Today, we tend to take long term oxygen therapy, (LTOT), for granted. The Denver Group first did its pioneering research with oxygen in COPD in 1965. But, it was not until 1970 that oxygen began to be prescribed in other cities. Our first research was with liquid portable oxygen. Our original results demonstrated a reduction in pressures in the right side of the heart and reversal of excess blood production in response to the oxygen deficit. The most impressive observation, however, was the dramatically improved exercise capacity in our patients. We had encouraged walking every day during the month before the oxygen was started under research conditions. Our patients could not do much exercise without oxygen even though they tried to increase their exercise each day for an entire month. During the following month when oxygen was given, most patients could increase their exercise a great deal. They could walk more than a mile each day. The reason for increased exercise ability was increased oxygen for the heart muscle and increased oxygen in the blood, so that together, the heart and blood could carry more oxygen to tissues, including the skeletal muscles of the body. These are the factors that deal with tissue oxygen transport.
Oxygen isn't energy. It is at the end of the energy chain to receive electrons that come from the burning of foodstuffs. It is this process, known as aerobic metabolism, that results in high energy production, which is termed bioenergetics. Much of the oxygen that we consume goes to maintaining the structure and functions of cells and tissues. When oxygen depravation is severe, tissues tend to break down.
We have recently learned that exercise, with oxygen, not only improves exercise tolerance, it restores many body functions, including brain function. Some patients gain muscle mass. What is going on is improved oxygen delivery and bioenergetics, so the tissues can repair themselves and function better than without supplementary oxygen.
Today, many suppliers are providing oxygen concentrators and E-cylinder for portability in LTOT. They are doing this because they can make more money than by providing liquid portable oxygen. E-cylinders are not very convenient for exercise, as many people know. They may actually limit the patient's ability to exercise. Without exercise, tissue oxygen transfer is limited, and the reparative process made possible by oxygen and exercise cannot take place. For patients who are able to exercise, and who in fact participate in exercise and pulmonary rehabilitation, liquid portable oxygen, or small portable cylinders, easily carried by the patients, are highly preferable. The oxygen supplier cannot change a doctor's prescription. Doctors need to prescribe what is best for their patients. Patients should know their rights, and demand a portable system if they are able to ambulate, particularly outside of the home, and participate in activities of daily living. Oxygen energizes every cell in the body and restores and enhances the function of the entire system.
I will be in touch next month.
Thomas Petty, MD