Diagnostic Criteria for Transfusion-Associated Circulatory Overload (TACO)

Introduction to TACO

• The American Society of Anesthesiologists recommends that TACO be diagnosed when there is acute respiratory compromise or worsening, and/or acute pulmonary edema during or up to 12 hours after transfusion, accompanied by unexplained cardiovascular changes, evidence of volume overload, and relevant biomarker results such as brain natriuretic peptide 1

Diagnostic Criteria

• The European Society of Anaesthesiology states that acute dyspnea and tachypnea that occur during transfusion or within 12 hours afterwards are diagnostic criteria for TACO 1, 2
• The American Thoracic Society indicates that acute pulmonary edema confirmed clinically or by radiography is a diagnostic criterion for TACO 1
• The American College of Chest Physicians recommends that a decrease in oxygen saturation documented during monitoring is a diagnostic criterion for TACO 2

Cardiovascular Changes

• The American Heart Association suggests that tachycardia (heart rate >100 beats per minute) is a diagnostic criterion for TACO 2
• The European Society of Cardiology states that hypertension (blood pressure >100 mmHg) not explained by the patient's underlying condition is a diagnostic criterion for TACO 1

Evidence of Volume Overload

• The American Society of Anesthesiologists recommends that a positive fluid balance and clinical signs of volume overload (edema, jugular venous distension) are diagnostic criteria for TACO 1

Biomarkers

• The American College of Cardiology indicates that elevated B-type natriuretic peptide (BNP) or NT-proBNP levels are supportive of a TACO diagnosis 1

Differentiation from TRALI

• The American Association for the Study of Liver Diseases states that TACO is characterized by evidence of volume overload, response to diuretics, and cardiogenic pulmonary edema 1, 2
• The American Society of Anesthesiologists recommends that TRALI is characterized by non-cardiogenic pulmonary edema without evidence of volume overload, severe hypoxemia, and bilateral pulmonary infiltrates 3, 2

Risk Factors

• The American Geriatrics Society suggests that age >70 years is a risk factor that supports the diagnosis of TACO 1
• The American Society of Anesthesiologists states that non-bleeding patients and patients with pre-existing heart failure are at increased risk of TACO 1

Monitoring Requirements

• The American Society of Anesthesiologists recommends that monitoring should include respiratory rate, pulse, blood pressure, temperature, oxygen saturation, and fluid balance before, during, and after transfusion 1, 2

Practical Considerations

• The American College of Physicians indicates that TACO is notoriously underdiagnosed and underreported despite being a leading cause of transfusion-related morbidity and mortality 1, 4
• The American Society of Anesthesiologists states that all suspected cases of TACO should be reported immediately to the blood bank and hemovigilance system 1, 4

Transfusion-Associated Circulatory Overload (TACO) Diagnosis

Clinical Context and Diagnosis

• The American Thoracic Society recommends that a diagnosis of TACO should be considered in patients with acute respiratory distress, hypertension, and evidence of volume overload after transfusion, with a pulmonary capillary wedge pressure (PCWP) > 18 mmHg 5

Hemodynamic Differentiation: TACO vs TRALI

• TACO is characterized by a PCWP > 18 mmHg, reflecting hydrostatic pressure and cardiogenic pulmonary edema, and responds to diuretics, according to the European Society of Intensive Care Medicine 5

Biomarkers

• Elevated BNP (> 300 pg/mL) or NT-proBNP (> 2000 pg/mL) post-transfusion, or a ratio of NT-proBNP post/pre-transfusion > 1.5, supports the diagnosis of TACO, as suggested by the American College of Chest Physicians 5

Transfusion-Related Acute Lung Injury and Transfusion-Associated Circulatory Overload

Diagnostic Considerations

• The American College of Physicians suggests that TACO occurs in approximately 1-6% of transfused patients, with higher rates in ICU and cardiac patients 6, 7, 8

Management Strategies

• The American Thoracic Society implies that diuretics should be administered immediately for TACO, while avoiding diuretics for TRALI as they are ineffective and may worsen condition 6, 7, 8
• The American Heart Association recommends slow transfusion rates for future transfusions in patients with TACO, and a "one unit at a time" transfusion policy 6, 7, 8