Here is an Allopathic aproach to Vagus Nerve inhibition and its effect on Post Traumatic Stress Disorder (PTSD):
The demonstrated technique can be easily integrated into a clinical trial of the efficacy of directly working with the Vagus Nerve in relation to PTSD issues, and it is exciting to think that they will be getting significant results from their study. The downside of using this approach is that the Vagus Nerve does a lot more than regulate Fight / Flight responses and blocking the nerve is something of a shotgun approach to recalibrating Autonomic Nervous System (ANS) response to stimulus. Symptoms may re-emerge as digestion, circulation, organ or allergic issues or in many other ways, and/or stress responses may return once the anesthetic effects wear off. There are other important aspects to recovery from trauma that this treatment sidesteps, such as working towards an acceptance and letting go of the traumatic experience.
The Manual Therapy approach to PTSD also works with the ANS, but not by partially inhibiting this primary system for self regulation. Re-balancing the subsystems of the ANS over some period of time allows for re-grouping or re-calibrating to the current stimulus environment, thereby raising the threshold for triggering stress responses.
Here is a link to a paper produced from a study at University of Texas in which Vagus Nerve inhibition was used in conjunction with stimulus to recalibrate audio sensitivity in Tinnitus research: