呼吸模式和通气效率对慢性阻塞性肺疾病运动耐力的影响

Effect of breathing pattern and ventilatory efficiency on exercise performance in chronic obstructive pulmonary disease

目的 :探讨慢性阻塞性肺疾病 (COPD)运动中呼吸模式和通气效率的变化情况及其对运动耐力的影响。方法 :32例中度COPD稳定期患者及 2 9例年龄及性别匹配的健康对照者接受了递增型心肺运动试验检测 ,对受试者在静息和最大运动负荷状态下的摄氧量 (V· O2 )、CO2 排出量 (V· CO2 )、运动功率 (WR)、无氧阈、分钟通气量(V· E)、通气效率 (V· E/V· CO2 )、潮气量 (VT)、呼吸频率 (fR)以及其它与呼吸模式相关的检测数据进行了研究分析。结果 :最大运动时 ,COPD组最大V· O2 显著降低 (P <0 .0 0 1)。COPD组与健康对照组比较 ,呼气时间显著延长 ,分别为 (1.2 1± 0 .0 4 )s和 (1.0 4± 0 .0 3)s(P <0 0 1) ;最大V· E分别为 (36 .1± 1.8)L/min和 (5 3.0± 2 .5 )L/min(P <0 0 0 1)、最大VT分别为 (1.2 8± 0 .0 5 )L和 (1.71± 0 .0 8)L(P <0 0 0 1) ,吸气时间与呼吸周期比 (0 .4 4± 0 .0 1)vs (0 .4 7± 0 .0 1)显著降低 (P <0 0 0 1) ,最大运动负荷时V·E/V· CO2 显著增高 (32 .4± 1.4vs 2 7.3± 1.0 ,P<0 0 1)。结论 :呼吸模式改变和通气效率降低是导致COPD运动耐力下降的因素之一。

Objective: To evaluate the effects of breathing pattern and respiratory efficiency on exercise capacity in patients with chronic obstructive pulmonary disease (COPD). Methods:Maximal cardiopulmonary exercise testing (CPXT) was performed in 32 patients with COPD and 29 age-and sex-matched control subjects. O_ 2 -uptake ( V· O_ 2 ),CO_ 2 -output ( V· CO_ 2 ),work rate (WR),anaerobic threshold,minute ventilation ( V· _ E ),ventilatory efficiency ( V· _ E / V· CO_ 2 ),tidal volume (V_ T ),respiratory frequency (f_ R ),and other parameters related with breathing pattern were measured used by CPXT both at rest and peak of exercise in each subject. Results: At peak of exercise,maximal V· O_ 2 was significantly decreased in COPD ( P <0.001). Compared with control subjects,COPD had longer expiratory time (1.21±0.04s vs 1.04± 0.03s,P <0.01),lower V· _ E (36.1±1.8L/min vs 53.0±2.5L/min,P <0.001),maximal V_ T (1.28±0.05L vs 1.71±0.08L,P <0.001),and the ratio of T_ I to total respiratory time (0.44±0.01 vs 0.47±0.01, P <0.001). At peak of exercise,V· _ E / V· CO_ 2 was significantly higherinCOPDgroupthanthatincontrols(32.4±1.4 vs 27.3±1.0,P <0.01). Conclusion: The changed breathing pattern and lower respiratory efficiency were important factors in damaged exercise performance in COPD.