From the Guidelines
Prophylactic anticoagulation in patients with intracranial bleeding can be started as early as 24-48 hours after the bleeding has stabilized, as evidenced by a stable CT scan, with the goal of minimizing the risk of venous thromboembolism while avoiding the risk of promoting ICH expansion. According to the 2022 guideline for the management of patients with spontaneous intracerebral hemorrhage from the American Heart Association/American Stroke Association 1, the timing of the first dose of UFH or LMWH prophylaxis after ICH is crucial. The guideline suggests that it may be reasonable to first document hemorrhage stability on CT if LMWH prophylaxis is started in the 24- to 48-hour window after ICH onset.
Some key points to consider when deciding on the timing of prophylactic anticoagulation include:
- The incidence of rebleeding or hematoma expansion was not higher in the early start versus the delayed start group in any of the studies 1
- The earliest start for any patient in these studies was 25 hours after admission, with a median of 42 hours after admission in one of the larger retrospective studies 1
- Hematoma size, but not timing of prophylaxis, was independently associated with hematoma expansion in a multivariable analysis 1
- In a large observational study, intracranial hemorrhagic complications were observed in 1.7% of patients who started prophylaxis (UFH or LMWH) 0 to 1 days after CT demonstrating stability 1
In terms of specific anticoagulation regimens, low-dose unfractionated heparin (5,000 units subcutaneously every 8-12 hours) or low molecular weight heparin (enoxaparin 40 mg subcutaneously daily) can be considered, with the choice of agent and dosing interval depending on the patient's individual risk factors and clinical status. Mechanical prophylaxis with intermittent pneumatic compression devices should be used in all patients from admission until ambulatory or until pharmacological prophylaxis is initiated. Regular neurological assessments and follow-up imaging are essential during the initial anticoagulation period to monitor for any signs of rebleeding.
From the Research
Timing of Prophylactic Anticoagulation in Patients with Intracranial Bleed
- The optimal time to start prophylactic anticoagulation in patients with intracranial bleed is not well established, and the decision should be made on a case-by-case basis, considering the risk of thromboembolism versus the risk of hemorrhage progression 2, 3, 4, 5, 6.
- A study published in 2013 suggested that anticoagulation can be safely withheld for a short period, up to 7-14 days, in patients with intracranial bleed and a prosthetic valve, with a low probability of thromboembolic events 3.
- Another study published in 2019 found that starting chemical DVT prophylaxis within 24 hours post-procedure in patients with intracranial hemorrhage was not associated with an increased risk of re-bleed or new hemorrhage, and was actually associated with an improvement in Glasgow Coma Scale (GCS) scores 4.
- A retrospective review of patients with traumatic intracranial hemorrhage who received anticoagulant therapy found that the median time from injury to starting anticoagulation was 8 days, and that immediate complications were rare, but delayed complications, including progression of acute to chronic subdural hematoma, did occur 5.
- A study published in 2011 found that early use of chemical thromboprophylaxis in patients with traumatic brain injury reduced the incidence of venous thromboembolism without increasing the risk of intracranial hemorrhage progression, and that patients who started prophylaxis within 48-72 hours had a lower incidence of VTE and a trend towards a lower rate of injury progression 6.
Key Considerations
- The risk of thromboembolism versus the risk of hemorrhage progression should be carefully weighed when deciding when to start prophylactic anticoagulation in patients with intracranial bleed 2, 3, 4, 5, 6.
- The type of intracranial hemorrhage, the presence of a prosthetic valve, and the patient's overall clinical condition should be taken into account when making this decision 3, 4, 5.
- Close monitoring for signs of hemorrhage progression or thromboembolic events is essential when starting prophylactic anticoagulation in patients with intracranial bleed 4, 5, 6.