myeloablative or lymphotoxic chemotherapy.
  • Transfusion parameters:
    • Platelets <10,000/μL for non-bleeding, normal risk patient.
    • Platelets <20,000/μL for patient with mucositis or fever.
    • Platelets <50,000/μL for patients with active bleeding, pre-op, or peri-procedure.
    • Platelets <75,000/μL for uremic bleeding patients.
    • Platelets <100,000/μL for intracranial, spinal, ocular, airway or life-threatening bleed.
    • Patients with drug-induced, uremic or inherited platelet function disorders who are at risk of bleeding may benefit from transfusion of qualitatively normal platelets.
  • Chronically transfused patients may develop HLA alloantibodies and become refractory to platelet transfusions. If concerned, obtain 15 min-1 hour post transfusion platelet counts and contact the Blood Bank Resident to arrange for platelet crossmatch testing; takes 1-2 days for cross-matched platelets to become available.
  • Volume reduced platelets are indicated for patients with recurrent or severe allergic reactions.

Fresh Frozen Plasma (FFP)

  • An elevated PT is frequently encountered in end-stage liver disease. Prophylactic FFP infusions are not recommended when a patient is not bleeding.
  • FFP can be considered when patients have active bleeding or prior to planned procedures when INR is greater than 1.6-2.
  • FFP may be used for the urgent reversal of warfarin toxicity in patients with major bleeding or those at a high risk of bleeding.   

Cryoprecipitate

  • Contains factor VIII, von Willebrand factor, fibrinogen and factor XIII.
  • Indications include patients with fibrinogen levels ≤100 mg/dL who are bleeding or at high risk of bleeding (e.g. active DIC), qualitative fibrinogen deficits (e.g. acquired dysfibrinogenemia associated with liver disease), factor XIII deficiency.
  • Use of cryoprecipitate in patients with hemophilia A (factor VIII deficiency) and von Willebrand disease has been supplanted by the use of specific factor products that are safer and more efficacious.
  • One unit of cryoprecipitate contains 200-350 mg fibrinogen. Available in pools of 5 units. One unit raises fibrinogen 5-10 mg/dL. One adult dose = 10 units (~200 ml).

Massive Transfusion Protocol

See online UCSF/SFGH Laboratory Manual for up to date details regarding policies.

  • Historically, massive transfusion defined as 10 units of pRBCs in 24 hours. Now, often defined as massive hemorrhage accompanied by hypovolemic shock and/or metabolic acidosis requiring >4 units of blood during the first hour of resuscitation.
  • When the massive transfusion protocol is activated, the blood bank is typically signaled to rapidly release 4 units of type specific but uncrossmatched pRBCs, 4 units of FFP, and one unit of platelets. Additional products available urgently upon request.
  • Blood products should be ready <10 minutes and should be picked up by member of the team.

 

Churchill WH.  Transfusion therapy. In: Scientific American Medicine.  Edited by Federman D.  New York: Scientific American, 1999.

Hebert PC, Wells G, Blajchman MA et al.  A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group. N Engl J Med. 1999 340(6):409-17.