RBC | Platelets
| FFP |
Practice guidelines for blood component therapy. -
Anesthesiology 1996 Mar; 84(3):732-47
A report by the American Society of Anesthesiologists Task
Force on Blood Component Therapy.
Red blood cell transfusions
The transfusion of one unit of whole blood or RBCs increases the hematocrit
by approximately 3%, or the hemoglobin concentration by 1 g/dL,
in a 70-kg nonbleeding adult.
The task force concludes that for RBS transfusion
RBC transfusion is rarely indicated when the hemoglobin concentration is
greater than 10 g/dL and is almost always indicated when it is less than
6 g/dL, especially when the anemia is acute;
the determination of whether intermediate hemoglobin concentrations (6-10
g/dL) justify or require RBC transfusion should be based on the patient's
risk for complications of inadequate oxygenation;
the use of a single hemoglobin "trigger" for all patients and other approaches
that fail to consider all important physiologic and surgical factors affecting
oxygenation are not recommended;
when appropriate, preoperative autologous blood donation, intraoperative
and postoperative blood recovery, acute normovolemic hemodilution, and measures
to decrease blood loss (deliberate hypotension and pharmacologic agents)
may be beneficial; and
the indications for transfusion of autologous RBCs may be more liberal than
for allogeneic RBCs because of the lower (but still significant) risks associated
with the former.
Preparation and administration of RBCs
Type-and-screen the recipient's RBCs for the A, B, and D (Rh) antigen
and also the recipient's serum for antibodies against other RBC antigens.
Cross-matching tests the patient's serum for antibodies against antigens
on the donor's RBCs and is performed prior to dispensing a specific unit
of blood for a patient.
Leukocyte-depleting (leukopoor) filters remove 99.9% of WBCs from
blood products and are recommended in the following circumstances:
(a) in patients who have had prior nonhemolytic febrile transfusion reactions
not responsive to acetaminophen and diphenhydramine;
(b) in patients undergoing RBC exchange transfusions;
(c) in patients in whom cross-match incompatibilities are identified; and
(d) to prevent CMV infection in patients who require CMV-negative blood products
that are unavailable.
Leukocyte-depleting filters may help also to decrease the risk of platelet
alloimmunization ( Ann Intern Med 117:151, 1992).
Irradiation of blood products eliminates immunologically competent
lymphocytes and is recommended for immunocompromised bone marrow or organ
transplant recipients or in any patient receiving directed donations from
HLA-matched donors or first-degree relatives.
Washed RBCs should be considered in patients in whom plasma proteins
may cause a serious reaction (e.g., IgA-deficient recipients or in patients
with paroxysmal nocturnal hemoglobinuria).
CMV-negative blood products are indicated in immunocompromised bone
marrow or organ transplant recipients who are CMV-antibody-negative.
Premedication with acetaminophen and diphenhydramine, 25-50 mg PO or IV,
should be used in patients who have developed previous nonhemolytic transfusion
reactions. Occasionally, glucocorticoids (e.g., hydrocortisone, 50-100 mg
IV) also will provide benefit.
Administration must include careful patient and blood-product identification
procedures to avoid mishandling errors. The IV catheter should be at least
18 gauge to allow adequate flow. All blood products not leukocyte-depleted
should be administered through a 170- to 260-mum "standard" filter to prevent
infusion of macroaggregates, fibrin, and debris. Only 0.9% NaCl should be
used with blood components to prevent cell lysis. Patients should be observed
for the first 5-10 minutes of each transfusion for adverse side effects and
at regular intervals thereafter. Each unit of blood should be administered
within 4 hours.
The magnitude of increased platelt count is variable and is influenced by
the release of stored platelets from the spleen and peripheral platelet
destruction. Transfusion of one platelet concentrate will increase the
platelet count by approximately 5-10 x 1,000/mc1 in the average adult.
The usual therapeutic dose is one platelet concentrate
per 10 kg body weight. Single-donor platelets obtained by apheresis
are the equivalent of approximately six platelet concentrates. Patients
repeatedly transfused over a prolonged period may become alloimmunized and
refractory to platelet transfusion. In such patients, human leukocyte
antigen-matched or crossmatched platelets may be required. The platelet
count at which surgical and obstetric patients are likely to experience increased
bleeding is unknown.
In nonsurgical patients, spontaneous bleeding is uncommon with platelet counts
greater than 20 x 1,000/mcl and some studies suggest low complication rates
in surgical patients with thrombocytopenia. Performance of paracentesis and
thoracentesis was not associated with increased bleeding in patients with
platelet counts of 50-99 x 1,000/mcl.
The task force concludes that for platelet transfusion
prophylactic platelet transfusion is ineffective and rarely indicated when
thrombocytopenia is due to increased platelet destruction (e.g., idiopathic
prophylactic platelet transfusion is rarely indicated in surgical patients
with thrombocytopenia due to decreased platelet production when the platelet
count is greater than 100 x 1,000/mcl and is usually indicated when the count
is below 50 x 1,000/mcl . The determination of whether patients with intermediate
platelet counts (50-100x 1,000/mcl ) require therapy should be based on the
risk of bleeding;
surgical and obstetric patients with microvascular bleeding usually require
platelet transfusion if the platelet count is less than 50 x 1,000/mcl and
rarely require therapy if it is greater than 100 x 1,000/mcl . With intermediate
platelet counts (50-100 x 1,000/mcl ), the determination should be based
on the patient's risk for more significant bleeding;
vaginal deliveries or operative procedures ordinarily associated with
insignificant blood loss may be undertaken in patients with platelet counts
less than 50 x 1,000/mcl ; and
platelet transfusion may be indicated despite an apparently adequate platelet
count if there is known platelet dysfunction and microvascular bleeding.
Platelet transfusion guidelines
Transfusion of a fresh, single-donor apheresis unit should produce the same
increment in platelet count (approximately 30,000/mul) in a patient with
a pure production problem as that of six stored units derived from whole
blood. Platelets are infused IV over 30 minutes. Premedication is unnecessary.
Transfusion threshold. Approximately 5 × 1010 platelets
(roughly the content of a single apheresis unit) are needed each day to satisfy
basal requirements (to saturate the splenic reservoir and to repair sites
of endothelial damage).
Each patient has a threshold at which the perceived risk of spontaneous
hemorrhage warrants prophylactic platelet transfusion. Patients with chronic
thrombocytopenia generally do not require platelet transfusion unless they
develop overt bleeding or a superimposed coagulopathy. A rational guideline
for asymptomatic acutely thrombocytopenic patients is to measure the platelet
count once daily and to transfuse a single product for a platelet count of
less than 10,000/mul.
Prophylactic transfusion is reasonable for patients to keep count
10,000-20,000/mul if a minor invasive procedure is performed , if a coagulopathy
or minor mucosal bleeding (minor epistaxis, occult GI bleeding, petechiae)
50,000/mul if a major invasive procedure is performed .
100,000/mul for high-risk surgery (e.g., neurosurgery, ophthalmic
surgery, cardiopulmonary bypass) .
Platelet transfusion thresholds change if there is evidence of bleeding.
Platelet refractoriness. This condition develops in approximately half of
multiply transfused patients. It can be documented by measuring the platelet
count before and 60 minutes after transfusion. An increment of less than
5000/mul after one apheresis unit or six random-donor units is an indication
of refractoriness. The mechanism is development of alloantibodies, usually
directed at donor lupus anticoagulant or ABO antigens expressed on platelets
and leukocytes. The following interventions may improve platelet increments
in alloimmunized patients: transfusion of ABO-identical platelets; use of
fresh, rather than stored platelets; use of lupus anticoagulant-matched donors
(preferably family members); and, in actively bleeding patients, administration
of IVIG (400 mg/kg qd for 5 days) prior to transfusion ( Am J Hematol 38:15,
is indicated for urgent reversal of warfarin therapy, correction of known
coagulation factor deficiencies for which specific concentrates are unavailable,
and correction of microvascular bleeding when prothrombin and partial
thromboplastin times are >1.5 times normal. It is contraindicated for
augmentation of plasma volume or albumin concentration.
The task force recommends the administration of FFP with the following
for urgent reversal of warfarin therapy;
for correction of known coagulation factor deficiencies for which specific
concentrates are unavailable;
for correction of microvascular bleeding in the presence of elevated
(>1.5 times normal) PT or PTT;
for correction of microvascular bleeding secondary to coagulation factor
deficiency in patients transfused with more than one blood volume and when
PT and PTT cannot be obtained in a timely fashion;
FFP should be given in doses calculated to achieve a minimum of 30% of plasma
factor concentration (usually achieved with administration of 10-15 ml/kg
of FFP), except for urgent reversal of warfarin anticoagulation, for
which 5-8 ml/kg of FFP usually will suffice. Four to five platelet concentrates,
one unit of single-donor apheresis platelets, or one unit of whole blood
provide a quantity of coagulation factors similar to that contained in one
unit of FFP (except for decreased, but still hemostatic, concentrations of
factors V and VIII in whole blood);and
FFP is contraindicated for augmentation of plasma volume or albumin
Cryoprecipitate, which contains factor VIII, fibrinogen, fibronectin,
von Willebrand's factor, and factor XIII, is used for the correction of inherited
and acquired coagulopathies.
One unit of cryoprecipitate per 10 kg body weight raises plasma fibrinogen
concentration by approximately 50 mg/dL in the absence of continued consumption
or massive bleeding. However, most patients with factor VIII deficiency are
treated with factor VIII concentrates, and patients with some subtypes of
von Willebrand's disease respond to administration of desmopressin acetate
(DDAVP). Similarly, coagulopathy associated with uremia can be treated with
cryoprecipitate, but DDAVP is usually the first-line therapy.
It has been observed that patients with certain inherited or acquired
coagulopathies (e.g., hemophilia A, von Willebrand's disease, hypofibrinogenemia,
disseminated intravascular coagulation, hepatic insufficiency) are at increased
risk of perioperative or peripartum bleeding. It should be considered
for patients with von Willebrand's disease unresponsive to desmopressin,
bleeding patients with von Willebrand's disease, and bleeding patients with
fibrinogen levels below 80-100 mg/dL. The task force recommends careful adherence
to proper indications for blood component therapy to reduce the risks of
The task force recommends considering the administration of cryoprecipitate
prophylaxis in nonbleeding perioperative or peripartum patients with congenital
fibrinogen deficiencies or von Willebrand's disease unresponsive to DDAVP
(whenever possible, these decisions should be made in consultation with the
bleeding patients with von Willebrand's disease, and
correction of microvascular bleeding in massively transfused patients with
fibrinogen concentrations less than 80-100 mg/dL (or when fibrinogen
concentrations cannot be measured in a timely fashion).
Factor VIII replacement. A good rule of thumb is that factor VIII
levels will increase 2% for every 1 unit/kg infused. Thus, 50 units/kg IV
bolus will raise factor VIII levels to 100%. This dosage can be followed
by 25 units/kg IV bolus q12h. Dose adjustment based on trough factor VIII
levels should be made every 1-2 days in patients with moderate to severe
hemorrhage. The recombinant products are the most expensive and may
be associated with a greater risk of inducing inhibitor formation. They should
be reserved for use in HIV-seronegative and hepatitis C virus-seronegative
or previously untreated patients.
Factor VIII Products:
Low purity: Cryoprecipitate
Intermidiate purity: Humate-P, Koate-HP, Factor VIII-SD, Proliferate-OSD
High purity: AHF-M, Alphanate, Hemophil-M, Monoclate-P, Recombinate,
Bioclate, Kogenate, Helixate
What are the current risk estimates for Transfusion-Transmitted Infection
with HIV, HTLV, HCV or HBV?
Actual transmission rates for Transfusion-Transmitted Infection may exceed
reported estimates of risk. Based on the most recent estimates, the risk
per unit of viral exposure of a transfusion recipient ranges from 0.52 (for
HIV) to 7.21 (for HBV) per million donations, with an overall risk of 10
per million units for the four viruses combined.
HIV 1 in 1,930,0002
HTLV 1 in 641,0001
HCV 1 in 1,543,0002
HBV 1 in 138,7002
1. New England Journal of Medicine 6-27-96: Retrovirus Epidemiology Donor
Study (REDS). Study focused on the likelihood that a donor would be in the
infectious window period when he/she donated, and that the unit of blood
would pass all screening tests. Actual incidence of viral exposure via
transfusion may be higher.
2. Dodd, RY. Blood Safety in the New Millenium, 2001.
See also Transfusion
Practice guidelines for blood component therapy. -
Anesthesiology 1996 Mar; 84(3):732-47
A report by the American Society of
Anesthesiologists Task Force on Blood Component Therapy.
Dambro: Griffith's 5-Minute Clinical Consult,
Rakel: Conn's Current Therapy 1999
Washington Manual of Medical Therapeutics, 29th ed.1998