Does Muscle Oxygenation During The 6-Minute Walk Test in Fibrosing Lung Disease?

<bold>Introduction:</bold> The progression of fibrosis that develops with the disease increases the impairment in gas transfer, and in some fibrotic lung patients, although oxygen saturation is acceptable under resting conditions, desaturation caused by exertion can be disturbing. Oxygen desaturation contributes to dyspnea and exercise intolerance in these patients. The exercise may have effects on muscle oxygenation. <bold>Aims:</bold> The aim of the study is to investigate changes in lower limb muscle oxygenation during exercise and to determine the relationship between exercise capacity and muscle oxygenation. <bold>Methods:</bold> Muscle oxygenation was measured with "near infrared spectroscopy" placed on the vastus lateralis muscle during the 6-minute walking test (6MWT) of the subjects. Quadriceps femoris muscle strength and respiratory function values were measured. <bold>Results:</bold> The study comprised 24 cases diagnosed with fibrotic lung disease, with an average age of 64.50±10.40 years. These subjects walked an average distance of 570±147 meters. The resting SpO₂ (%) was 94.36±3.58, and the final SpO₂ (%) was 88.86±6.19. Additionally, the resting SmO₂ (%) was 41.47±19.49, and the final SmO₂ (%) was 41.56±19.90. Statistical analysis revealed no significant difference between the resting and final SmO₂ (%) at the end of the 6MWT (p=. 878). Furthermore, no correlation was observed between the 6MWT distance and the average SmO₂ (%)(p=. 895). <bold>Conclusions:</bold> As a result of our study, exercise may have a positive effect on peripheral muscle oxygenation. More studies are needed to examine the effect of exercise training on peripheral muscle oxygenation.