Lødrup Carlsen K C
Dept of Paediatrics, Woman Child Clinic, Ullevål University Hospital, Oslo, Norway.
Monaldi Arch Chest Dis. 2000 Oct;55(5):427-34.
Measurement of lung function during tidal breathing may be performed regardless of the age and respiratory state of the patient. This is particularly advantageous in young children in whom forced respiratory manoeuvres cannot be performed, but has also been found useful in adults with various chest diseases. The most frequently reported tidal breathing parameters are mathematical expressions of the shape of the tidal flow/volume (TFV) loop or tidal flow/time traces, as the ratio of the time or volume taken to reach peak expiratory flow to total expiratory time or volume (tPTEF/tE or VPTEF/VE, respectively). However, new parameters have been suggested, focusing on the shape of the latter portion of the curve. Standardization of measurements is important, and more studies are required to settle some of the issues regarding, for instance, how many curves to evaluate, which parameter to report and how to perform challenge or reversibility tests. Intra-individual variation should be kept to a minimum, preferably performing measurements under the same conditions on each occasion. The issue of whether to sedate is a subject of debate. However, with experience, reproducible TFV measurements may be obtained in most subjects in the awake state, regardless of age, provided the setting is friendly and calm. TFV measurements have provided important information in research as well as clinical settings. Reduced tPTEF/tE has been demonstrated in newborn term and premature babies born to smoking mothers, and is a risk factor for recurrent wheeze within the first 3 yrs of life. Also, tPTEF/tE is clearly reduced in subjects with acute bronchial obstruction (BO) (such as occur in bronchiolitis), but also in asymptomatic children with BO for other reasons, such as asthma. Significant response to histamine and methacholine as well as to bronchodilator has been demonstrated in preschool children, adults and animals (horses, dogs and cats). The present paper discusses various practical issues concerning and possible uses of tidal flow/volume measurements. In conclusion, tidal flow/volume measurements may be important supplementary tools in the investigation of respiratory disease in both research and clinical work in subjects who for any reason cannot cooperate with more conventional lung function measurements.
无论患者的年龄和呼吸状态如何，均可在潮气呼吸时进行肺功能测量。这对年幼患儿尤为有利，因为他们无法进行用力呼吸动作，但在患有各种胸部疾病的成年人中也发现这种测量方法很有用。最常报告的潮气呼吸参数是潮气流量/容积（TFV）环或潮气流量/时间曲线形状的数学表达式，即达到呼气峰流量所用时间或容积与总呼气时间或容积的比值（分别为tPTEF/tE或VPTEF/VE）。然而，有人提出了新的参数，重点关注曲线后半部分的形状。测量的标准化很重要，还需要更多研究来解决一些问题，例如要评估多少条曲线、报告哪个参数以及如何进行激发或可逆性试验。个体内差异应保持在最低限度，最好每次都在相同条件下进行测量。是否使用镇静剂是一个有争议的问题。然而，凭借经验，在友好平静的环境中，大多数清醒状态下的受试者，无论年龄大小，都可以获得可重复的TFV测量结果。TFV测量在研究和临床环境中都提供了重要信息。已证实，吸烟母亲所生的足月儿和早产儿的tPTEF/tE降低，这是1岁前反复喘息的危险因素。此外，急性支气管阻塞（BO）（如细支气管炎时出现的情况）患者以及因其他原因（如哮喘）患有BO的无症状儿童的tPTEF/tE也明显降低。学龄前儿童、成年人和动物（马、狗和猫）对组胺、乙酰甲胆碱以及支气管扩张剂均有显著反应。本文讨论了与潮气流量/容积测量有关的各种实际问题及其可能的用途。总之，对于因任何原因无法配合更传统肺功能测量的受试者，潮气流量/容积测量可能是研究和临床工作中呼吸系统疾病调查的重要辅助工具。
