Static and dynamic evaluation of respiratory muscle strength in asthmatic children and adolescents

Abstract Objectives: to evaluate static and dynamic respiratory muscle strength in children and adolescents with asthma. Methods: cross-sectional study, involving 80 children and adolescents, 40 with asthma and 40 healthy controls. Biological and clinical characteristics were analyzed. The analysis of the dynamic inspiratory muscle strength was obtained using the KH5 device of the POWERbreathe® line, while the static evaluation was performed using an analog manova-cuometer. Results: the mean obtained from the S-Index was higher in the control group compared to asthmatics (p = 0.026). There was no statistical difference between MIP values for asthmatics and predicted values (p = 0.056). The MEP results showed a significant difference between the mean of the cases and the predicted values (p = 0.000). There was a positive correlation between height and S-Index (p = 0.002 and r = 0.438). Conclusion: the present study demonstrated that the static inspiratory muscle strength (PImáx) of children and adolescents with asthma in comparison with the values predicted in the literature does not differ, however, when submitted to dynamic assessment (S-Index), it presents higher values in healthy controls. In addition, the S-Index showed a positive correlation with the child's height.

摘要 研究目的：评估哮喘儿童及青少年的静态与动态呼吸肌肌力。
方法：本研究为横断面研究（cross-sectional study），共纳入80名儿童及青少年，其中哮喘组40例，健康对照组40例。收集并分析受试者的生物学与临床特征。动态吸气肌肌力检测采用POWERbreathe®系列KH5设备完成，静态呼吸肌肌力评估则使用模拟式呼吸压力计（analog manova-cuometer）进行。
结果：对照组的S-Index均值显著高于哮喘组（p=0.026）。哮喘组的最大吸气压力（Maximal Inspiratory Pressure, MIP）与预测值无统计学差异（p=0.056）。最大呼气压力（Maximal Expiratory Pressure, MEP）的检测结果显示，病例组均值与预测值间存在显著统计学差异（p=0.000）。身高与S-Index呈正相关（p=0.002，r=0.438）。
结论：本研究证实，哮喘儿童及青少年的静态吸气肌肌力（PImáx，即最大吸气压力）与文献报道的预测值无显著差异；但在动态呼吸肌肌力评估（S-Index）中，健康对照组的指标水平更高。此外，S-Index与受试者身高呈正相关。