AABB Develops New Platelet Transfusion Guidelines

A landmark set of new platelet transfusion guidelines, developed by AABB in partnership with the International Collaboration for Transfusion Medicine Guidelines (ICTMG), was published in JAMA today.

The new guidelines offer recommendations for transfusion based on specific patient criteria, and guidelines vary depending on patients’ needs. In general, the guidelines support the implementation of restrictive platelet transfusion strategies.

The authors of the new guidelines, led by Ryan Metcalf, MD, from the Department of Pathology at the University of Utah, noted that restrictive strategies reduce the risk of adverse reactions, mitigate platelet shortages and reduce costs. “It is good practice to consider overall clinical context and alternative therapies in the decision to perform platelet transfusion,” they wrote.

The guidelines were based on data from 21 randomized controlled trials and 13 observational studies, all of which examined transfusion strategies using restrictive or liberal amounts of platelets. The authors noted that overall evidence demonstrated that restrictive transfusion strategies were not associated with increased risk of mortality, or increased bleeding, in most patient populations.

Recommendations

The authors categorized their recommendations based on the degree of evidence. They developed the following recommendations considered to be “strong recommendations with high/moderate-certainty evidence”:

• To address hyperproliferative thrombocytopenia in nonbleeding patients receiving chemotherapy or undergoing allogeneic stem cell transplant, platelet transfusion is recommended when platelet count is less than 10x10³/µL.
• For consumptive thrombocytopenia in neonates without major bleeding, platelet transfusion is recommended when platelet count is less than 25x10³/µL.
• In patients undergoing lumbar puncture, platelet transfusion is recommended when platelet count is less than 20x10³/µL.
• In patients with consumptive thrombocytopenia due to dengue without major bleeding, platelet transfusion is not recommended.
  

The authors also developed guidelines for additional patient populations but noted that these are “conditional recommendations with low/very low-certainty evidence.”

These recommendations include:

• For hypoproliferative thrombocytopenia in nonbleeding adults undergoing autologous stem cell transplant or with aplastic anemia, prophylactical platelet transfusion is not recommended.
• In adults with consumptive thrombocytopenia without major bleeding, platelet transfusion is recommended when platelet count is less than 10 x10³/µL.
• In adults undergoing central venous catheter placement in compressible anatomic sites, platelet transfusion is recommended when platelet count is less than 10 x10³/µL.
• In adults undergoing interventional radiology, platelet transfusion is recommended when platelet count is less than 20 x10³/µL for low-risk procedures and less than 50 x10³/µL for high-risk procedures.
• For adults undergoing major nonneuraxial surgery, platelet transfusion is recommended when platelet count is less than 50 x10³/µL.
• For nonthrombocytopenic patients undergoing cardiovascular surgery in the absence of major hemorrhage, including those receiving cardiopulmonary bypass, platelet transfusion is not recommended.
• For nonoperative intracranial hemorrhage in adults with platelet count more than 100 x10³/µL, including those receiving antiplatelet agents, platelet transfusion is not recommended.
  

Claudia Cohn, MD, PhD, AABB’s chief medical officer and one of the authors of the guidelines, said these new guidelines were an important advancement for optimal transfusion strategies.

“These new evidence-based guidelines move the field forward for many different patient populations,” Cohn said. “Overall, the guidelines prioritize patient safety and help conserve the limited platelet inventory.”

In a related commentary published today in Transfusion, the authors underscored two major findings that informed the development of the new guidelines. First, they found that there is no consistent evidence that liberal platelet transfusion strategies improve mortality or reduce bleeding; and second, while current data support restrictive practices, the review found that evidence quality varies substantially across patient populations.

The commentary also highlighted existing gaps in the evidence base. In several clinical settings, including cardiopulmonary bypass, extracorporeal membrane oxygenation and interventional radiology, robust data from randomized controlled trials are still lacking.

According to the authors, these knowledge gaps point to the need for continued research to refine transfusion practices and better align them with patient-specific risk profiles. As platelet demand continues to challenge transfusion services globally, they believe the review and resulting guidelines offer a foundation for both clinical decision-making and targeted future studies.

“Transfusion services are facing challenges meeting platelet demands,” the authors concluded, “and our review provides an evidence synthesis to inform quality improvement initiatives and development of mitigation strategies/shortage plans."