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The online version of this article (doi:10.1186/1752-2897-8-15) contains supplementary material, which is available to authorized users.
The authors declare that they have no competing interests.
JBRN, conceived the study, participated in the design and coordination, drafted the manuscript and performed statistical analysis. RLA, participated in the design and manuscript drafting, performed the assays and surgical procedures. MC Jr., Participated in the design of the study and performed the assays and surgical procedures. TA, Participated in the design of the study, performed the assays and surgical procedures. CT, Performed the assays and surgical procedures, participated in the manuscript drafting. CK, participated in the design of the study and surgical procedures. MA, Performed the assays, statistical analysis and manuscript drafting. SBR, participated in the design, coordination, and manuscript drafting. JRCM participated in the design, coordination, and performed the assays. All authors read and approved the final manuscript.
Inflammation plays a major role in the multifactorial process of trauma associated coagulopathy. The vagus nerve regulates the cholinergic anti-inflammatory pathway. We hypothesized that efferent vagus nerve stimulation (VNS) can improve coagulopathy by modulating the inflammatory response to hemorrhage.
Wistar rats (n = 24) were divided in 3 groups: Group (G1) Sham hemorrhagic shock (HS); (G2) HS w/o VNS; (G3) HS followed by division of the vagus nerves and VNS of the distal stumps. Hemorrhage (45% of baseline MAPx15 minutes) was followed by normotensive resuscitation with LR. Vagus nerves were stimulated (3.5 mA, 5 Hz) for 30 sec 7 times. Samples were obtained at baseline and at 60 minutes for thromboelastometry (Rotem®) and cytokine assays (IL-1 and IL-10). ANOVA was used for statistical analysis; significance was set at p < 0.05.
Maximum clot firmness (MCF) significantly decreased in G2 after HS (71.5 ± 1.5 vs. 64 ± 1.6) (p < 0.05). MCF significantly increased in G3 compared to baseline (67.3 ± 2.7 vs. 71.5 ± 1.2) (p < 0.05). G3 also showed significant improvement in Alfa angle, and Clot Formation Time (CFT) compared to baseline. IL-1 increased significantly in group 2 and decrease in group 3, while IL-10 increased in group 3 (p < 0.05).
Electrical stimulation of efferent vagus nerves, during resuscitation (G3), decreases inflammatory response to hemorrhage and improves coagulation.