The body needs an adequate amount of oxygen in order to function properly. There are many diseases and situations that can affect the ability of the heart and lungs to keep up with the demand. If the levels of oxygen in the blood get too low, a condition called hypoxemia may be diagnosed. In severe cases, this condition is life threatening. If there are risk factors present for this condition, a pulse oximetry machine can be used to detect if levels are normal.
Considerations
Air that is inhaled travels through the lungs and eventually into tiny sacs within the lungs called alveoli. There are blood vessels within the aveoli that pick up the oxygen so it can be delivered to the body. Oxygen can be transported through the body because the red blood cells contain a protein called hemoglobin, which is a substance that actually attaches to and carries the oxygen, states the Ohio State University Medical Center. When the hemoglobin is oxygen rich and traveling through the arteries to various areas of the body, the blood is bright red. After the oxygen is delivered to the cells and the deoxygenated blood is carried back to the heart through the veins, the blood turns blue.
Identification
To help determine how oxygen rich the circulating blood is, a machine called a pulse oximeter can be used. The reading from this machine tells how saturated the hemoglobin is with oxygen. According to the University of Texas, pulse oximetry involves attaching a devise usually onto a finger tip or any area that has a pulse. This devise transmits infrared light through body tissue and between the two sensors that are located on each side of the finger. During this procedure, most of this infrared light is absorbed by the tissue, while some of it travels through the finger. The light that travels through, can be analyzed to determine how saturated the hemoglobin is.
Benefits
There are many symptoms that can develop if the levels of oxygen get too low in the blood. This includes shortness of breath, difficulty breathing, dizziness, fainting, chest pain, muscle cramping and weakness, confusion, irritability, irregular heart rhythms, cyanosis (blueish skin) and many others, claims the State of Indiana website. By the time some of these symptoms appear oxygen levels are dangerously low. Low oxygen levels can be from disease, change in altitude, over exertion or exposure to pollutants. While pulse oximetry alone can not confirm a diagnosis, it may help to detect abnormal oxygen levels before serious symptoms appear.
Features
There are many situations that can affect the accuracy of this test, which is expressed as arterial oxygen saturation of hemoglobin, or SaO2. In general, a reading of between 97 and 99 percent is considered normal. For some patients, readings as low as 90 percent can be acceptable. However, as the reading drops to 90 percent or lower, further evaluation is needed, warns the American Association of Critical Care Nurses. Pulse oximetry readings should be used as guidelines only, as various situations can cause false or misleading readings.
Types
There are pulse oximeters that can be used at home. The Aetna website recommends speaking with a health care provider, in cases where home oxygen therapy is required or to help diagnose severe cases of chronic obstructive pulmonary disease (CPOD) or sleep apnea. Using the devise at home can help in determining the severity of any disease present, the level of treatment needed and if the treatment being used is effective. In cases where home monitoring is medically necessary, the procedure may be covered by insurance.
