What is the role of platelets in spontaneous Subdural Hemorrhage (SDH)?

From the Guidelines

Platelet transfusion is not recommended as a routine treatment for spontaneous Subdural Hemorrhage (SDH) unless there is evidence of thrombocytopenia or platelet dysfunction, as stated in the AABB clinical practice guideline from 2015 1. In patients with spontaneous SDH, the role of platelets is crucial in primary hemostasis, but the decision to transfuse platelets should be individualized based on various clinical factors, including the size of the bleeding and the patient's level of consciousness.

• The AABB guideline recommends against routine platelet transfusion for nonbleeding cardiac surgical patients, and this principle can be applied to spontaneous SDH patients with normal platelet counts and function.
• For patients on antiplatelet medications who develop spontaneous SDH, platelet transfusion may be considered, particularly if urgent neurosurgical intervention is needed, as suggested by the guideline 1.
• The typical transfusion dose is 1 unit of apheresis platelets or 4-6 units of random donor platelets, but this should be tailored to the individual patient's needs.
• Management should focus on addressing the underlying cause of the spontaneous SDH, reversing any coagulopathy, and neurosurgical consultation for possible evacuation if the hematoma is large or causing significant mass effect. The rationale behind selective platelet transfusion is that platelets are essential for primary hemostasis, but unnecessary transfusions expose patients to risks including transfusion reactions, infection transmission, and alloimmunization without providing clinical benefit, as highlighted in the guideline 1.

From the Research

Role of Platelets in Spontaneous Subdural Hemorrhage (SDH)

• Platelets play a crucial role in the development and management of spontaneous SDH, as evidenced by studies on patients taking antiplatelet medication 2, 3.
• The use of antiplatelet therapy is common and can complicate the operative management of SDH, with patients on antiplatelet medication being more likely to receive preoperative platelet transfusion 2.
• However, preoperative platelet transfusion did not reduce reoperation rates in patients on antiplatelet medication 2.
• Spontaneous SDH can occur in patients receiving dual antiplatelet therapy, and rapid discontinuation of antiplatelet drugs and hematoma evacuation are necessary for management 3.
• Underlying medical conditions such as thrombocytopenia, immunosuppression, and hypertension can contribute to the development of spontaneous SDH, with abnormal platelet count being a common finding 4.

Platelet Transfusion and Management

• Platelet transfusion may be effective for performing emergency surgery for intracranial hemorrhage, even in patients with heparin-induced thrombocytopenia (HIT) 5.
• Correcting platelet deficiencies is a potential preventive measure for spontaneous SDH 4.
• Management of hemorrhagic patients under antithrombotic therapy is challenging, and resuming or stopping treatment can lead to recurrence bleeding or thrombotic risk 3.

Complications and Associations

• Spontaneous SDH can be severe and is often associated with subarachnoid hemorrhage and/or intraparenchymal hemorrhage 4.
• The use of circulatory devices or hemodialysis is noted in a significant portion of spontaneous SDH cases 4.
• Heparin-induced thrombocytopenia can lead to acute subdural hematoma, which is a rare but serious complication 5.