Beardsmore C S, Park A, Wimpress S P, Thomson A H, Simpson H
Department of Child Health, University of Leicester, England.
Pediatr Pulmonol. 1989;6(4):223-31. doi: 10.1002/ppul.1950060403.
The flow-volume profile of a maximum voluntary cough resembles that of a maximum expiratory flow-volume (MEFV) curve with superimposed transient peak flows at the onset of each cough effort and portions of zero flow corresponding to periods of glottis closure. A straight line (the cough slope) can be drawn through the transient peak flows, and the ratio of MEFV-equivalent flow to the cough peak flow can be calculated. This cough ratio has been shown to fall during adult life and may be related to changes in airway compliance and cross-sectional area with age. The present study investigated the cough ratio, cough slope, and maximum flows measured from the cough flow-volume curve in a group of normal children aged 7 to 16 years. Maximum flows and the cough slope increased with height, but the cough ratio did not change with growth or age. In a similar group of asthmatic children, baseline measurements of cough showed a reduction in cough peak flow rates, MEFV-equivalent flow, and the cough ratio. These changes are related to alterations in airway compliance and cross-sectional area and are partly reversed following inhalation of a bronchodilator.
最大自主咳嗽的流量-容积曲线类似于最大呼气流量-容积（MEFV）曲线，在每次咳嗽用力开始时叠加有短暂的峰值流量，且零流量部分对应于声门关闭期。可以通过短暂的峰值流量绘制一条直线（咳嗽斜率），并计算MEFV等效流量与咳嗽峰值流量的比值。已表明该咳嗽比值在成年期会下降，并且可能与气道顺应性和横截面积随年龄的变化有关。本研究调查了一组7至16岁正常儿童的咳嗽比值、咳嗽斜率以及从咳嗽流量-容积曲线测得的最大流量。最大流量和咳嗽斜率随身高增加而增加，但咳嗽比值不会随生长或年龄而变化。在一组类似的哮喘儿童中，咳嗽的基线测量显示咳嗽峰值流速、MEFV等效流量和咳嗽比值降低。这些变化与气道顺应性和横截面积的改变有关，并且在吸入支气管扩张剂后部分得到逆转。
