Durand F, Delample D, Poulain M, Préfaut C
Laboratoire Sport, Santé, Altitude, Département STAPS l'Ermitage, Font-Romeu, France.
Rev Mal Respir. 2007 May;24(5):591-8. doi: 10.1016/s0761-8425(07)91126-2.
Exercise-induced desaturation is a well-described phenomenon in COPD patients during exercise assessments such as the six minute walk test (6MWT). Some of the pathophysiological mechanisms involved in this O2 desaturation could be modified by individualized exercise training as part of a pulmonary rehabilitation programme. The aim of this study was to determine the effect of pulmonary rehabilitation on O2 desaturation exhibited by COPD patients during a 6MWT.
Twenty COPD patients (FEV1=61.1 +/- 3.2% predicted) who exhibited O2 desaturation before rehabilitation (mean 7.3 +/- 0.7% with a mean duration of 5.3 +/- 0.1 min) participated. They performed four weeks of RP including individualized whole-body exercise training achieving a mean 9.3 +/- 0.27 hours per week of exercise tailored to their ventilatory threshold.
Dyspnoea at the end of the test, ventilatory threshold and FEV1 were retained as correlates of desaturation before rehabilitation. After rehabilitation, 6MWT distance increased (p<0.01) with reduced dyspnoea (p<0.05). Two sub-groups were identified: persistent desaturaters (DS, n=13) and non-desaturaters group (NDS, n=7). There were no baseline differences between the two groups. After rehabilitation only the persistent desaturaters showed a significant increase in distance achieved during 6MWT associated with a reduced dyspnea (p<0.05). This group showed a mean O2 desaturation equal to 8.1 +/- 0.9% which persisted to 5 +/- 0.3 min. A tendency to a lower dyspnoea at the end of 6MWT performed before rehabilitation was observed in NDS compared with DS (p<0.058).
It seems that responses to a pulmonary rehabilitation programme including individualized exercise training could act on O2 desaturation. Indeed 7 of 20 (35%) COPD patients exhibiting O2 desaturation during a 6MWT showed no O2 desaturation after rehabilitation programme while 13 on 20 (65%) do it.
运动诱发的血氧饱和度下降是慢性阻塞性肺疾病（COPD）患者在运动评估（如六分钟步行试验[6MWT]）期间一种已被充分描述的现象。作为肺康复计划一部分的个体化运动训练可能会改变这种氧饱和度下降所涉及的一些病理生理机制。本研究的目的是确定肺康复对COPD患者在6MWT期间表现出的氧饱和度下降的影响。
20例在康复前出现氧饱和度下降（平均7.3±0.7%，平均持续时间5.3±0.1分钟）的COPD患者（预测FEV1=61.1±3.2%）参与研究。他们进行了为期四周的康复训练，包括个体化的全身运动训练，平均每周达到9.3±0.27小时，根据他们的通气阈值进行调整。
试验结束时的呼吸困难、通气阈值和FEV1被保留为康复前氧饱和度下降的相关因素。康复后，6MWT距离增加（p<0.01），呼吸困难减轻（p<0.05）。确定了两个亚组：持续血氧饱和度下降组（DS，n=13）和非血氧饱和度下降组（NDS，n=7）。两组之间在基线时无差异。康复后，只有持续血氧饱和度下降组在6MWT期间达到的距离显著增加，同时呼吸困难减轻（p<0.05）。该组的平均氧饱和度下降等于8.1±0.9%，持续5±0.3分钟。与DS组相比，NDS组在康复前进行的6MWT结束时呼吸困难有降低的趋势（p<0.058）。
似乎对包括个体化运动训练的肺康复计划的反应可能会对氧饱和度下降产生影响。事实上，20例在6MWT期间出现氧饱和度下降的COPD患者中有7例（35%）在康复计划后未出现氧饱和度下降，而20例中有13例（65%）出现了这种情况。
