Platelets are commonly transfused either therapeutically or prophylactically to maintain hemostasis. Most platelet transfusions are used to manage patients with hematologic malignancies. Although platelet transfusion guidelines have been published, platelet transfusion practices are still heterogeneous. Platelet transfusion guidelines partly lack recommendations or differ in the platelet threshold recommendations in some clinical situations. This article reviews platelet transfusions focusing on transfusion guidelines and platelet thresholds in different clinical settings.
Although platelet transfusion thresholds have not changed, the demand for platelets has increased, with most of the transfusions used in managing patients with hematologic malignancies.
Platelet products are prepared either by concentrating the platelets from whole-blood donations (known as platelet concentrates [PCs]), or by collecting platelets directly from donors via automated apheresis procedures (known as apheresis platelets [APs] or single-donor platelets). APs are more widely used in the United States and have certain advantages and drawbacks compared with PCs.
Platelet transfusion guidelines have been published; however, they are not consistently being followed, lack recommendations on some clinical scenarios, or differ in the platelet threshold recommendations in some clinical settings.
Platelet transfusion guidelines from different medical societies concur with strongly recommending prophylactic platelet transfusion in the setting of severe hypoproliferative thrombocytopenia (≤10,000/μL) following chemotherapy or allogeneic bone marrow transplant.
Platelet transfusion decisions, whether for prophylactic or therapeutic indications, should be weighed against the risks of transfusion side effects, refractoriness, contraindications in some clinical settings, and platelet product availability.
Platelets are commonly transfused blood components in many clinical settings, either therapeutically to manage acute hemorrhage or prophylactically to prevent bleeding when the platelet count decreases to less than a certain threshold or before a procedure. Platelets maintain hemostasis by controlling hemorrhage after blood vessel endothelial disruption. This process involves platelet adhesion, activation, and aggregation to form a platelet plug at the site of injury, thus maintaining vascular integrity.
According to the American Red Cross, approximately 7000 units of platelets are transfused daily in the United States. The demand for platelets has increased in spite of the unchanging prophylactic platelet transfusion thresholds. Some factors that could have contributed to the increase in platelet demand are a growth in the general population, an increase in the incidence of hematologic malignancies in an aging population, and changing practices in managing hematologic malignancies. It is estimated that two-thirds of platelet components are used in managing patients with hematologic malignancies.
Some platelet transfusion guidelines have been developed ; however, platelet transfusion practices are still heterogeneous because the available transfusion guidelines are not consistently followed and their implementation may be challenging in some practices. In addition, these guidelines either lack recommendations or differ in the platelet threshold recommendations in some clinical settings, such as surgery and invasive procedures. When deciding on platelet transfusions, physicians are encouraged to consider the possible adverse events of transfusion, and the costs and labor associated with platelet acquisition. It is worth noting that platelet triaging processes followed by blood banks to maintain an adequate inventory can sometimes affect the decision to transfuse platelets. This article presents an update on platelet transfusion, focusing on transfusion guidelines and platelet thresholds in different clinical settings.