What is Oxygen?
You only have to inhale and exhale to appreciate the vital importance of oxygen in everyday life. The third most abundant element in the universe after hydrogen and helium, oxygen is an odorless, colorless and tasteless gas at room temperature and a key catalyst in many chemical reactions. Because it’s everywhere and invisible in its gaseous state, oxygen is often dismissed as being dull and inert when in fact, it’s the most reactive of all the non-metallic elements.
Oxygen makes up about 21% of the earth’s atmosphere. It is highly reactive and can combine with just about anything to create a variety of compounds. Fire, for example, is born out of a chemical reaction between oxygen and some sort of fuel, such as wood or gasoline, and a heat source, such as matches or friction. When certain metals react with oxygen they form oxides, such as iron oxides, commonly referred to as rust. Rust is a multi-million dollar problem around the world damaging bridges, buildings, engines, tools and pipes.
Yet oxygen is life-sustaining as well; without it, most living organisms would die within minutes. It releases energy from nutrients in every living cell in a process called cellular respiration. One type of oxygen – ozone – forms a thin, protective layer around the earth that shields us from the harmful effects of the sun’s ultraviolet radiation. Oxygen is pumped back into the environment through photosynthesis, a process carried out by all green plants. It’s also a component of hundreds of thousands of organic compounds.
The Discovery of Oxygen
Oxygen was first discovered in 1771 by Carl Wilhelm Scheele, a German-Swedish pharmaceutical chemist who generated what he coined as “fire air” by heating mercuric oxide, silver carbonate, magnesium nitrate and other nitrate salts. Because he neglected to publish his results until 1777, the discovery of oxygen is often incorrectly attributed to Joseph Priestley, an 18th-century theologian and chemist who isolated oxygen as a colorless gas by heating red mercuric oxide, a process that he noted caused a candle to burn brighter. Priestley published his generation of oxygen in 1774, 3 years after Scheele’s discovery, but 3 years before Scheele’s discovery went to press.
In 1775, Antoine Lavoisier repeated Scheele’s and Priestley’s experiments using more advanced laboratory equipment and naming the odorless gas “oxygen.” Lavoisier would go on to become known for advancing scientific knowledge of the chemical nature of oxygen and its role in normal breathing.1
Oxygen’s Role in Early Medicine
It wasn’t long after the discovery of oxygen that its potential value to patients with respiratory conditions became well-recognized. In 1798, Thomas Beddoes opened the Pneumatic Institute in Bristol, England where he used oxygen and nitrous oxide to treat asthma, congestive heart failure and other ailments. The first oxygen cylinders were developed in 1868, which allowed oxygen to be used in general anesthesia. By 1885, George Holtzapple used oxygen to treat a young patient with pneumonia, establishing its role in acute care.
During the 20th century, the use of oxygen in medicine became increasingly prevalent due to a rapid succession of discoveries and technical advances. In 1907, Arbuthnot Lane devised rubber tubing that served as a rudimentary nasal cannula for the administration of oxygen. Around the same time, John Scott Haldane developed designs for a modern day oxygen mask. In the 1920s, Leonard Hill invented the oxygen tent which was later modified by Alvan Barach. In 1936, Barach laid the foundation for the use of oxygen in chronic lung disease and went on to design the first portable oxygen device for emphysema. In the 1950s, Barach transfilled oxygen bottles for ambulatory patients with exertional shortness of breath while other scientists used oxygen in small, portable gas cylinders noting symptom improvement for patients with lung disease. In the 1980s, two landmark studies were foundational in establishing a survival benefit for COPD patients using continuous, long-term oxygen therapy.1
Modern Day Oxygen Therapy
Since the 1980s, the use of oxygen in clinical practice has evolved to what it is today: commonly prescribed and administered across all health care settings, even in the home. With three types of oxygen delivery systems – compressed gas, liquid oxygen and oxygen concentrators – patients are able to make choices about oxygen delivery that best suit their individual needs.
With the advent of the ultra-lightweight oxygen concentrator, traveling with oxygen is far more practical and realistic for many patients requiring continuous oxygen. What’s more, single solution oxygen concentrators like the Inogen One G5 are capable of satisfying all your oxygen needs whether you require oxygen in the home or on the go.
Who Needs Oxygen Therapy
Although many people who experience shortness of breath require oxygen therapy, shortness of breath is not the qualifying factor that gives rise to its need. Before you’re given a prescription for oxygen, your doctor will order an arterial blood gas study or conduct a pulse oximetry test to measure the amount of oxygen in your blood. Generally speaking, oxygen therapy is required if your partial pressure of oxygen, as measured by an arterial blood gas study, is less than or equal to 55 mm Hg and/or your oxygen saturation level, as measured by pulse oximetry, is less than or equal to 88 percent.
For more information about oxygen therapy, talk to your primary health care provider.
 Heffner, John E. MD. “The Story of Oxygen.” Respiratory Care. Vol. No. 1 18-31. January 1, 2013.
By Deborah Leader RN, BSN, PHN