Vagus nerve stimulation at the ear: Is it for breast cancer survivors?
What is Vagus n and stimulation?
Vagus nerves (two) are major players in receiving and sending information between the brain and the organs- heart, lungs, spleen, liver and all of the digestive organs. It is a large part of the nervous system (parasympathetic) that works to bring about calmness and restoration to the body.
Research into medical devices that stimulate the vagus nerves is very recent, yet the practices that directly impact on the vagus nerves are very ancient. The medical devices started with a nerve stimulation unit surgically implanted (internal) at the neck and more recently have progressed to external devices that use TENS ( transcutaneous electrical nerve stimulation device) connected to the ear. The ancient practices known to stimulate calming are meditation, chanting and singing (not sure about head banger music though) and the more recent diverse range of mindfullness practices.
There is amazing research that demonstrate the impact of Vagus nerve ear stimulation at the brain. The brain MRI studies have shown specific areas of the brain light up; reflecting activity & energy when the ear stimulation device is working. The location of stimulation at the ear has also been investigated using MRI: stimulation on the outer ear differs in the brain responses to that when stimulation is applied to the concha part of the ear. If you want to see an example then go to this full free access paper/research.
I loved viewing these MRI images, as it is rare for a clinician to see the inner body responding to our therapy. We tend to see the external results- patients report they feel less pain or can move their limbs better. The external results for TENS at the ear are that research subjects report positive changes in feelings of depression, anxiety, certain digestion issues and pain. These changes are have been significantly more than the placebo effect.
As a clinician I am particularly excited by both the low cost of the device and the ease for patients to learn to use TENS at the ear as a home- treatment program. The research treatment method has been really helpful in providing a cost effective service that can be replicated in the clinic. Most of the studies involved the subjects being asessed for TENS ear stimulation suitability and to establish electrical levels, with instruction and training in use of the device at home over a period of 4-8 weeks. This method adds to the cost effectiveness of TENS to the ear intervention.
Now the "buts" and more clarification.
An individual's symtoms do need to be assessed, so there can be a better understanding of what the body needs- calming or activation. There are also serious warnings that would make using the TENS unit at the ear a clear too high risk - such as if the person has a pacemaker or implantable cardioverter defibrillators (ICDs). Also there are a number of settings on every TENS machine and therfore individuals do need to have these settings and timing developed and monitored.
You can do a preliminary investigation into the capacity of your own Vagus N - more specifically the sensation at the skin, at the concha part of ear. Use a safe method to apply cool and then light touch to this area: both ears (not inside the ear canal!). Then compare the sense of feeling. If the nerve is a little low in transmission power - the sensation of light touch, cool and warm will be less. This testing method requires you to have one healthy vagus nerve to skin, to compare sensation between the ears.
It wont be for everyone-
B: " I just could not get both ear clips into the right place easily - my ear is very small and when I did- I felt quite nauseous afterwards. It just seemed too strong for my body"
In the joint review of the intervention with the patient, we decided the "dose" was too high- being too soon after major surgery. The patient decided to participate in meditation.
Ear stimulation for breast cancer survivors
Breast cancer survivors are more use to being directed to participate in mindfullness and meditation practices, for the health benefits. The research of these practices, which stimulate the parasympathetic system (the vagus nerves are most likely involved), is quite strong for the positive body + mind changes. Search the more than 150 research papers by Prof Linda Carlson and her team in Canada if you would like to read more details specifically linked touse with cancer survivors.
Stimulation at the ear had it's first small pilot investigation with breast cancer survivors by another method- auricular pressure point therapy- see Chao Hsing Yeh etal in 2016. This study used slightly different locations on the ear and used a manual stimulation method; Chinese seeds taped to the person's accupressure sites at the ear are manually massaged several times over the day. Two studies investigated changes to clusters of symptoms ( pain, fatigue, sleep disturbance) over 7 days and symptoms after 4 weeks. In both small group studies there were significant changes in syptom experiences. The first treatment group members had equal and greater than 30 % reduction in symptoms, while the later active treatment group reported a reduction of 71% in pain, 44% in fatigue, 31% in sleep disturbance, and 61% in interference with daily activities.
Manual ear stimulation of acupuncture points for breast cancer survivors was followed up in 2017 by Yeh etal. Pain and inflammation associated with joint pain, after certain breast cancer medication, was investigated. In this small pilot study, participants reported decreases in worst pain and pain interference, and improvements in physical function, cancer-related symptom severity, with notable changes in inflammation markers in blood analysis.
Although research is extremely limited for breast cancer specific use of TENS at the ear, there is sufficient evidence for safety for use and safety for home use, and more general recogntion of the importance of the links between the ear, the brain and and modulation of body inflammation.
I believe there is adequate research to support assessment and trial of ear stimulation for breast cancer survivors experiencing symptoms such as pain and inflammation. At present there are 2 methods- manual stimulation of acupressure points and TENS to the ear. I would especially love to see a pilot study in the use of Vagus N stimulation for fatigue associated with inflammation as commonly experienced by breast cancer survivors.
While waiting for further research- pilot studies and then larger study groups, I will introduce suitable patients to the potential of ear TENS stimulation and we will run single case trials and evaluate the outcomes together. A trial would require a health assessment, a short training session and then home program for 2-4 weeks followed up with a review. For the client- the cost of the device + ear plugs is near $100 - which can be loaned or purchase option can be considered. Assessment, training and review consult fees would make this intervention certainly worthy of consideration.
R: I go back and do a backup TENS at the ear home program when I notice that my head is a feeling cloudy/ foggy"
If you are interested in knowing more and there is no health professional trained in TENS ear stimulation in your town- this assessment and training service can be managed via video conferencing. Connect with Denise by email or check out fees and availability here at Becon HEALTH a secure payment, booking and online meeting website.