COPD患者呼吸驱动和呼吸肌力对静息状态与最大运动时呼吸困难的影响

Study on respiratory center drive and respiratory muscle strength and dyspnea during static and exercise in patients with chronic obstructive pulmonary disease

目的探索慢阻肺(COPD)患者的呼吸中枢和呼吸肌的功能状态,明确COPD患者静息和运动时呼吸困难和动脉血氧含量的改变。方法对20例COPD患者和20例健康对照者测定静态肺功能,检测最大吸气压力和最大呼气压力及0.1 s口腔压力(P_(0.1)),行运动负荷试验。以BS评价受试者的呼吸困难,以经皮无创血氧仪测定受试者的血氧饱和度。结果COPD组的PI_(max)为(4.9±2.2)kPa,低于健康人组的PI_(max)(7.2±2.5)kPa(P<0.05),PE_(max)为(7.3±3.8)kPa,与健康人组的PE_(max)(7.6±3.4)kPa没有差别(P>0.05);P_(0.1)为(0.38±0.13)kPa,高于健康人组的P_(0.1)(0.25±0.08)kPa(P<0.05)。COPD组的BSrest为(2.2±1.7),高于健康人组的BSrest(0±0)(P<0.01),BS_(max)为(6.8±1.7),高于健康人组的BS_(max)(3.2±1.6)(P<0.01);SpO_2 rest为(92±6)%,低于健康人组的SpO_2 rest(95±3)%(P<0.05),SpO_2_(max)(86±3)%明显低于健康人组的SpO_2_(max)(92±2)%(P<0.01)。结论COPD患者不仅存在着肺部阻塞性通气功能降低,也存在呼吸中枢异常和呼吸肌功能降低。COPD患者在最大运动时呼吸困难指数高于健康人,并存在体内氧含量的缺乏。

Objective Chronic obstruetiue pulmonary diseace （COPD） is characterized by not only a lung disease but also a systemic disease. The aim of this study was to explore respiratory center drive, respiratory muscle function, dyspea, and arterial oxygen content in patients with COPD under static and exercise status. Methods Twenty patients with COPD and 20 healthy controls were recruited in this study. Static pulmonary function and exercise test were performed; P0.1, PImax were measured at rest status; BS and SpO2 were measured at both rest and maximum exercise time point. Dyspnea was assessed by the Borg Scale （BS）. Arterial oxygen saturation was measured by non-invasive method. Results PImax in patients with COPD was significantly reduced, compared with healthy controls [ （4. 9±2. 2） vs （7.2±2.5） kPa,P 〈0.05] ; there was no significant differencet in PEmax between patients with COPD and healthy controis [ （7.2±2.5 ） kPa vs （ 7.6±3.4） kPa, P 〉 0.05 ] ; P0.1 in patients with COPD was significantly increased, compared with healthy controls [ （0.38±0. 13） kPa vs（0.25±0.08 ） kPa, P 〈 0.05 ]. BS rest in patients with COPD was significantly higher than that in healthy controls [ （2.2±1.7 ）vs（0±0）, P 〈 0.05 ] ;and BSmax in patients with COPD was significantly higher than that in healthy controis [ （6.8±1.7） vs （3.2±1.6）, P 〈 0.05 ]. In addition, SpO2 rest in patients with COPD was （92±6） %, while SpO2 rest in healthy controls was （95±3 ）%, with significant difference（ P 〈 0.05 ） ; SpO2max in patients with COPD was significantly reduced, compared with healthy controls [ （86±3）%vs（92±2）%, P 〈0.051. Conclusion In patients with COPD,there not only exists the reduction of respiratory function due to obstructive limitation of airway but also exist abnormal respiratory center and decreased function of respiratory muscle. These compose an integrated reason of reduction of exercise capacity in patients with COPD. Their dyspnea index is significantly higher than that of healthy controls under maximum exercise status,and there is a reduction of arterial oxygen content in the patients.