关键词: 大叶性肺炎, 肺炎支原体, 常规通气, 脉冲振荡, 肺功能, 儿童

Abstract:

Objective　To analyze the pulmonary characteristics of conventional ventilation and impulse oscillometry in children with Mycoplasma infectious lobar pneumonia and the correlation between the two pulmonary function tests，and to explore the characteristics of airway responsiveness in Mycoplasma infectious lobar pneumonia and the influence of different imaging lesions on pulmonary function. Methods　A total of 120 children aged 5-14 years old with Mycoplasma infectious lobar pneumonia hospitalized from January 2018 to December 2019 in the division of Pediatric Pulmonology of Shandong Provincial Hospital Affiliated to Shandong First Medical University，the conventional ventilation and impulse oscillometry were completed during the hospitalization period，according to the different imaging lesions，the children were divided into single lobe group and multiple lobes group，analysis of pulmonary function results and clinical data were analyzed. Results　Among the 120 children，there were 95 cases in single-lobe group and 25 cases in multiple-lobe group. Normal conventional ventilation were 33 cases（27.5%） and abnormal in 87 cases（72.5%）. Among abnormal conventional ventilation the restrictive ventilation dysfunction in 43 cases，two or more of the three small airway indexes were lower than 65% predicted value was in 63 cases. In the 120 cases，impulse oscillometry test showed normal airway resistance in 106 cases（88.3%） and increased airway resistance in 14 cases（11.7%）. Airway resistance indexes are negatively correlated with ventilation indexes. 43 cases of children with FEV1 measured value/expected value<80% completed bronchodilation test，bronchodilation test was positive in 6 cases，and airway resistance was significantly improved in 11 cases. The airway resistance indexes total respiratory impedance（Z5），total airway resistance（R5），and central airway resistance（R20） of the multiple lobes group were lower than that in sigle lobe group，and peripheral elastic resistance（X5） was higher than that in single lobe group，there was no statistical difference. The conventional ventilation index vital capacity（VC），forced vital capacity（FVC），forced expiratory volume in one second（FEV1） of the multiple lobes group was lower than that in single lobe group，have significantly different between the two groups（P<0.05）. Conclusion　The children with Mycoplasma infectious lobar pneumonia mostly have restrictive ventilation dysfunction；the small airway function indexes are significantly damaged and the recovery of small airway indexes is slower than that of large airway indexes；airway resistance indexes have a good negative correlation with the expiratory flow indexes. Mycoplasma pneumoniae infection can induce increased airway responsiveness，and bronchodilation tests in some children show reversible airflow limitation and a significant improvement in airway resistance. Children with lesions involving multiple lobes had more severe reduction in lung volume，and the reduction of expiratory flow indexes was widespread in children with different lesions.

Key words: lobar pneumonia, Mycoplasma pneumoniae, conventional ventilation, impulse oscillometry, pulmonary function, child