Vagus Nerve Flashcards
How does the Vagus Nerve link to Arrthythmia?
Where palpitations are not caused by a mechanical arrhythmia itself, then it is important to consider the role of the vagus nerve and autonomic nervous system.
The vagus nerve provides considerable innervation to many organs within the body,
one of which is the heart.
If there is vagus nerve dysfunction, potentially this can lower blood pressure while at the same time sending compensatory signals to the heart to increase rate to maintain blood pressure.
Lowered BP - leading to increasing heart rate - may lead to subjective palpitations
Where is the location and what is the role of the vagus nerve?
Vagus nerve anatomical location
* Otherwise known as cranial nerve 10 (X)
* Primarily targets autonomic neurons in the thoracic and upper abdominal cavities.
This nerve has multiple roles.
The vagus nerve exerts effects on multiple organ systems including the heart, digestion
and breathing. It provides an important link between the brain and these systems. How does it do this?
- Cervical part of the vagus nerve in your neck, gives off several branches - sensory (detecting) and parasympathetic (resting) innervation to the heart, lungs, and oesophagus
- Further down, recurrent laryngeal nerve branches off to the aortic arch to innervate the laryngeal muscles - throat and breathing
- Auricular branch carries sensory information from the hearing apparatus inside the ear
- Passes through the diaphragm alongside the oesophagus and gives off several branches - sensory and parasympathetic innervation to the gastrointestinal tract, the pancreas, the liver, and the adrenal glands
The vagus nerve has a regulating effect on all these systems.
How might we use the Vagus nerve in emergency medicine or self help?
While we are not primarily concerned with how to treat acute arrhythmias, it offers useful insight into patients potential experiences to understand how heart arrhythmias may be treated in an A&E setting.
Vagus nerve stimulation has been shown by some research to have a regulating and steadying effect on the cardiovascular system. Methods of stimulation in A&E may include:
* Valsalva manoeuvre entailing performing forceful exhalation – taking deep breaths and blowing into a syringe
* Vagus nerve neck massage
Vagus nerve self help - As well as herbal treatment for disordered vagus nerve function, offering our patients techniques and activities to help their autonomic function is very valuable. These can include:
* Slow deep breathing to activate the parasympathetic nervous system –
providing education on correct technique to avoid hyperventilation is important
* Yoga – slower more contemplative practices such as hatha yoga are more relevant here
* Meditation – there are huge varieties of meditative techniques available in order that patients can find what suits them. Walking meditation, especially in natural environments, can be very helpful for more restless patients
* Beneficial stimulation of the vagus nerve can be achieved with cold water on the face – cold water swimming may be an enjoyable way for patients to access this and engage in exercise to provide overall cardiovascular benefits.
