Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria,
Department of Thoracic Surgery, Otto Wagner Hospital, Vienna, Austria.
Respiration. 2020;99(3):225-230. doi: 10.1159/000505856. Epub 2020 Jan 31.
In moderate-to-severe chronic obstructive pulmonary disease (COPD) patients the 6-min walk test (6MWT) is often exhaustive and correlates with the incremental cycle cardiopulmonary exercise test (CPET).
The aim of this study was to assess the agreement between oxygen uptake (VO2) measured during the 6MWT by portable equipment and incremental cycle exercise in COPD patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) I-IV.
A total of 30 patients with COPD GOLD I-IV (14 patients GOLD stage I and II and 16 patients GOLD stage III and IV) underwent a 6MWT and an incremental CPET. Breath-by-breath analysis for VO2, carbon dioxide output (VCO2), and minute ventilation (VE) were measured during each test. Blood gas analysis and lactate measurements were performed before, during, and after the test.
VO2 in COPD patients GOLD stage I and II was 16.2 ± 4.2 mL/kg/min measured by 6MWT and 20.5 ± 7.0 mL/kg/min measured by CPET as compared to GOLD stage III and IV (11.2 ± 3.7 mL/kg/min measured by 6MWT and 15.5 ± 4.3 mL/kg/min measured by CPET). No significant correlation in VO2 measurements could be found between both tests in COPD GOLD I and II (r = 0.17), whereas the VO2 significantly correlated in patients with COPD stage III and IV (r = 0.7).
A significant relationship between VO2 measured by 6MWT and CPET could only be found in patients with more severe COPD but not in milder stages. 6MWT and CPET provide different VO2 measurements in COPD patients. The two methods cannot be used interchangeably.
在中重度慢性阻塞性肺疾病（COPD）患者中，6 分钟步行测试（6MWT）通常是耗竭性的，并且与递增循环心肺运动测试（CPET）相关。
本研究旨在评估便携式设备在 COPD GOLD I-IV 患者中测量的 6MWT 期间的摄氧量（VO2）与递增循环运动时的摄氧量之间的一致性。
共 30 名 COPD GOLD I-IV 患者（14 名 GOLD Ⅰ和Ⅱ期患者和 16 名 GOLD Ⅲ和Ⅳ期患者）接受了 6MWT 和递增 CPET。在每次测试中，通过呼吸对 VO2、二氧化碳输出（VCO2）和分钟通气量（VE）进行逐口气分析。在测试前后进行血气分析和乳酸测量。
与 COPD GOLD Ⅲ和Ⅳ期患者（6MWT 测量的 11.2 ± 3.7 mL/kg/min 和 CPET 测量的 15.5 ± 4.3 mL/kg/min）相比，GOLD Ⅰ和Ⅱ期患者的 VO2 分别为 6MWT 测量的 16.2 ± 4.2 mL/kg/min 和 CPET 测量的 20.5 ± 7.0 mL/kg/min。在 COPD GOLD I 和 II 中，无法在两种测试之间找到 VO2 测量值的显著相关性（r = 0.17），而在 COPD Ⅲ和 IV 患者中，VO2 显著相关（r = 0.7）。
仅在 COPD 更严重的患者中，6MWT 测量的 VO2 与 CPET 之间存在显著关系，而在更轻的阶段则没有。6MWT 和 CPET 可提供 COPD 患者不同的 VO2 测量值。这两种方法不能互换使用。
