以婴幼儿体积描记仪建立的足月新生儿肺功能参数正常值

目的 测定新生儿肺功能参数正常值，为呼吸系统疾病的诊治和呼吸机参数的设定提供客观依据。方法 采用婴幼儿体积描记（简称体描）仪检测406名符合纳入与排除标准新生儿的功能残气量、有效气道阻力和潮气呼吸参数，体描检测后剔除正常呼吸可能受疾病干扰或不符合质量控制标准者，最终有211名呼吸生理功能正常的新生儿被纳入数据分析。根据日龄，将其分为1~7 d、~14 d、~21 d、~28 d日龄组进行比较。结果 随日龄增加，呼吸生理功能正常的新生儿身长、体重差异有统计学意义（P= 0.004,P<0.000 1），功能残气量(FRCP)、潮气量（VT）、25%和50%潮气量时的潮气呼气流速（TEF25，50）呈递增趋势，特殊有效气道阻力（sReff）、公斤体重有效气道阻力（Reff/kg）呈递减趋势，达峰时间比（TPTEF/TE） 、达峰容积比（VPTEF/VE） 、FRCP/kg、VT/kg保持相对恒定；新生儿肺容量的增加与流速的增长保持一致，小气道的发育快于大气道；新生儿肺功能的影响因素为身长、BMI、体重和日龄，相关性分析及LMS百分位数曲线图均提示体重对新生儿肺功能的影响最为显著。结论 随日龄增加，新生儿期肺容积增大，气道阻力降低，呼吸效能逐渐提高；本文建立的新生儿肺功能参数正常值可为呼吸机参数的设置、呼吸系统发育评估和疾病诊治提供参考依据。

Using baby body plethysmography to build normal reference values of lung function parameters for term infants

Objective To develop reference ranges for plethysmographic parameters for Chinese neonates and to provide the basis for diagnosis or treatment of respiratory diseases and parameters setting of ventilators. Methods There were 406 infants who met the inclusion and exclusion criteria, aged 1 -28 days, received pulmonary function tests （PFTs） which were performed in the whole body plethysmography to access plethysmographic functional residual capacity （ FRCp ）, effective air way resistance （Reff） and their tidal breathing. After PFTs, data of 195 infants were excluded from analysis as their condition might disturb the normal respiration or failed to meet quality control standard. Finally, data of 211 infants without any respiratory diseases were enrolled in the analysis. According to their age, infants were grouped into 1 - 7 d, - 14 d, - 21 d and - 28 d groups for comparison. Results For neonates, height and weight increased significantly with age （P = 0. 004, P 〈 0.000 1 ）. Values of FRCp, VT, and TEF25/50 raised with age, while values of sReff and Reff/kg declined. Values of TPTEF/TE, VPTEF/VE, FRCp/kg and VT/kg remained relatively constant with growth. The flow rate increased in step with the lung volume while small airways developed faster than big ones. Lung function of newborns was significantly associated with body length, weight, BMI and age, results of logistic regression and smoothed centiles of FRCp, VT, TEF2s indicated that body weight was the strongest predictor of lung function. Conclusion Newborns＇lung volume and efficiency of respiratory increased with growth, whereas airway resistance declined with age. The current reference ranges of plethysmographic parameters can provide basis for parameters setting of ventilators and reference for evaluating respiratory development, diagnosing or treating respiratory diseases.