Dyspnea on exertion is caused by various factors. However, low body oxygenation is the
key parameter and is always present in people with this symptom. Mouth breathing and chest breathing are
among the main additional causes of exertional dyspnea since they reduce body
and brain oxygenation and create the
sensation of air hunger (shortage of air) similar to that experienced by people with heart disease and cancer. However, those who have diabetes or COPD (e.g., asthma or bronchitis) and many other chronic conditions are also most likely to experience this debilitating symptom, as many studies indicate.
What do we know about their body oxygenation and
breathing at rest? Why do people with chronic diseases, but not healthy people,
experience exertional dyspnea? What are the main problems with oxygen transport
in the sick? Consider the following evidence.
hyperventilation (or having an automatic deep-breathing pattern) leads to alveolar hypocapnia (lack of CO2),
which causes low oxygen levels in body cells. Therefore, these people have
more problems during physical exertion since any forms of exercise require
additional oxygen, causing dyspnea
Healthy or normal breathing is very calm, minimal, and slow. It is imperceptible or unperceivable (only
about 500 ml for tidal volume, and 10-12 breaths/min with 6 L/min for minute ventilation at rest
for a 70-kg person). Patients with dyspnea commonly have over 12 L/min (double the norm) for
their ventilation rates at rest and over 18 breaths/min for respiratory
Overbreathing greatly increases the working demand of one's breathing due to large
minute ventilation rates and causes many other adverse effects, asides from exertional dyspnea.
Exacerbating causes in the pathophysiology of exertional dyspnea are:
-Oral breathing (due to reduction in NO or nitric oxide absorption and alveolar CO2)
-Thoracic breathing (due to reduction in the arterial oxygenation causing
-Presence of chronic inflammation and sputum in airways, causing further
narrowing or obstruction of air movement.
Physical exertion, due to anaerobic cell respiration at rest and
elevated resting blood lactate, worsens gas exchange and causes further overbreathing
and additional losses in alveolar CO2.
This then leads to acute exertional dyspnea. Acute dyspnea leads to even heavier and
faster breathing due to a negative feedback in breathing control caused by a
prominent O2 drive (hunger for air), instead of normal CO2-based control of respiration. Respiratory
receptors located in the brain sense low brain oxygenation, and create the
sensation of air hunger with a subsequent attempt to increase ventilation.
This YouTube video clip "Dyspnea"
explains causes and treatment of dyspnea in people with chronic diseases.
Significant reduction in exertional dyspnea has been found in numerous clinical trials after
the application of various breathing techniques and respiratory devices that
gradually change automatic (basal) breathing patterns at rest, reduce the degree of
hyperventilation, and increase body-oxygen levels. Generally, patients with
exertional dyspnea need to achieve more than X seconds (see below) for the
body-oxygen test to prevent dyspnea at rest and on exertion.
This number X (the result for the body oxygen test in seconds that provides a guarantee of relief from being dyspneic due to all types of exertions) is provided right below here as your bonus content.
Tweet or Share this page to reveal the bonus content.
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