Five possible causes of passing out with similar conditions to playing and releasing extended high notes on a trumpet.
Material taken from Wikapedia.com
1. Syncope (faint) is a sudden fall of blood pressure resulting in loss of consciousness.
2. Valsalva maneuver or Valsalva manoeuvre. The Valsalva maneuver is performed by attempting to exhale against a closed airway. This can be done by keeping the mouth closed and pinching the nose while trying to breath out. This maneuver greatly increases pressures inside the chest cavity – which stimulates the vagus nerve and increases vagal tone.
3. Orthostatic hypotension, also known as postural hypotension, and colloquially as head rush or dizzy spell, is a form of hypotension in which a person’s blood pressure suddenly falls when standing up or stretching.
4. Hyperventilation can sometimes cause symptoms such as numbness or tingling in the hands, feet and lips, lightheadedness, dizziness, headache, chest pain, flexor spasm of hands and feet, slurred speech, nervous laughter, and sometimes fainting, particularly when accompanied by the Valsalva maneuver.
Notice that I have mentioned FIVE possible causes and have listed only four so far. The fifth will be explained at the conclusion of this post.
The vagus nerve also called pneumogastric nerve or cranial nerve X, is the tenth of twelve (excluding CN0) paired cranial nerves. Upon leaving the medulla between the medullary pyramid and the inferior cerebellar peduncle, it extends through the jugular foramen, then passing into the carotid sheath between the internal carotid artery and the internal jugular vein down below the head, to the neck, chest and abdomen, where it contributes to the innervation of the viscera. Besides output to the various organs in the body, the vagus nerve conveys sensory information about the state of the body’s organs to the central nervous system. 80-90% of the nerve fibers in the vagus nerve are afferent (sensory) nerves communicating the state of the viscera to the brain.
The vagus is also called the pneumogastric nerve since it innervates both the lungs and the stomach.
The motor division of the vagus nerve is derived from the basal plate of the embryonic medulla oblongata, while the sensory division originates from the cranial neural crest.
The vagus nerve includes axons which emerge from or converge onto three nuclei of the medulla:
1. The Dorsal nucleus of vagus nerve – which sends parasympathetic output to the viscera, especially the intestines
2. The Nucleus ambiguus – which sends parasympathetic output to the heart (slowing it down) and
3. The Solitary nucleus – which receives afferent taste information and primary afferents from visceral organs
Also from Wikapedia.com-
The nucleus ambiguus in its “external formation” contains cholinergic preganglionic parasympathetic neurons for the heart. These neurons are cardioinhibitory.This cardioinhibitory effect is one of the means by which quick changes in blood pressure are achieved by the central nervous system (the primary means being changes in sympathetic nervous system activity, which constricts arterioles and makes the heart pump faster and harder). That is, through integrated and antagonistic system with sympathetic outflow from thevasomotor center of the brainstem, the parasympathetic outflow arising from the nucleus ambiguus and dorsal motor nucleus of the vagus nerve acts to decrease cardiac activity in response to fast increases in blood pressure. The external formation of the nucleus ambiguus also sends bronchoconstrictor fibers to the bronchopulmonary system, which can produce reflexive decreases in pulmonary bronchial airflow. The pathophysiologic relevance of this system, which may act in concert with the cardioinhibitory system, is poorly understood, but likely plays a role in bronchospastic diseases like COPD/emphysema (in which inhaled anticholinergic medications such as Spiriva/tiotropium oripratropium are standard-of-care treatment) and asthma, particularly for exercise-related asthma exacerbations, which may have a component of autonomic dysregulation.
Now that we have seen material which means very little to the average trumpet player, what does it all mean?
Causes not particular to our trumpet situation-
Hyperventilation may be the reason for passing out for anxious moments in a performance can and does bring on lesser symptoms of what we are studying. But the more savvier symptoms of our cases are more aggressive than mere anxiety and we need to look deeper into the cause.
Orthostatic hypotension, although similar to our situation, it does not take into consideration the element of restricted back pressure in the respiratory channel.
Causes similar to playing and releasing high notes-
Syncope certainly fits the form for our study for a sudden drop in blood pressure could be the cause of passing out.
The Valsalva maneuver is performed by attempting to exhale against a closed airway which is exactly what we are doing when sustaining and eventually releasing a high note.
Possable reason #5
All of this information explains how a drop in blood pressure can cause a blackout, but could there be another reason (reason #5) for the drop in blood pressure? Could there be something in the action taken by the player that triggers the loss in blood pressure?
During most of my teaching history, I taught my students that the real cause of a blackout was caused from the expansion of the throat against the blood vessels in that area. I also taught, and still do believe that the release of the note and the sudden decrease in the restrictions in the area of the throat allowed the blood to suddenly resume its travel into the brain which caused the player to become dizzy and possibly pass out.
An additional instruction was that as the feeling of dizziness starts to set in, the player should tuck his/her chin tightly into his/her chest and the affect of the blood pressure change could be substantially minimized.
Fortunately or unfortunately, I have not had the dizziness symptoms for many years and am unable to test this theory. When I was experiencing the dizziness, the “tuck the chin” exercise worked every time.
When trying this movement remember to tuck the chin in tight and stretch the back of the neck as much as possible.
Some might ask “What does this movement have to do with the blood flow. I believe that the “tucked in position” slightly restricts the sudden increase of blood to the brain enough to lessen the sudden impact of the blood rush.
Sounds very brutal doesn’t it?
Let me assure you that it is not as dangerous as it sounds. The only reason I have discussed the “Pass Out” subject is to give you a warning for the only real danger you might be faced with would be waking up to find you might have fallen and damaged your instrument.