Venous Thromboembolism Prophylaxis in the Neurocritically Ill Population.

: Venous thromboembolism (VTE) is a preventable cause of morbidity in the neurocritical ill patient population. There is ongoing debate regarding the optimal timing and choice of pharmacologic thromboprophylaxis (PTP) and how these decisions relate to balancing the risk of bleeding complications with the development of VTE. Our review assesses the available data to provide un updated perspective to clinicians. : A literature search was performed in December 2024 in PubMed and EMBASE. We focused on the timing of PTP initiation and the comparison of enoxaparin (ENX) with unfractionated heparin (UFH) in patients with traumatic brain injury (TBI), intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), spinal or spinal cord injury (SCI), or requirement for neurosurgical intervention. : We included 90 articles spanning a total of 669,725 patients with injuries of interest within neurocritical care. The existing data largely signaled a benefit of early administration (<24-72 h) of PTP in VTE prevention, though some studies suggested increased risks of complications. Data to inform a preference for PTP agent was less robust, though a signal of benefit for enoxaparin is suggested for subsets of patients with acute brain injury such as TBI. The data quality is limited by the large body of retrospective studies, the heterogeneity of study populations, outcome definitions, study methodologies, and the lack of detailed reporting of relevant factors. : Our review provides an updated assessment of the available data on PTP timing and choice in neurocritically ill patients with hemorrhages or surgical need, with a practice-focused overview for clinicians balancing VTE risk with bleeding risk. The data suggest that in most circumstances, early PTP appears safe and indicated, and that low-molecular weight heparin (LMWH) can be considered over UFH in certain subsets of patients. Still, data gaps and conflicting results highlight the need for patient-specific decision making and indicate that more robust research is warranted to inform optimal clinical practice.