稳定期慢性阻塞性肺疾病患者的气道阻力与运动相关呼吸困难肺功能参数的关系

目的观察稳定期慢性阻塞性肺疾病(COPD)患者的各项气道阻力(Raw)参数与运动相关呼吸困难肺功能参数的相关关系。方法前瞻性纳入上海交通大学附属胸科医院和第一人民医院门诊稳定期COPD患者180例,根据慢性阻塞性肺疾病全球倡议(GOLD 2017版)制订的肺功能诊断标准分为Ⅰ-Ⅳ级4组,受试前8 h内均未应用支气管舒张剂。所有患者在吸入沙丁胺醇400μg后接受常规肺功能和气道阻力测试。同期选择42例成年健康体检者作为对照组。结果Ⅱ级以上COPD患者的第1秒用力呼气容积和呼出50%肺活量时流量均显著低于健康成年人和Ⅰ级COPD患者,总气道阻力、有效气道阻力、吸气阻力和呼气阻力则呈进行性增高。Ⅲ-Ⅳ级COPD患者的深吸气量占预计值百分比(IC%pred)<80%,同时改良英国医学研究委员会呼吸困难量表评分超过2分;7例Ⅲ级(13.2%)和14例Ⅳ级COPD患者(33.3%)的吸气分数(IC/TLC)≤25%,而仅有1例Ⅱ级COPD患者的IC/TLC≤25%(1.9%)。结论稳定期中重度COPD患者呼出气流受限趋于加重,Raw各项参数中呼气阻力增高尤为显著。Ⅲ-Ⅳ级COPD患者更易出现运动相关呼吸困难症状,且IC/TLC≤25%。

Relationships between airway resistances and activity-related dyspnea in patients with stable chronic obstructive pulmonary disease

Objective To observe the relationship between the airway resistance(Raw)and activity-related dyspnea in patients with chronic obstructive pulmonary disease(COPD).Methods This was a prospective study with 180 patients with COPD(Global Initiative for Chronic Obstructive Lung Disease 2017 stagesⅠ-Ⅳ)who presented at the outpatient clinic of the Shanghai Chest Hospital and Shanghai general hospital,from December 2017 to March 2019.Spirometry testing and respiratory resistance components were measured by plethysmography after brochodilator(salbutamol 400μg)inhalation.Results Compared with 42 healthy elder and 30 mild COPD patients,The first second forced expiratory volume and forced expiratory flow at 50%vital capacity in patients with GOLD stagesⅡ-Ⅳwere significantly lower.The total airway resistance(Rtot),effective airway resistance(Reff),inspiratory airway resistance(Rinsp)and expiratory airway resistance(Rexp)of the moderate and severe COPD patients were significantly higher than those of the healthy elder group.The inspiratory capacity(IC)of patients with GOLD stagesⅢ-Ⅳis under 80%of the predicted value,which mMRC score was exceed 2.One patient(1.9%)with GOLD stageⅡ,7(13.2%)patients with GOLD stageⅢand 14(33.3%)patients with GOLD stageⅣrevealed inspiratory fraction(IC/TLC ratio)≤25%.Conclusions Raw,especially expiratory airway resistance were obviously increased in stable moderate to severe COPD patients on account of the severe expiratory flow limitation.According to the aggravation of peripheral airway inflammation,activity-related dyspnea symptoms were more prone to occured in COPD patients with GOLD stagesⅢ-Ⅳ,and IC/TLC ratio might more likely to be below 25%.