What is oxygen therapy and who is it for?
Oxygen therapy is a treatment where supplemental oxygen is administered to patients through a nasal cannula. It is prescribed to help improve oxygen supply to the body so that normal arterial blood oxygen levels are maintained.
In healthy individuals, oxygen is adequately absorbed by their lungs from regular air, but certain diseases and conditions can prevent some people from absorbing enough oxygen. Some of these conditions include:
- COPD (chronic obstructive pulmonary disease)
- Late-stage heart failure
- Cystic fibrosis
- Sleep apnoea
- Other respiratory lung diseases
A health care professional will determine whether a patient requires supplemental oxygen by measuring oxygen levels in the blood through oximetry, a non-invasive testing method using transmitted light, or an arterial blood test.
If required supplemental oxygen may be prescribed. Oxygen can be delivered through various modalities, providing patients oxygen at a concentration greater than that of room air, allowing patients to acquire sufficient oxygen.
What are the goals of oxygen therapy?
The primary goal of supplemental oxygen is to maintain peripheral capillary oxygen saturation or SpO2 levels, which normally vary between 95 – 100%, so that patients’ bodies can function properly.
Oxygen therapy also helps in these ways:
- Relieves hypoxemia (low blood oxygen levels)
- Maintains adequate oxygenation of vital tissues and organs
- Help prevent carbon dioxide accumulation and hypercapnia (high blood carbon dioxide levels)
- Reduce the work of breathing
How is oxygen delivered?
If a patient's oxygen levels are assessed to be low, supplemental oxygen may be prescribed and delivered through three types of devices:
- Oxygen concentrators
- Compressed or liquid oxygen cylinders
These oxygen devices assist by providing oxygen at greater concentrations than atmospheric air which is typically 21%. This may help to lessen the work of breathing and will assist in providing more oxygen to the patient. The clinician will provide advice on how much oxygen is needed and on the appropriate flow rate at which it is delivered.
Most often, oxygen is supplied through a nasal cannula, which is made up of two plastic tubes that fit into the nostrils. In some cases, a full-face face mask or tracheal tubes can also be used if necessary.
After starting oxygen therapy, patients should attend regular checkups to ensure therapy is sufficient and beneficial.