Comparison of safety and efficacy of lower-intensity versus standard unfractionated heparin infusion nomograms for extracranial venous thromboembolism in the neurological intensive care unit.
Hakoun A, Gupta M, et al. • Clinical neurology and neurosurgery • 2026
Lower-intensity UFH targeting aPTT 40-65s was associated with significantly less major bleeding than standard-intensity UFH targeting aPTT 60-100s, while both regimens were associated with lower odds of VTE progression compared to no therapeutic anticoagulation in neurological ICU patients.
Key Findings
Results
Major bleeding occurred significantly more often with standard-intensity UFH than lower-intensity UFH in neurological ICU patients with acute extracranial VTE.
Major bleeding rate was 18.5% with standard-intensity UFH versus 4.0% with lower-intensity UFH (p = 0.02)
In multivariate analysis, standard-intensity UFH was associated with higher odds of major bleeding compared with lower-intensity UFH (adjusted OR 4.63; 95% CI 1.18-18.10; p = 0.03)
Results
Both lower-intensity and standard-intensity UFH were each independently associated with lower odds of VTE progression compared to no therapeutic anticoagulation.
Lower-intensity UFH was associated with lower odds of VTE progression vs. no anticoagulation (adjusted OR 0.32; 95% CI 0.12-0.87; p = 0.03)
Standard-intensity UFH was also associated with lower odds of VTE progression vs. no anticoagulation (adjusted OR 0.15; 95% CI 0.05-0.43; p < 0.01)
Treatment failure was defined as clinical or radiographic VTE progression
105 patients received no therapeutic anticoagulation, serving as the comparator group
Methods
The study cohort consisted of 236 neurological ICU patients with acute extracranial VTE meeting inclusion criteria out of 443 initially identified.
443 patients were diagnosed with acute VTE between June 2018 and April 2024 at a single center
236 patients met inclusion criteria: 81 received standard-intensity UFH, 50 received lower-intensity UFH, and 105 received no therapeutic anticoagulation
VTE included deep venous thrombosis and/or pulmonary embolism
This was a retrospective single-center study design
Background
Patients in the neurological ICU with acute brain injury or recent neurosurgery represent a high-risk population for hemorrhagic complications during anticoagulation for VTE.
The study was specifically conducted in the neurological intensive care unit setting
The authors note that anticoagulation for acute VTE in this population 'is challenging because patients with acute brain injury or recent neurosurgery are at high risk for hemorrhagic complications'
Lower-intensity UFH nomograms were described as having 'poorly defined' safety and effectiveness prior to this study
The authors note that 'unfractionated heparin infusions are commonly used, sometimes with lower activated partial thromboplastin time targets'
Conclusions
Lower-intensity UFH may offer a safer therapeutic balance for selected brain-injured patients with extracranial VTE, though the authors note prospective validation is needed.
The authors concluded that lower-intensity UFH 'may offer a safer therapeutic balance for selected brain-injured patients with extracranial VTE'
The study was retrospective and single-center, limiting generalizability
Multivariate analysis was used to adjust for confounders when comparing bleeding and VTE progression outcomes
The authors explicitly called for 'prospective validation' of these findings
What This Means
This research examined how to safely treat blood clots (venous thromboembolism, or VTE) in patients admitted to a neurological intensive care unit — a group that includes people recovering from strokes, brain injuries, or brain surgery. These patients are at particularly high risk of dangerous bleeding if given blood thinners, so finding the right dosing strategy is critical. The study compared three approaches: a standard-dose heparin drip, a lower-dose heparin drip, and no blood-thinning treatment at all, looking at outcomes in 236 patients treated over about six years at a single hospital.
The study found that patients who received the standard-dose heparin had major bleeding events more than four times as often as those who received the lower-dose heparin (18.5% vs. 4.0%). Despite using a lower dose, patients on the lower-intensity heparin still had significantly fewer cases of their blood clots getting worse compared to patients who received no anticoagulation at all. In other words, the lower-dose approach appeared to reduce clot progression while causing substantially less serious bleeding than the standard approach.
This research suggests that for neurological ICU patients who develop blood clots, using a lower-intensity heparin regimen — one that keeps blood-thinning levels slightly lower than the typical standard — may provide meaningful clot protection while reducing the risk of dangerous bleeding complications. However, because this was a single-center retrospective study (meaning it looked back at past patient records rather than prospectively testing an intervention), the authors caution that larger, prospective studies are needed to confirm these findings before they can be broadly adopted as standard practice.
Hakoun A, Gupta M, Dhar R, Mardani M, Koc F, Keyrouz S. (2026). Comparison of safety and efficacy of lower-intensity versus standard unfractionated heparin infusion nomograms for extracranial venous thromboembolism in the neurological intensive care unit.. Clinical neurology and neurosurgery. https://doi.org/10.1016/j.clineuro.2026.109512