Expiratory flow limitation detected by negative expiratory pressure in children with asthma / 国际儿科学杂志

ABSTRACT

Objective The purpose of this study was to evaluate the feasibility of expiratory flow limitation(EFL) detected by negative(NEP) and the correlation between EFL and routine lung function measurements(Forced expiratory volume in first second,FEV1),EFL and MRC dyspnea scale,in patients with stable and acute asthma,to find a simple,reliable and objective method for the diagnosis,differential diagnosis,the severity of disease and evaluation of severity and efficacy of treatment for asthma,and a objective method reflecting the severity of dyspnea.Methods Sixty-four children enrolled in No.306 Hospital of PLA from Jun.to Dec.in 2012 were included in this study.The severity of dyspnea was rated according to the dyspnea scale proposed by the Medical Research Council(MRC).Then routine pulmonary ventilation function tests and NEP technique were performed respectively.Result (1) All asthmatic patients tolerated NEP well.(2) Pulmonary ventilation function testsThe mean FEV1 in 64 was 71.33 ± 13.92％ pred.(3) MRC dyspnea scaleMRC dyspnea scale was 2 in 10,1 in 54 of 64 children with stable asthma.The Spearman' s correlation coefficient of MRC dyspnea scale with FEV1 was-0.635(P ＜0.05).(4)EFL detected by NEPThere were no EFL in 46 children with asthma both in seated and supine positions.There were EFL in 8 children both in seated and supine positions and in 10 only in supine position..The Spearman's correlation coefficient of three-point EFL score with FEV1 and MRC dyspnea scale was-0.607 and 0.964(P ＜ 0.05) respectively.The Spearman's correlation coefficient of five-point EFL score with FEV1 and MRC dyspnea scale was-0.626 and 0.966 (P ＜ 0.05)respectively.Conclusion (1) NEP technique can be used in children with asthma.(2) There was a significant correlation between EFL detected by NEP technique and FEV1.(3) There is a stronger correlation between EFL and MRC dyspnea scale than that between FEV1 and MRC dyspnea scale.