Certified Registered Nurse Anesthesiologists (CRNAs) play vital roles in transfusion practices by managing perioperative anemia and blood loss across the perioperative continuum. In some institutions, the anesthetist may be more involved than other providers. Hence, it’s of the utmost importance for CRNAs to recognize and help manage transfusion risks and potentially fatal reactions.
In this article, we’ll cover the two leading causes of transfusion-related death as cited by the FDA: Transfusion Associated Circulatory Overload (TACO) and Transfusion Related Acute Lung Injury (TRALI).
TACO and TRALI have many similarities, making them challenging to differentiate. We’re here to help you correctly identify their symptoms, differences, and possible interventions.
What are TACO and TRALI?
TACO is a pulmonary hydrostatic edema (cardiogenic), while TRALI is a pulmonary permeability edema (noncardiogenic).
TACO often develops when a large volume of blood products is infused at a faster administration rate—though this is not the only cause. Patients with preexisting heart conditions and renal dysfunction have higher risks of developing TACO. A positive fluid balance and clinical improvement following diuresis are both indications of TACO.
TRALI, on the other hand, is an antigen and antibody reaction that occurs in the lungs. The presence of specific conditions in a patient and plasma-rich products may increase the risks of TRALI.
A medical hypothesis suggests two possible models for TRALI.
- One-hit model: A direct reaction to the transfused product, where antibodies in the donor blood activate recipient neutrophils. The result is an inflammatory response in the vascular endothelium of the lung, producing acute lung injury.
- Two-hit model: Predisposing factors such as shock, tobacco use, chronic inflammation, or alcohol use serve as the first “hit.” The second “hit” comes from antibodies, lipid mediators, extracellular vesicles, or older blood cells in the transfused product. Together, these triggers set off the inflammatory reaction in the lungs.
TRALI risks
Critically ill patients receiving plasma-rich blood products are at high risk for TRALI. Furthermore, higher TRALI incidents were reported with plasma from donors who have a history of pregnancy.
TACO risks
Patients over 60 years old, female patients, patients with preexisting heart conditions, renal dysfunction or failure, or chronic pulmonary disease are at risk for TACO. Subsequently, risk increases with the volume of blood products infused, positive fluid balance, insufficient use of diuretics, and faster transfusion rates.
Diagnosis and symptoms: TACO vs TRALI
TRALI symptoms are respiratory embarrassment, hypoxemia, chest radiographic evidence within five to six hours of transfusion, and hypotension. When diagnosing between TRALI and TACO, remember that TRALI is noncardiogenic in nature and not categorized by blood pressure elevations. Furthermore, TRALI has an absence of a timely relationship to other lung injury-causing factors.
TACO symptoms are similar in nature. They include: an acute onset of respiratory distress, signs of congestive heart failure, hypertension, hypoxemia, and chest radiographic evidence. The CDC guidelines for diagnosing TACO include a diagnosis of pulmonary edema occurring within 6 hours of a blood transfusion that can’t be attributed to other known causes of an acute lung injury.
Management approaches for both TACO and TRALI
Identifying pre-transfusion risks and implementing prevention strategies for both TACO and TRALI is crucial for patient safety. However, the following interventions can be implemented once the patient is diagnosed with either TACO or TRALI.
TACO
Early suspicion and recognition are critical. Interventions include:
- Cessation of transfusion
- Elevation of the head of the bed
- Oxygen supplementation
- Diuretic therapy
- Asodilators
- Intubation and positive pressure ventilation as needed
- Consideration given to noninvasive ventilation
TRALI
While some interventions are similar to TACO, remember that TRALI will not respond to diuretic therapy.
- Oxygen supplementation
- Mechanical ventilation
- ICU and close monitoring
- Circulatory support
- Cessation of transduction
- Corticosteroids, if necessary.
Learn more about TACO vs. TRALI
Listen to APEX Anesthesia’s Audio Demo or read the PDF article for more detailed information.
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