Platelets Transfusion
Aiya Almogaber, PharmD
New clinical guidelines from the Association for the Advancement of Blood & Biotherapies (AABB) recommend more restrictive use of platelet transfusions, reflecting a shift toward individualized thresholds and evidence-based decision making. The updated guidance published June 25, 2025, in JAMA redefines platelet transfusion practices for adults and children in both prophylactic and procedural settings.
The multidisciplinary guideline panel reviewed recent randomized clinical trials and systematic reviews to revise previous recommendations issued in 2015. The updated recommendations are intended to reduce unnecessary transfusions, support stewardship, and improve patient outcomes across a variety of clinical settings.
“Blood transfusion is the most commonly performed procedure in hospitals,” said Ryan Metcalf, MD, associate professor of pathology at the University of Utah and lead author on the guideline.
In the United States, roughly 2.2 million platelet transfusions are performed each year.
“They come with attendant risks and costs, so it made sense to update guidance to help clinicians make optimal decisions to maximize patient benefit and minimize risk,” Metcalf said.
The guideline has been endorsed by the American Society of Hematology, the American Society for Transplantation and Cellular Therapy, the International Society on Thrombosis and Haemostasis, and the Society for the Advancement of Blood Management.
Lower thresholds for prophylactic transfusion
“Most of our 11 recommendations were either new or significantly changed from prior AABB guidelines and ICTMG [International Collaboration for Transfusion Medicine Guidelines], representing a shift toward more restrictive transfusion strategies,” Metcalf said.
Among the most significant updates is the reaffirmation of a platelet count threshold of 10,000/µL for prophylactic transfusion in hospitalized adults with therapy-induced hypo-proliferative thrombocytopenia. This recommendation, supported by moderate-certainty evidence, reflects consistency across multiple trials showing reduced bleeding without a need for higher thresholds.
For pediatric patients with the same condition, the guideline now conditionally recommends the same 10,000/µL threshold, a change from the 2015 guidance that had left this decision to individual clinician judgment. Although data regarding children are less robust, the panel concluded that extrapolating adult evidence was reasonable, while also emphasizing close monitoring in younger patients.
The panel also does not recommend routine prophylactic transfusion for patients with chronic bone marrow failure syndromes such as myelodysplastic syndromes or aplastic anemia, citing low-certainty evidence and potential risks associated with repeated transfusions. Instead, transfusions should be guided by individual bleeding symptoms and procedural plans.
Procedural and surgical contexts
For those undergoing surgical or invasive procedures, platelet transfusion decisions should be based on a combination of patient factors, procedural bleeding risk, and clinical judgment. The guideline explicitly advises against prophylactic transfusion before minor procedures such as bone marrow aspiration or biopsy.
One notable change applies to patients undergoing cardiac surgery with cardiopulmonary bypass. In this group, the guideline authors recommend transfusion only in the setting of active bleeding and platelet dysfunction, rather than relying on specific laboratory thresholds alone. This shift acknowledges evidence that platelet count alone may not predict bleeding risk in these patients.
Special populations and platelet refractoriness
The guideline includes targeted recommendations for patients with hematologic malignancies, those undergoing hematopoietic stem cell transplantation, and patients with platelet refractoriness. For those who develop refractoriness, often due to alloimmunization, the panel conditionally recommends use of HLA-matched or cross-matched platelets, although they noted that evidence for improved clinical outcomes remains limited.
The guideline also highlights the need for further research in specific populations, including pediatric patients, those with chronic transfusion dependence, and patients receiving antiplatelet therapies. Several recommendations remain conditional, reflecting gaps in high-quality evidence and the need for clinician discretion in complex cases.
“While any patient receiving transfusion has some risk of harm from the intervention itself, the evidence didn’t clearly show that transfusing more platelets resulted in better outcomes,” said Metcalf. “Restrictive strategies appear to best balance benefit and risk based on current evidence.”
Metcalf said next steps include making the guidelines work in practice. ■