Unfractionated heparin after TBI reduces in vivo cerebrovascular inflammation, brain edema and accelerates cognitive recovery.

Authors

• Katsuhiro Nagata
• Kenichiro Kumasaka
• Kevin D Browne
• Shengjie Li
• Jesse St-Pierre
• John Cognetti
• Joshua Marks
• Victoria E Johnson
• Douglas H Smith
• Jose L Pascual

Publication/Presentation Date

12-1-2016

Abstract

BACKGROUND: Severe traumatic brain injury (TBI) may increase the risk of venous thromboembolic complications; however, early prevention with heparinoids is often withheld for its anticoagulant effect. New evidence suggests low molecular weight heparin reduces cerebral edema and improves neurological recovery after stroke and TBI, through blunting of cerebral leukocyte (LEU) recruitment. It remains unknown if unfractionated heparin (UFH) similarly affects brain inflammation and neurological recovery post-TBI. We hypothesized that UFH after TBI reduces cerebral edema by reducing LEU-mediated inflammation and improves neurological recovery.

METHODS: CD1 male mice underwent either TBI by controlled cortical impact (CCI) or sham craniotomy. UFH (75 U/kg or 225 U/kg) or vehicle (VEH, 0.9% saline) was administered 2, 11, 20, 27, and 34 hours after TBI. At 48 hours, pial intravital microscopy through a craniotomy was used to visualize live brain LEUs interacting with endothelium and microvascular fluorescein isothiocyanate-albumin leakage. Neurologic function (Garcia Neurological Test, GNT) and body weight loss ratios were evaluated 24 and 48 hours after TBI. Cerebral and lung wet-to-dry ratios were evaluated post mortem. ANOVA with Bonferroni correction was used to determine significance (p < 0.05).

RESULTS: Compared to positive controls (CCI), both UFH doses reduced post-TBI in vivo LEU rolling on endothelium, concurrent cerebrovascular albumin leakage, and ipsilateral cerebral water content after TBI. Additionally, only low dose UFH (75 U/kg) improved GNT at both 24 and 48 hours after TBI. High dose UFH (225 U/kg) significantly increased body weight loss above sham at 48 hours. Differences in lung water content and blood pressure between groups were not significant.

CONCLUSIONS: UFH after TBI reduces LEU recruitment, microvascular permeability, and brain edema to injured brain. Lower UFH doses concurrently improve neurological recovery whereas higher UFH may worsen functional recovery. Further study is needed to determine if this is caused by increased bleeding from injured brain with higher UFH doses.

Volume

81

Issue

6

First Page

1088

Last Page

1094

ISSN

2163-0763

Published In/Presented At

Nagata, K., Kumasaka, K., Browne, K. D., Li, S., St-Pierre, J., Cognetti, J., Marks, J., Johnson, V. E., Smith, D. H., & Pascual, J. L. (2016). Unfractionated heparin after TBI reduces in vivo cerebrovascular inflammation, brain edema and accelerates cognitive recovery. The journal of trauma and acute care surgery, 81(6), 1088–1094. https://doi.org/10.1097/TA.0000000000001215

Disciplines

Business Administration, Management, and Operations | Health and Medical Administration | Management Sciences and Quantitative Methods

PubMedID

27533909

Department(s)

Administration and Leadership

Document Type

Article