Vagus nerve stimulation to augment recovery from severe traumatic brain injury impeding consciousness: a prospective pilot clinical trial.

Source

New York University School of Medicine and NYU Langone Medical Center, New York, NY, USA.

Abstract

OBJECTIVES:

Traumatic brain injury (TBI) has high morbidity and mortality in both civilian and military populations. Blast and other mechanisms of TBI damage the brain by causing neurons to disconnect and atrophy. Such traumatic axonal injury can lead to persistent vegetative and minimally conscious states (VS and MCS), for which limited treatment options exist, including physical, occupational, speech, and cognitive therapies. More than 60 000 patients have received vagus nerve stimulation (VNS) for epilepsy and depression. In addition to decreased seizure frequency and severity, patients report enhanced mood, reduced daytime sleepiness independent of seizure control, increased slow wave sleep, and improved cognition, memory, and quality of life. Early stimulation of the vagus nerve accelerates the rate and extent of behavioral and cognitive recovery after fluid percussion brain injury in rats.

METHODS:

We recently obtained Food and Drug Administration (FDA) approval for a pilot prospective randomized crossover trial to demonstrate objective improvement in clinical outcome by placement of a vagus nerve stimulator in patients who are recovering from severe TBI. Our hypothesis is that stimulation of the vagus nerve results in increased cerebral blood flow and metabolism in the forebrain, thalamus, and reticular formation, which promotes arousal and improved consciousness, thereby improving outcome after TBI resulting in MCS or VS.

DISCUSSION:

If this study demonstrates that VNS can safely and positively impact outcome, then a larger randomized prospective crossover trial will be proposed.

PMID:: 23485054; [PubMed - in process]

http://www.ncbi.nlm.nih.gov/pubmed/23485649

Tuesday, March 13, 2012

Is there a role for vagus nerve stimulation therapy as a treatment of traumatic brain injury?

Br J Neurosurg. 2012 Mar 10. [Epub ahead of print]

Is there a role for vagus nerve stimulation therapy as a treatment of traumatic brain injury?

Kumaria A, Tolias CM.

Source

Department of Neurosurgery, Wessex Neurological Centre , Southampton.

Abstract

This paper aims to review the current literature on vagus nerve stimulation (VNS) use in animal models of traumatic brain injury (TBI) and explore its potential role in treatment of human TBI. A MEDLINE search yielded four primary papers from the same group that demonstrated VNS mediated improvement following fluid percussion models of TBI in rats, seen as motor and cognitive improvements, reduction of cortical oedema and neuroprotective effects. The underlying mechanisms are elusive and authors attribute these to attenuation of post traumatic seizures, a noradrenergic mechanism and as yet undetermined mechanisms. Reviewing and elaborating on these ideas, we speculate other potential mechanisms including attenuation of peri-infarct depolarisations, attenuation of glutamate mediated excitotoxicity, stabilisation of intracranial pressure, enhancement of synaptic plasticity, upregulation of endogenous neurogenesis and anti-inflammatory effects may have a role. Although this data unequivocally shows that VNS improves outcome from TBI in animal models, it remains to be determined if these findings translate clinically. Further studies are warranted.

PMID:: 22404761; [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/22404761