吸入支气管舒张剂对慢性阻塞性肺疾病患者呼吸力学的影响

Effects of inhaled bronchodilators on respiratory mechanics in patients with chronic obstructive pulmonary disease

目的评价吸入支气管舒张剂对中重度慢性阻塞性肺疾病(COPD)患者平静呼吸状态呼吸力学的影响。方法20例中重度COPD患者分别在基础状态和吸入安慰剂30 min后测定基础肺功能、主观呼吸困难评分(Borg score)、呼吸方式和呼吸力学指标后,病例分成三组:Ⅰ组吸入沙丁胺醇400μg 15 min后,Ⅱ组顺序吸入异丙托溴铵80μg 30 min后和吸入沙丁胺醇400μg 15 min后,Ⅲ组顺序吸入沙丁胺醇400μg 15 min后和吸入异丙托溴铵80μg 30 min后,分别重复上述指标测定。结果与安慰剂对照,吸入支气管舒张剂后,三组肺功能指标(FEV1、FVCI、C)增加(P<0.05),跨膈压(Pdi)、食道压(Peso)、跨膈压压力时间乘积(PTPdi)、食道压压力时间乘积(PTPeso)和气道阻力(Raw)均明显减少(P均<0.05);PTPeso的减少与Peso和Raw的减少呈显著正相关(r分别为0.713和0.602,P均<0.01);三组主观呼吸困难评分降低(P<0.05),呼吸困难(Borg score)减轻与吸气做功(ΔPTPeso%)和Raw的减少(ΔRaw)呈正相关(r分别为0.339和0.358,P均<0.05),与肺功能的变化无显著相关性。结论吸入支气管舒张剂可以降低COPD患者吸气做功和气道阻力,吸气做功的减少与气道阻力减少有关。支气管舒张剂能通过减少气道阻力和吸气做功减轻COPD患者呼吸困难症状。

Objective To evaluate the effects of inhaled bronchodilators on respiratory mechanics in moderate and severe chronic obstructive pulmonary disease（COPD） patients during eupnea. Methods Twenty moderate to severe COPD subjects were divided into three groups. Lung function, Borg score, breathing pattern and respiratory mechanics indexes were measured at baseline and 30 min after inhaled placebo, salbutamol 400 μg（or ipratropium 80 μg） ,and ipratropium 80 μg（or salbutamol 400 μg） in sequence at interval as specified in different groups. Results In all groups, inhaled bronchodilators improved lung fimction （ FEV1, FVC, IC） （ P 〈 0.05）, decreased Pdi, Peso, PTPdi, PTPeso and Rsw （ P 〈 0.05, respectively）, in comparison with placebo. The reduction of PTPeso was positively correlated with the reduction of Peso（ r = 0.713, P 〈 0.01 ）and Rsw（ r = 0.602, P 〈 0.01 ）. Borg score decreased after inhaled bronchodilators （ P 〈 0.05 ）. The reduction of dyspnea （ Borg score） was positively correlated with the reduction of inspiratory work of breathing（△PTPeso% ）（ r = 0.339, P 〈 0.05）and Rsw（△Rsw） （ r = 0.358, P 〈 0.05） ,while was not associated with the changes of FEV1, FVC and IC. In COPD patients, inhaled bronchodilators can reduce inspiratory work of breathing and airway resistance, the reduction of inspiratory work of breathing contributes to the reduction of airway resistance. Alleviation of dyspnea by inhaled bronchodilators is suggestedto be ascribed to the reduction of airway resistance and inspiratory work of breathing.