用“瞬时流速”法描记流速-容量曲线

Measuring the MEFV by "Instantaneous Velocity of Flow

目的 探索用“瞬时流速”法描记流速 -容量曲线 (MEFV )的方法和应用价值。方法 依据数学公式V1/ 2=U1/ 2 =Y2 -Y1/X2 -X1,从用力肺活量曲线 (FVC)测量“瞬时流速”描记出MEFV曲线 ,并结合闭合气量 (CV )测定 ,对 13 5例受检者结果进行分析。受试对象分健康组 (A组 )、吸烟组 (B组 )、慢性支气管炎和哮喘缓解组 (C组 )、肺气肿组 (D组 )。结果“瞬时流速”法测量误差与观测误差接近。各组与健康组比较 ,B组 :闭合容量和肺容量的百分比 (CC/TLC % )增加 ,Ⅲ相斜率升高 (P <0 0 1 P <0 0 5 ) ;C组 :CC/TLC %增加、Ⅲ相斜率升高、 5 0 %肺活量最大呼气流量 (V50 % )、 2 5 %肺活量最大呼气流量 (V2 5% )降低、V50 % /V2 5% 减低 (P均 <0 0 1) ;D组除V50 % /V2 5%外 ,CC/TLC %增加、Ⅲ相斜率升高、V50 % 、V2 5% 降低、差异具有显著性 (P均 <0 0 1)。结论 “瞬时流速”法能较快地测量并描出曲线 ,测算过程相对简便和精确 ,适于在基层医院推广 。

Objective To Study the method and its using value of 'instantaneous velocity of flow'to measure and trace MEFV.Methods A total of 135 cases was analyzed with MEFV,traced by'instantaneous velocity of flow'that was measured by FVC according to V 1/2 =U 1/2 =Y 2 -Y 1 /X 2 -X 1 and CV.The target was divided into four groups,control (A),smoker (B),chronic bronchitis and asthma relaxed (C),emphysema (D).Results The measurement bias is close to the bias observed by this method.Each group was compared with the control group,and Group B:CC/TLC% and Ⅲ phase slope increased( P <0 01, P <0 05);Group C:CC/TLC% and Ⅲ phase slope increased,and V 50% , V 25% and V 50% / V 25% decreased ( P <0 01,respectively);Group D:CC/TLC% and Ⅲphase slope increased, V 50% and V 25% decreased( P <0 01,respectively)relatvely.Conclusions This method,'instantaneous velocity of flow',can measure and trace curve quickly,and the process of measurement is relatively simple and accurate,which is worthy to be popularized in primary hospitals to prevent and monitor the pulmonary disease.