Pulse oximetry is a test that accurately estimates the amount of oxygen circulating in the blood. Pulse oximetry is safe, quick, non-invasive, and inexpensive.
By measuring oxygen saturation levels using a fingertip pulse oximeter, it is possible to calculate whether an adequate amount of oxygen is supplied by the heart and lungs to the rest of the body for survival.
Low blood oxygen levels (hypoxemia) are associated with various diseases; however, it is difficult to observe hypoxemia until oxygen saturation is below 80%. For this reason, early detection of hypoxemia using a pulse oximeter could lead to prompt health care and treatment, such as oxygen supplementation. Critically ill patients with oxygen saturation levels of 94% or lower should be treated with oxygen delivery, which may reduce hypoxemia-related mortality rates.
A home fingertip pulse oximeter can be useful for patients with pneumonia, anemia, asthma, chronic obstructive pulmonary disease (COPD), a history or risk of heart attacks, or lung cancer to monitor oxygen saturation.
Pneumonia is the infection and inflammation of the lungs that can be caused by bacteria, viruses, fungi, or parasites. Pneumonia is the sixth leading cause of death and the largest infectious cause of mortality in the US. Symptoms include a high fever, cough, fatigue, and breathing difficulties.
Hypoxemia is a common complication of pneumonia and is a risk factor for increased mortality. Pneumonia can normally be treated with antibiotics, rest, and fluids. More severe cases may require oxygen saturation monitoring and oxygen supplementation, which has been found to considerably lower length of stay in hospitals.
Using a fingertip pulse oximeter can help with early diagnosis of pneumonia or track its progression during home care.
Anemia is a disorder caused by nutritional deficiency, associated with a lack of red blood cells to maintain normal oxygen levels in the body. Iron deficiency is the most common cause of anemia, since iron is vital for the production of hemoglobin (protein involved in oxygen transport). Common symptoms include fatigue, shortness of breath (dyspnea), and irregular heartbeats.
An oxygen saturation monitor can be used for early recognition and treatment of iron deficiency anemia by tracking blood oxygen concentrations and heart rate, particularly in teenagers and pregnant women.
In anemic patients, there is reduced oxygen delivery and, as a result, lower tissue oxygen saturation; an advantage of fingertip pulse oximeters is that they are able to provide a value for oxygen saturation even in cases of extreme anemia.
Asthma is the complete or partial reversible inflammatory obstruction of the airways, of which bronchial asthma is the most common. An acute asthma attack may improve naturally or may require specific intervention.
Since hypoxemia is a common complication of asthma, pulse oximetry may be a useful measure of the severity of acute asthma attacks (especially in children), the adequacy of oxygen therapy in patients whose oxygen saturation levels have decreased to below 92%, or in the follow-up of asthma patients.
4. Chronic Obstructive Pulmonary Disease (COPD)
Chronic obstructive pulmonary disease (COPD) is a lung disease characterised by constant restriction of airflow. COPD patients can experience low oxygen saturation, particularly during the night (nocturnal desaturation): a value lower than 92% indicates respiratory failure.
Hypoxemia can worsen with increased COPD severity and is associated with diminished quality of life, a lower tolerance to physical activity, and higher risks of complications and death.
A wearable finger pulse oximeter enables pulse rate measurements to be collected during stable phases and exacerbations of COPD; this will help patients to decide if they should go to the emergency room and whether they have a need for oxygen supplementation.
5. Heart attack patients
Heart attacks are a result of interrupted flow of oxygenated blood in the heart for a prolonged period. A common intervention is oxygen supplementation provided through nasal cannulas or face masks.
Pulse oximetry can be used to monitor heart rate and oxygen saturation, which are extremely important factors for assessing the condition of the cardiovascular system. Measuring blood oxygen levels with a home pulse oximeter can aid the diagnosis and severity of heart disease, especially when managing patients at risk of heart attacks.
6. Lung cancer
Globally, lung cancer is the most common cancer type; the majority of diagnosed patients have late-stage disease and a poor prognosis. Symptoms of lung cancer, including changes in breathing, chest pain, cough, and loss of weight or appetite, have an exceedingly negative impact on the quality of life and functionality of patients. A common prescription for advanced lung cancer is oxygen delivery due to the likelihood of hypoxemia and dyspnea.
The use of a fingertip pulse oximeter to diagnose hypoxemia in lung cancer patients can: aid the management of hypoxemia, improve the palliative care of patients, and provide a valuable assessment of lung function and pathology.
Although a home pulse oximeter cannot be used as a method of diagnosing or treating a health problem, this tool may be beneficial in the detection of hypoxemia, a common symptom in many diseases. This could also enable effective remote monitoring of patients and could accelerate the stages of diagnosis through to treatment. However, it is important to be aware of inaccurate readings (potentially due to poor signal strength or laboured breathing) and Food and Drug Administration (FDA) guidelines. You should consult your doctor in case of any concerns.
Written by Albina Babu, MSc
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