What Are the Benefits of Pulse Oximetry?

Dr. Richard Levitan, MD, says that the use of home finger pulse oximeters by patients with COVID-19 could preempt the precipitous oxygen desaturation that leads to a crisis that needs intensive care.

Pulse oximetry is a quick, noninvasive test that measures the oxygen level (oxygen saturation) in the blood. It is an easy, painless method to measure how well oxygen is carried to parts of the body furthest from the heart, such as the arms and legs. The pulse oximeter is a clip-like device that is attached to a body part, such as a finger or ear lobe. This device uses light to measure how much oxygen is in the blood. This information helps to know if a person needs extra oxygen. It can show whether the heart and lungs are supplying sufficient oxygen through your body. 

Pulse oximeters are useful for people who have conditions that affect blood oxygen levels. pulse oximetry can help:

• Monitor oxygen saturation over time
• Alert to dangerously low oxygen levels, particularly in newborns
• Offer peace of mind to people with chronic respiratory or cardiovascular conditions
• Assess the need for supplemental oxygen
• Monitor oxygen saturation levels in people under anesthesia
• Indicate dangerous side effects in people taking drugs that affect breathing or oxygen saturation.
• Determine the effectiveness of breathing interventions, such as oxygen therapy and ventilators
• Doctors to assess the safety of the patient during physical activity or exercise (e.g., in people with cardiovascular or respiratory problems)

A doctor may also use pulse oximetry as part of a stress test. Pulse oximeters are used in infants in neonatal intensive care units to help staff alert if there is a drop in oxygen saturation. These devices help patients who are at risk of sudden infant death syndrome (SIDS) and sleeping accidents.

The purpose of pulse oximetry is to check how well a heart is pumping oxygen through the body. It may be used to monitor the health of individuals with any type of condition that can affect blood oxygen levels, especially while they’re in the hospital. These conditions include:

• Lung disease like chronic obstructive pulmonary disease (COPD), asthma, pneumonia, and lung cancer
• Anemia
• Heart diseases like a heart attack or heart failure and congenital heart defects

Moreover, pulse oximetry helps to:

• assess how well a new lung medication is working
• evaluate how a ventilator is working for ventilator-dependent patient
• monitor oxygen levels during or after surgical procedures that require sedation
• determine how effective supplemental oxygen therapy is, especially when treatment is new
• assess the individual’s ability to tolerate increased physical activity.
• evaluate whether individual momentarily stops breathing while sleeping (like in cases of sleep apnea during a sleep study)

Pulse oximetry is usually an accurate test. It consistently provides results within a 2% difference either way of what it truly is. If a reading was 82%, for example, the true oxygen saturation level may be anywhere from 80% to 84%. However, the quality of the waveform and assessment of the individual must be considered. Factors such as movement, temperature, or nail polish can impact accuracy. Typically, more than 89% of blood should be carrying oxygen. This is the oxygen saturation level needed to keep cells body healthy. An oxygen saturation level of 95%is considered normal for most healthy individuals. A level of 89% indicates potential hypoxemia or deficiency in oxygen reaching tissues in the body.