【摘要】 介绍了用力呼气肺量图高肺容积部分平均通过时间(MTTp-h)的测定方法,并对100例正常人和94例气道阻塞疾病(支气管肺癌、喉癌和慢性支气管炎)患者进行了测定。初步认为MTTp-h对检测大气道和上气道阻塞敏感性较高,可作为协助临床诊断的实验室指标。更多还原

【Abstract】 This paper presents a method to deter-mine the partial mean transit time of highlung volumes （MTTp-h） in the forced expi-ratory spirogram. The 12.5-50% FVC portionwas selected on the volume-axis and dividedinto 6 equal parts for calculating MTTp-h bythe formulaMTT=1/n〔t_n/2+(∑₁^n-1t)〕.One hundred normal subjects tested showeda positive correlation to FVC and the linearregression equation was formulated as:MTTp-h （sec）=0.0888+0.0068×FVC（litre）.Ninety-four cases of airway obstructiondiseases including bronchogenic carcinoma,throat carcinoma and chronic bronchitis weretested by MTTp-h and V₇₅, FEV₁/FEV0.5.The results showed that MTTp-s was themost sensitive parameter in detecting thelarge airway obstruction and upper airwayobstruction. In throat carcinoma, centraltype carcinoma of the lung and chronicbronchitis during acute attacks the MTTp-habnormality rates were 85.7%, 81.8% and 69.2%respectively, which were much higher thanby V₇₅ and FEV₁/FEV_0.5. During forcedexpiration of high lung volumes the equalpressure point was usually in the large air-way. In large airway obstruction the equalpressure point migrated upwards to thelarge airways, then the turbulent resistanceand accelerative resistance from the upstreamairways would increase resulting in the pro-longation of MTTp-h.更多还原