A transfusion should be stopped immediately whenever a transfusion reaction is suspected and an investigation performed according to institution procedures. Should there be an issue, where after investigation, the reaction needs to be reported to United Blood Services due to an attribute specific to the donor or the processing of the blood product (e.g., potential bacterial contamination of the component), report the information using the Report of Transfusion Adverse Reaction form (BS 962). The following tables list symptoms associated with types of reactions.

Immediate Transfusion Reactions
Type of Reaction Definition Symptoms
Transfusion associated sepsis Bacterial contamination of transfused blood • Shaking chills
• Hemoglobinuria
• Oliguria/anuria
• Fever over 39C (or 102F), or rise of 2C or 3.5F over pretransfusion values
• Heart rate 120/min, or rise of 40/min from pretransfusion values
• Drop or rise in blood pressure of 30/mm Hg over pretransfusion values
Febrile non-hemolytic reactions Temperature increase of >1C associated with transfusion and without any other explanation • Temperature increase ≥ 1C or 2F
• Chills
• Rigors
Immune-mediated hemolysis Transfused RBCs interact with pre-formed antibodies in recipient • Fever, (rise of ≥1C or 2F)
• Chills
• Pain in chest, lower back, abdomen, and/or at infusion site
• Hypotension (decrease by ≥ 20 mmHg)
• Nausea
• Flushing
• Dyspnea
• Hemoglobinemia
• Hemoglobinuria
• Bilirubinemia/Billirubinuria
• Oliguria/Anuria
• Acute pancreatitis
• Shock
• Generalized bleeding (DIC)

Non immune-mediated hemolysis

Red cells undergo hemolysis due to:

1. Temperature related damage due to
• Improper storage or shipping temperatures
• Malfunctioning or improper use of blood warmers (use of microwave ovens or hot water baths)

2. Mechanical hemolysis due to oller pumps, pressure infusion pumps, pressure cuffs

3. Addition of drugs or hypotonic solutions to blood component or IV solutions

• May present with symptoms similar to immune-mediated hemolysis
Urticaria (Hives) Mid allergic reaction to transfusion • Generalized rash, erythematous macular eruption
• Hives
• Itching
• Usually without fever
Anaphylactic reactions (occur after infusion of only a few mL of blood component) Severe allergic reaction to transfusion in which there are systemic symptoms • Coughing, bronchospasm, respiratory distress
• Vascular instability, hypotension
• Nausea, abdominal cramps, vomiting
• Diarrhea
• Shock
Air Embolism Air allowed into infusion equipment or blood in open system infused under pressure causing air bubble • Cough
• Dyspnea
• Chest pain
• Shock
Transfusion-related acute lung injury (TRALI)

(Link to more information on TRALI)
A new episode of acute lung injury (ALI) that occurs during or within 6 hours of a completed transfusion • Acute respiratory insufficiency in the absence of evidence of circulatory overload
• No left atrial hypertension
• Acute onset
• Hypoxemia (capillary oxygen decreases to <90% on room air)
• Bilateral infiltrates on frontal chest x-ray
• No other evidence of cardiac failure or a cause for respiratory failure
Transfusion Associated Circulatory Overload (TACO) Acute pulmonary edema due to volume overload • Dyspnea, orthopnea
• Severe headache
• Hypertension, tachycardia
• Congestive heart failure
• Acute pulmonary edema
Metabolic reactions Metabolic derangements resulting from large-volume transfusions • Citrate toxicity
• Hyperkalemia
• Hypocalcimia
• Hypothermia
• Respiratory alkalosis
Hypothermia Depressed body temperature resulting from rapid infusion of large volumes of cold blood components • Hypothermia
• Cardiac arrhythmia or arrest
• Exacerbation of underlying coagulopathy
Delayed Transfusion Reactions
Type of Reaction Definition Symptoms

Alloimmunization to red cell antigens (usually an anamnestic immune response that occurs from 3-10 days post-transfusion)

Risk: 1-1.6% per donor unit

Development of newly formed antibodies to red cell antigens • Fever
• Decreasing hemoglobin
• Mild jaundice
• Signs of hemolysis in about 20-35% of sensitized recipients

Alloimmunization to leukocyte antigens

Occurs in patients receiving repeated platelet transfusions and women with for > 4 pregnancies

Development of antibodies to leukocyte (HLA) antigens • Signs of febrile non-hemolytic transfusion reactions
Refractoriness to platelet transfusion Rapid clearance of transfused platelets due to HLA sensitization or other clinical factors • Poor incremental increase in platelet count after a suitable dose of platelets
Post-transfusion purpura
(usually occurs > 1 week after transfusion)
Abrupt onset of severe thrombocytopenia an average of 9 days post transfusion (range 1-24 days) • Precipitous fall in platelet count
• Generalized purpura

Iron overload

Occurs in chronically transfused patients (> 20 units per lifetime)

Accumulation of iron and no physiologic means of excretion • Interference with heart, liver or endocrine gland function
• Hepatic failure
• Cardiac toxicity
Acute Transfusion-associated Graft-vs-Host disease Immunologic complication caused by engraftment and proliferation of donor lymphocytes in a susceptible host • Fever
• Erythroderma, often starting on palms, soles, earlobes, and face, ranging from edema to full blistering
• Enterocolitis
Additional Information Relating to Transfusion Related Acute Lung Injury (TRALI)

TRALI is a syndrome characterized by bilateral pulmonary edema, hypoxia, tachycardia, fever, hypotension and cyanosis in the setting of transfusion of plasma containing blood components, always within 1-6 hours and usually within 2 hours. Normal central venous and pulmonary wedge pressures are consistent with TRALI.

TRALI is a diagnosis of exclusion. Other causes of respiratory distress and pulmonary edema in a transfusion setting such as myocardial infarction, circulatory overload or bacterial infection should be ruled out.

Definition of TRALI:

• ALI:


  • Acute onset (During or within 6 hours of transfusion)
  • Hypoxemia:
    ο PaO2 /FiO2 ≤ 300,
    ο Or SpO2 < 90% on room air
  • Bilateral infiltrate on chest x-ray
  • No left atrial hypertension (i.e., circulatory overload)
• No preexisting ALI
• No temporal relationship to an alternate risk factor for ALI

Suggested Prerequisites For Performing A Laboratory Workup:

  • A laboratory workup of a TRALI case is expensive.
  • Donors may experience anxiety and/or concern that their blood donation may have resulted in harm to a recipient.
  • For these reasons, the transfusing institution has the obligation of providing complete information on the TRALI case to the blood center.
  • Information to be provided should include:
    • Sufficient clinical data to confirm the TRALI diagnosis and to exclude other causes of ALI.
    • The results of any laboratory tests performed to rule out other transfusion reactions.
    • Data as to the storage age of the transfused components for evaluating the neutrophil priming hypothesis of TRALI pathogenesis.

Suggested Laboratory Investigations
Patient: • White blood cell count
• B-natriuretic peptides (BNP)
• Type for HLA Class I & Class II antigens
• Priming activity
Blood component: • Priming activity
Donors (Done on all
donors or on a sequential testing algorithm):
• Screen samples for HLA Class I & Class II antibodies. (If HLA antibody identified, type for specificity.)
• Screen donors for neutrophil antibodies. (If HNA antibody identified, type for specificity.)
Patient/Donor(s): • A cross-match between donor serum a patient white blood cells
Transfusion Associated Infections

The risk of acquiring an infectious disease through blood transfusion has not been totally eliminated even though the level and sensitivity of testing today makes transfusion very safe. Physicians/hospital staff should report all instances when an infectious disease is reasonably likely to have been transmitted by a blood transfusion. 

The requirements for investigating Transfusion Associated Infections (TAI) are found in the Code of Federal Regulations, Title 21, Section 606.170, and the AABB Standards.

The most commonly investigated infectious diseases are: retrovisruses, hepatitis viruses, West Nile virus, malaria, babesiosis, and Chagas Disease.

The hospital’s investigation includes:

  • Complete medical history
  • Clinical laboratory data
  • History of known risk factors for the reported infection

The objectives of blood center investigations of TAI are:

  • Quarantine of additional infectious components
  • Deferral of an “unsafe” donor
  • Notification of the donor and other recipients of the donor’s blood
  • Process improvements

In January of each year, United Blood Services sends the “Letter to Encourage Reporting of TAI” to transfusion facilities served by the center. It is the responsibility of the transfusion facility to have monitoring and identification mechanisms and policies in place to recognize potential TAI related to transfusion and to report them to the blood center.

If a possible TAI is identified, complete a Report of Transfusion Associated Infection form (BS 314) and submit to your blood center. The center will forward the form to the Medical Affairs department at our national office for investigation and evaluation. A follow-up letter(s) is sent to the transfusion facility to allow the facility to notify the recipient’s attending physician of the results of the investigation.


Blood Systems and its divisions and affiliates provide comprehensive transfusion medicine services. These include: BioCARE • Blood Services (Blood Centers of the Pacific, BloodSource, Bonfils Blood Center, Community Blood Services, Inland Northwest Blood Center, The Institute for Transfusion Medicine, Lifeblood, LifeShare, LifeStream, United Blood Services) • Blood Systems Laboratories • Blood Systems Research Institute • Creative Testing Solutions