Many Australians have some form of chronic obstructive pulmonary disease (COPD). COPD is a broad term that includes sufferers of emphysema, chronic bronchitis and chronic asthma or a combination of any of these three diseases. A chronic disease is a long-lasting condition that can be controlled but not cured.
Whilst each of the above conditions affects the body differently, often supplemental oxygen is prescribed to assist in the management of the condition and to improve the quality of life of a person.
How oxygen gets into the body
As blood circulates throughout the body, the deoxygenated blood travels through the veins to the right side of the heart via the vena cava, and is pumped to the lungs where it is oxygenated. It then returns back to the left side of the heart where the oxygenated blood leaves via the aorta (the largest artery in the body) to the brain and the remainder of the body. The deoxygenated blood returns to the heart via the veins, completing the cycle.
Arteries divide into smaller vessels called arterioles which connect to a much smaller and more extensive capillary network. It is at the capillary level that gases are exchanged. In an average adult with about 5.5 litres of blood, 70% is found in the veins with the remaining 30% distributed between the heart, arteries and capillary network.
Whilst blood itself is made up of several different types of cells, it is the role of the red blood cell to carry the oxygen to our tissues. The red blood cells make up approximately 35% of our blood. A red blood cell contains up to 250 million molecules of haemoglobin – an iron rich molecule. A single haemoglobin molecule can bind with (carry) up to four oxygen molecules.
As we breathe in, small vessels in our lungs carry the oxygen to the tissues and as we breathe out, carry Carbon Dioxide (CO2) out of the body. CO2 is a waste product of metabolism – the physical and chemical processes that occur within a living cell or organism that are necessary for the maintenance of life. Any imbalance in this process can lead to a number of serious health risks.
If a person inhales too much oxygen and is unable to exhale the carbon dioxide it can lead to a condition called hypercapnia.
The answer to the question of whether a person can overdose on Oxygen is….Yes!