From the Guidelines
A SpO2 level of 95% during sleep is not a cause for concern and is considered within the normal range. According to the BTS guideline for oxygen use in adults in healthcare and emergency settings 1, a transient dip in saturation to 90% or less in normal participants during sleep is considered normal. The guideline recommends checking blood gases in situations where there is an unexpected or inappropriate fall in SpO2 below 94% in patients breathing air or oxygen, but a single reading of 95% does not meet this criteria.
Key points to consider:
- Normal oxygen saturation levels typically range from 95% to 100% for most healthy individuals
- Brief dips to 95% during sleep are considered normal and fall within the normal range
- Oxygen saturation naturally varies throughout the night due to changes in breathing patterns during different sleep stages
- If you consistently see levels below 90%, that would warrant medical attention as it could indicate a condition like sleep apnea or another respiratory issue
- Symptoms such as excessive daytime sleepiness, morning headaches, or gasping for air during sleep should be discussed with your healthcare provider regardless of your SpO2 readings, as they may indicate an underlying condition that needs attention.
From the Research
Understanding Mild Hypoxemia During Sleep
Mild hypoxemia, defined as an oxygen saturation of 95%, during sleep may not be a significant concern for healthy individuals.
- A study published in 1996 2 found that the mean lowest oxygen saturation recorded during the night for healthy subjects was 90.4%, and the mean saturation below which the patient spent 10% of the time was 94.7%.
- However, for patients with certain medical conditions, such as congestive heart failure, supplemental oxygen therapy should be used with caution to avoid hyperoxia, as indicated by SpO2 values >95% 3.
- Another study published in 2021 4 compared the effects of supplemental oxygen therapy and continuous positive airway pressure on patients with obstructive sleep apnea, and found that supplemental oxygen therapy was less effective in reducing apnea-hypopnea index and improving quality of sleep.
Considerations for Patients with Underlying Medical Conditions
For patients with underlying medical conditions, such as obstructive sleep apnea or coronary heart disease, the use of continuous positive airway pressure (CPAP) or supplemental oxygen therapy may be beneficial.
- A study published in 2022 5 found that CPAP therapy was associated with a reduced risk of adverse cardiovascular outcomes in patients with coronary artery disease and obstructive sleep apnea.
- Another study published in 2017 6 found that CPAP therapy improved health-related quality of life in patients with coronary heart disease or cardiovascular risk factors and obstructive sleep apnea.
- However, the use of supplemental oxygen therapy may have varying effects on different patients, and its benefits and risks should be carefully considered 4, 6.