呼吸阻抗对慢性阻塞性肺疾病的诊断价值

目的　探讨呼吸阻抗对慢性阻塞性肺疾病 (COPD)的诊断价值。方法　用脉冲振荡法 (IOS)对 117例COPD患者进行呼吸阻抗测定并与常规肺通气功能比较。结果　COPD患者 5～ 35Hz振荡频率时黏性阻力和共振频率较健康组明显增高 ,5、35Hz时电抗明显低于健康组。COPD组除X5与常规肺通气功能指标呈显著正相关外 ,Fres、R5、R5-R2 0 均与其呈显著负相关。Fres与FEV1 pred .和FEV1 FVC %相关性最密切 ,相关系数分别为 - 0 .6 3和 - 0 .6 2。Fres诊断COPD敏感度最高 ,其次为R5、X5,并随病情加重 ,敏感度不断提高。三项指标的特异度分别为 90 .91%、95 .4 5 %和 93.18%。结论　IOS法所测COPD患者Fres、R5、R5-R2 0 、X5与传统肺通气功能指标有显著的相关性 ,其中Fres是诊断COPD最敏感的指标

The diagnostic value of total respiratory impedance for chronic obstructive pulmonary disease

Objective To study the diagnostic value of total respiratory impedance for chronic obstructive pulmonary disease (COPD). Methods The impedance of respiratory system was measured by impulse oscillometry system (IOS) and compared with parameter values of routine pulmonary ventilation function in 117 patients with COPD. Results There was a greater significant increase in viscous resistance (R) ranging from 5?Hz～35?Hz and resonant frequency (Fres) in COPD group than those in healthy group. Reactance (X) of 5?Hz and 35?Hz in COPD group was markedly lower than that in healthy group. Fres, R 5, R 5-R 20 were negatively correlated with parameters of pulmonary ventilation function; X 5 was positively correlated with parameters of pulmonary ventilation indices. A closer correlation was found between Fres & FEV 1% pred. and FEV 1/FVC%; the correlation coefficient values were -0.63 and -0.62, respectively. The sensitivity of Fres was the highest, followed by that of R 5 and X 5. The sensitivity increased continuously with the progression of the disease. The specificities of the three parameters were 90.91%, 95.45% and 93.18%, respectively. Conclusion The significant correlation exists between Fres, R 5, R 5-R 20 and X 5 & parameters of routine pulmonary ventilation function. In the parameters of IOS, Fres is the most sensitive index for diagnosis of COPD.