From the Guidelines
Physical therapy should be stopped if oxygen saturation falls below 90% to prevent significant hypoxemia and ensure patient safety. This threshold is crucial because oxygen saturation levels under 90% can lead to inadequate oxygen delivery to tissues and organs during increased physical demands of therapy 1. For patients with chronic respiratory conditions who normally maintain lower baseline saturations, their individual target may be adjusted by their healthcare provider, but therapy should typically be paused if saturation drops more than 4-5% below their baseline.
During physical therapy sessions, clinicians should continuously monitor oxygen levels, especially in patients with cardiopulmonary conditions, and implement rest periods if saturation begins to decline 1. If oxygen levels don't recover to acceptable levels with rest, the session should be terminated and medical evaluation may be necessary. The British Thoracic Society guideline recommends a target SaO2 of 94-98% for most hypoxaemic patients, with a 4% margin of safety to allow for variability in oxygen saturation levels 1.
Key considerations for physical therapy include:
- Continuous monitoring of oxygen levels
- Implementing rest periods if saturation begins to decline
- Terminating the session if oxygen levels don't recover to acceptable levels with rest
- Adjusting individual targets for patients with chronic respiratory conditions
- Maintaining a safe oxygen saturation level above 90% to prevent significant hypoxemia and ensure patient safety 1.
From the Research
Safe Oxygen Saturation Levels During Physical Therapy
- The safe oxygen saturation level below which physical therapy should be stopped is not strictly defined, but several studies provide guidance on this issue 2, 3, 4, 5, 6.
- A study published in the Brazilian journal of physical therapy found that 87 programs (73%) prescribed oxygen during exercise training to maintain SpO2 above a threshold ranging from 80-88% 2.
- Another study published in the American journal of respiratory and critical care medicine found that nonhypoxemic COPD patients who received supplemental oxygen during exercise training had higher exercise tolerance and improved exercise capacity compared to those breathing air 3.
- The study also noted that the patients' exercise SaO2 was greater than 88% 3.
- A review article published in Current opinion in pulmonary medicine suggested that a conservative approach to supplemental oxygen therapy could improve outcomes in patients with COPD, and that automated oxygen administration devices might reduce dyspnea during exercise and COPD exacerbations 4.
- The article also noted that the adverse effects of long-term oxygen therapy, such as reduced mobility and social stigma, need to be considered 4.
- Another review article published in Seminars in respiratory and critical care medicine discussed the physiological effects and clinical benefits of oxygen therapy in patients with COPD, and evaluated the evidence supporting and arguing against its use 5.
- The article noted that oxygen therapy has been an integral part of the management of severely hypoxemic patients with COPD for more than 50 years, despite the lack of full understanding of its effects and the relative paucity of clinical evidence supporting its use 5.
- A review article published in Clinics in chest medicine summarized the current evidence for benefits of supplemental O2 therapy during exercise in patients with COPD, and reviewed the physiologic mechanisms underlying published observations 6.
Oxygen Saturation Thresholds
- Based on the available evidence, it appears that an oxygen saturation level of 80-88% is a commonly cited threshold for prescribing supplemental oxygen during exercise training in patients with COPD 2.
- However, it is essential to note that individual patient needs and responses to supplemental oxygen therapy may vary, and that a conservative approach to oxygen therapy may be beneficial in reducing adverse effects 4.