健康成年人和稳定期慢性阻塞性肺疾病患者坐位潮气呼吸状态下气流速率的变化分析

Analysis of respiratory flow pattern during tidal breathing in seated healthy adults and stable ;chronic obstructive pulmonary disease patients

目的：观察健康成年人和稳定期慢性阻塞性肺疾病（COPD）患者的潮气呼吸流速-容积曲线（TBFV）各参数的变化特征。方法15例无吸烟史的健康成年人（健康对照组）及15例稳定期COPD患者（COPD组）纳入研究，COPD组受试前8 h内未用过平喘药物。两组均接受坐位常规肺通气功能和TBFV测定，同步监测口腔压力变化。结果 COPD组肺活量占预计值百分比（VC%）、第1秒用力呼气容积（FEV1）占预计值百分比（FEV1%）、FEV1/用力肺活量（FVC）、用力呼气中期流速占预计值百分比（MMEF%）显著低于健康对照组，差异均有统计学意义（P＜0.01）。分析TBFV参数后发现，COPD组达峰容积比（VPTEF/VTE）和达峰时间比（TPTEF/TE）分别为0.18±0.08和0.20±0.08，明显低于健康对照组的0.27±0.04和0.29±0.06，差异有统计学意义（P＜0.01）。两组呼气峰流速（PTEF）、吸气峰流速（PTIF）比较差异无统计学意义（P＞0.05）。健康对照组平静呼气中晚期流速[呼出50%潮气量时的流速（TEF50）/PTEF、呼出75%潮气量时的流速（TEF25）/PTEF]显著高于 COPD 组（0.54±0.13比0.40±0.12，0.28±0.13比0.20±0.06，P＜0.01或＜0.05）。两组最大吸气口腔压（PI max）和最大呼气口腔压（PE max）比较差异无统计学意义（P＞0.05）。结论通过测定TBFV可了解不同呼吸力学特性受试者的平静呼吸状态下流速等参数的变化，并能反映呼气流速受限，经常规肺功能测定证实是可靠有效的，由于无需患者特别配合，易于推广。

Objective To observe the characteristics of respiratory airflow in healthy adults and stable chronic obstructive pulmonary disease （COPD） patients by analysis of analyzing tidal breathing flow-volume curves （TBFV）. Methods Fifteen stable moderate COPD patients （COPD group） and 15 healthy cases without smoking（healthy control group）were enrolled into the study. No bronchodilators were used in patients of COPD group 8 h before test. Pulmonary function test and TBFV in seated position were measured, and the pressure of oral cavity was monitored concomitantly. Results The levels of percentage of vital capacity （VC%）, percentage of forced expiratory volume in the first second （FEV 1）/forced vital capacity （FVC） and percentage of maximum mid-expiratory flow （MMEF%） in COPD group were significantly lower than those in healthy control group （P〈0.01）. The parameters of TBFV showed that the fraction of exhaled volume to achieve PTEF to VTE （VPTEF/VTE） and the fraction of exhaled time to achieve PTEF to TE （TPTEF/TE） in COPD group were 0.18 ± 0.08 and 0.20 ± 0.08, which werenbsp;lower than those in healthy control group： 0.27 ± 0.04 and 0.29 ± 0.06, and there were significant differences （P〈0.01）. The level of peak tidal expiratory flow （PTEF） and peak tidal inspiratory flow （PTIF） in two groups had no significant differences （P〉0.05）. The levels of tidal expiratory flow at 50%of the remaining tidal volume/PTEF （TEF50/PTEF） and tidal expiratory flow at 25%of the remaining tidal volume/PTEF （TEF25/PTEF） in healthy control group were significantly higher than those in COPD group：0.54 ± 0.13 vs. 0.40 ± 0.12, 0.28 ± 0.13 vs. 0.20 ± 0.06, P〈0.01 or〈0.05. No differences were found in peak inspiratory pressure （PI max） and peak expiratory pressure （PE max） between two groups. Conclusions The degree of airflow limitation and the effect of bronchodilator in critical patients could be evaluated by analysis of TBFV parameters. The measurement of TBFV is simple and don′t need special technique. It is worth of promoting.