Comparación caída de la saturación arterial de pulso de oxígeno (SpO2) en enfermedad pulmonar crónica, mediante sit to stand y prueba de marcha 6 minutos

Abstract

Introduction: Chronic pulmonary diseases (CLD) are characterized by intolerance to physical exercise and exertional hypoxemia, which is evaluated by the 6-minute walking test (6MWT). Currently, the Sit to stand 1-min test (STS1m) is proposed as an alternative to measure desaturation with exer­cise. Objective: Compare the STS1m with respect to the 6MWT in relation to the drop in pulse oxygen saturation (SpO2) in patients with CLD. Methods: Data were collected from patients who were part of the Pulmonary Rehabilitation Program of Clínica Universidad de los Andes (PRP-CUANDES). The subjects had no physical limitations regarding locomotor effort. Each subject performed two tests (6MWT and STS1m) comparing isotime and recording the nadir using Rad-5^® Massimo-SET^® Pulse Oximetry. Approved by the UAndes Ethics Committee (Folio: CEC2023094). A retrospective analysis of clinical records was carried out (May 2022 - August 2023). Statistical analysis: Wilcoxon test and Intraclass Correlation Coefficient (ICC). Results: Of 89 participants, 60% presented Interstitial Lung Disease (ILD) and 87% performed measurements without additional oxygen. The median nadir SpO2 with STS1m was 93 [82-99], while with PM6min was 86 [67-98]. When comparing the drop in SpO2, significant differences (p < 0.001) and only moderate internal agreement were observed when evalu­ating the ICC between STSlmin and 6MWT (ICC/aCronbach = 0.755), in the same way as in the series with ILD and O2 use (p < 0.001; ICC/aCronbach = 0.768). Conclusions:In PRP-CUANDESpatients, STS1m would not be completely comparable with PM6min in relation to the drop in SpO2. This suggests that it would be controversial to use the STS1m as a replacement tool for the 6MWT because it could underestimate information regarding users’ desaturation, independent of the baseline CLD and O2 use.