Roberts Mary M, Cho Jin-Gun, Sandoz Jacqueline S, Wheatley John R
Respiratory Ambulatory Care Service, Western Sydney Local Health District, Westmead, Australia; Ludwig Engel Centre for Respiratory Research, Westmead Millennium Institute, Westmead, Australia.
Respirology. 2015 Apr;20(3):419-25. doi: 10.1111/resp.12471. Epub 2015 Jan 20.
The 6-min walk test (6MWT) is a simple test assessing functional capacity, but concerns about risks of substantial oxygen desaturation in pulmonary patients have led to non-adherence to the standardised American Thoracic Society guideline. We evaluated the safety of the 6MWT in stable COPD patients and compared the incidence of adverse events in patients with and without substantial exertional hypoxaemia.
6MWT data were obtained for 1136 patients with moderate to very severe COPD. Demographics, adverse events, oxygen saturation (SpO2), 6-min walk distance, lung function and quality of life measures were compared between patients with substantial exertional hypoxaemia (nadir SpO2 < 85%) and those without (SpO2 ≥ 85%). Comparisons were made using Mann-Whitney U-test for continuous variables and Fisher's exact test for categorical variables.
Twenty-five patients (2.2%) had adverse events, the most common being dizziness, chest tightness, chest pain and palpitations. Substantial exertional hypoxaemia did not increase the incidence of adverse events. No significant morbidity or mortality was recorded. Patients with adverse events had lower baseline SpO2, worse quality of life scores, and higher depression and anxiety scores. However, no significant differences were seen in anthropometric data, spirometric values or SpO2 during and after the 6MWT.
Asymptomatic exertional hypoxaemia is not associated with an increased incidence of adverse events during 6MWT in COPD patients. Our data support the ATS guideline that the 6MWT should be continued in the absence of symptoms and that intermittent oximetry monitoring does not assist in preventing adverse events.
6分钟步行试验（6MWT）是一项评估功能能力的简单测试，但由于担心肺部疾病患者出现严重氧饱和度下降的风险，导致未遵循标准化的美国胸科学会指南。我们评估了6MWT在稳定期慢性阻塞性肺疾病（COPD）患者中的安全性，并比较了有和没有明显运动性低氧血症患者的不良事件发生率。
获取了1136例中度至非常重度COPD患者的6MWT数据。比较了有明显运动性低氧血症（最低SpO2<85%）和无明显运动性低氧血症（SpO2≥85%）患者的人口统计学、不良事件、氧饱和度（SpO2）、6分钟步行距离、肺功能和生活质量指标。连续变量采用Mann-Whitney U检验进行比较，分类变量采用Fisher精确检验进行比较。
25例患者（2.2%）出现不良事件，最常见的是头晕、胸闷、胸痛和心悸。明显运动性低氧血症并未增加不良事件的发生率。未记录到显著的发病率或死亡率。出现不良事件的患者基线SpO2较低，生活质量评分较差，抑郁和焦虑评分较高。然而，在6MWT期间及之后，人体测量数据、肺量计值或SpO2方面未观察到显著差异。
在COPD患者中，无症状运动性低氧血症与6MWT期间不良事件发生率增加无关。我们的数据支持美国胸科学会的指南，即在无症状的情况下应继续进行6MWT，且间歇性血氧饱和度监测无助于预防不良事件。
