For some time, I've been bothered by my supplemental oxygen causing a general malaise and increased breathlessness; finally, today, searching for an answer to this ongoing problem, I came across this site and am passing it and a 'blurb' along for others' interests
This sentence, in particular caught my attention, " Some people with stable Chronic Obstructive Pulmonary Disease (COPD) can manage with a higher CO2 level than people with healthy lungs":
lungfoundation.com.au/carbo...
"...A high CO2 level is usually an indication that the lungs are not able to keep up with the body’s needs. In a healthy person, a high CO2 level can occur suddenly during an acute illness. Some people adapt over time to a new “baseline” where the CO2 level in the body is higher than in healthy lungs. Some people with stable Chronic Obstructive Pulmonary Disease (COPD) can manage with a higher CO2 level than people with healthy lungs
....How does oxygen cause hypercapnia?
...Too much supplemental oxygen can cause or worsen hypercapnia by a number of different mechanisms including:
1. Dramatically changing the relationship between air exchange within the lungs and blood flow within the lungs, resulting in reduced removal of CO2.
2. Reducing the “drive to breathe”. People with healthy lungs rely on high CO2 levels to stimulate the brain to breathe. People with COPD and high CO2 levels may become “less sensitive” to a high CO2 level. The person then relies more on low oxygen levels to stimulate their breathing. Giving too much oxygen removes this stimulus to breathe, and thus reduces the removal of CO2 from the lungs.
3. Both oxygen and CO2 bind to the haemoglobin in the red blood cells. Giving too much oxygen can push the CO2 from the haemoglobin into the bloodstream, causing CO2 levels to rise in the blood.
Uncontrolled oxygen therapy, or receiving too much oxygen, can make people who usually have higher CO2 levels retain more until it reaches dangerous levels.
Some people with low oxygen levels are prescribed supplemental oxygen at home as a long-term treatment for their lung condition. In this instance, the treating physician usually determines the oxygen flow within an acceptable range. It is important that oxygen therapy is used to maintain blood levels within this acceptable range and not in an effort to reduce perceived breathlessness. Breathlessness in COPD is rarely due to low oxygen levels alone. If someone experiences worsening breathlessness they need to see their doctor and address the possible causes. Patients should not increase the oxygen flow simply to treat the symptom of breathlessness..."