Chronic obstructive pulmonary disease (COPD) is a systemic condition that causes microvascular alterations, interfering with muscle metabolism and leading to reduced oxidative capacity and exercise tolerance limitations.

To analyze the peripheral oxygenation behavior of people with COPD.

This was a cross-sectional, analytical, and quantitative study conducted with 12 individuals with COPD. The participants' peripheral oxygenation behavior was assessed using near-infrared spectroscopy (NIRS), positioned on the medial gastrocnemius muscle, while they performed a treadmill exercise test. The evaluated variables included initial saturation (StO2 initial), lowest saturation (StO2 lowest), final saturation (StO2 final), desaturation time, and desaturation rate. Data analysis was performed using the Statistical Package for Social Science (SPSS), applying the Shapiro-Wilk normality test and a significance level of 5%.

The mean age of female participants was 68.6 ± 23.0 years, and for males, it was 69.3 ± 20.0 years. In men, the values were: StO2 initial = 53.7 ±9.58%, StO2 lowest = 48.3 ± 10.9%, StO2 final = 53.4 ± 7.92%, desaturation rate = -0.03 (-0.15 – -0.01). In women, the values were: StO2 initial = 58.6 ± 4.37%, StO2 lowest = 52.2 ± 4.45%, StO2 final = 54.5 ± 4.55%, desaturation rate = -0.18 (0.67 – -0.01).

The peripheral oxygenation behavior observed in this study differs from reference values, showing numerically lower levels. These results may be attributed to the fact that people with COPD often present chronic hypoxemia, reduced muscle perfusion due to endothelial dysfunction, and lower vasodilatory capacity. Despite the low saturation values, the volunteers were able to sustain exercise, as the desaturation rate remained below the reference values for individuals without apparent pathologies.

These findings encourage further research with a larger sample size to provide a more robust analysis of oxygenation behavior. Even with low saturation, there is resistance to continuing exercise, which may contribute to more tailored treatments for this condition through peripheral exercise.