Pulmonary Function Tests

1. Pulmonary Function Tests Department of Respiratory medicine Zhongshan Hospital Fudan University Zhu Lei

2. The Indication for PFTs Dyspnea, chronic cough Suspectable bronchus, lung, heart, or vertebrae diseases Descending motor ability Judgment of airway hyperresponsiveness

3. The Indication for PFTs The evaluation of therapeutic efficacyin bronchial danrespiratory diseases(No therapy without check!) The investigation of community medicine and epidemiology The evaluation of risk of surgery and anaesthesia The research of occupational disease

4. Some Important Name • 肺功能测定 • Pulmonry function test －PFT • 肺功能参数 • Pulmonry function parameters －PFPs • 静态肺功能参数 • Static lung parameters • 动态肺功能参数 • Dynamic lung parameters • 动脉血气 • Artery blood gases－ABGs

5. The Content of Pulmonary Function Testing • lung volume • Ventilation Function • Gas Exchange Funtion • Gas distrubusion • Gas diffusion • Ventilation perfusion ratio • Lung shunt • Dynamic mechanism • Arterial blood gases analysis

6. Lung Capacity

7. Basal Lung Volume • tidal volume(VT) • VT×RR＝VE • Inspiratory Reserve Volume(IRV) • Expiratory Reserve Volume(ERV) • Residal Volume(RV)

8. Basal Lung Capacity • Inspiratory Capacity(IC) • Vital Capacity(VC) • Functional Residual Capacity(FRC) • Total Lung Capacity(TLC)

9. Normal Pulmonary Function • Capacity • directly measured lung capacity • indirectly measured lung capacity (the parameters including RV) • Ventilation function • forced expiratory volume and forced expiratory volume in certain second • maximal voluntary ventilation • flow-volume curve • direct measurement • CO diffusion • indirect measurement

10. The measurement of directly measured lung capacity and ventilation • 肺活量和静息通气功能 Slow Spirometry • 流速容量环 Flow-Volume Loop • 时间肺活量检查 Forced Spirometry • 每分钟最大通气量检查 MVV

11. Spirometer 1846 J. Hutchinson “VC” 1950 Tiffeneau “V (t), FVC, FEV1” 1956 Du Bois “Raw, Zosc” residual volume determinating apparatus diffusion capacity test apparatus

12. Flowmeter

13. Pneumotachygraph Lilly Type Flow Transducer

14. Static lung parameter

15. Pulmonary Ventilation Function • Expiratory Minute Ventilation(VE) • AlveolarVentilation(VA) • Maximal Ventilatory Volume(MVV) • Forced Vital Capacity(FVC) • Flow-Volume Curve(Loop)

16. Alveolar Ventilation • Gas volume from exhalerespiratory bronchiole and alveoli • Ventilation efficacy • anatomical dead space • alveolar dead space • physiological dead space(VD)

17. VA－calculation • VD PACO2－PECO2 VT PACO2－PICO2 · PACO2= PaCO2，PICO2=0 •VD PaCO2 －PECO2 VT PaCO2 •VA=VT(1－VD/VT)×RR

18. The clinical importance of VA • VA：effective ventilation •consequence of VA •PaO2↓PaCO2↑ •influencing factor •VE ↓ •alteration of respiraion pattern

19. Forced Spirometry Volume(L) TLC FEV1 FVC a b MMEF = bc / ab c RV Time(s) 0 1 2 3 4 5

20. Dynamic lung parameter • FVC • FEV1 • 绝对值占预计值的比例，反应减退的程度 • FEV1/FVC • 反映阻塞的存在 • COPD与阻塞的区别

21. Dynamic lung parameter

22. Combination Flow Volume - Spirometry

23. MVV • Measurement time 12s or 15s • MVV＝measured value＊5(or 4)

24. Operating Requirements

25. Environmental Calibration • Measurement of Environmental Parameters • BTPS autocorrection

26. Volume Calibration • Automatic volume (flow) calibration • Manual volume calibration

27. Gas calibration • CO • 原理：电化学法 • 范围：0 - 0.4 % • 分辨率：0.0002 % • 精度： 0.003% • 稳定性：< 0.0006% • He • 原理：惠斯通电桥热导式 • 范围：0 - 10 % • 分辨率：0.005 % • 精度： 0.05% • 稳定性：< 0.02%

28. Prerequisites for best function measurements to obtain reliable and reproducible parameters • subjects: • - sitting position- static lung parameters • - erect position - dynamic lung parameters • - maximal motivation • operator : • routine in operating the equipment • detailed and comprehensible instruction of the • patient before measurement • reliable and motivating instruction of the patient during the measurement

29. 影响肺功能的相关因素 • 身高、体重、年龄、种族 • 生长，老年改变 • 取预计值的80％ • FEV1/FVC和RV/TLC例外 • 体位 • 昼夜变化：早晨FEV1下降0.2升 • 妊娠：TLC /(-)；RV、FRC、VC(-) • 其它：环境因素、吸烟

30. 间接测定肺功能指标的测定方法 残气量 间接测量的参数功能残气量 肺总量 弥散 密封式氦稀释法－ 重复呼吸法 － 一口气法 测量方法氮稀释法－密闭式重复描记法 体容积描记法

31. Single Breath Method Lung Volume by SB with Helium DLCO by SB

32. Diffusion physiology 3 Steps of adiffusion 1. Distribution 2. Diffusion 3. Perfusion

33. Diffusion physiology DLCO = Inspired gas volume/mmHg/min diffuded gas amount PACO×breath hold time ＝

34. Diffusion SB

35. Diffusion by RB

36. 体表面积 年龄 体位 运动 肺容量 屏气时间 吸氧浓度 吸烟 血红蛋白 弥散功能的影响因素

37. 气体弥散的决定因素 • 呼吸膜两侧气体分压差: * 正常的通气功能 * 正常的气体分布 * 时间常数 • 气体溶解度 * 气相：CO2<O2 * 液相：CO2>O2 正常肺 CO2弥散率/O2 弥散率=20.6/1 • 气体分布 • 弥散面积、距离 • 血流量

38. Abnormal Pulmonary Function

39. Obstructive disease .

40. obstructive ventilation disorder Normal Mild Severe

41. Impertant Concept • Airway Obstrucion • Airflow Obstructin • Airflow Limitation

42. Airflow Obstruction of perapheral airway FEV1 FVC VC >FVC RV、FRC、FRC/TLC

43. Middle- perapheral airway Obstruction FEV1 FVC0 RV、FRC、FRC/TLC

44. Fixed Obstruction of Large Airway Flow FEV1 Volume VC、RV、FRC、FRC/TLC－

45. intrathoracic nonfixed obstruction of large airway Flow Vlume

46. Extrathoracic Nonfixed Obstruction of Large Airway Flow Volume

47. Restrictive Ventilation Disorder

48. Restrictive Ventilation Disorder FEV1 0 FVC FVC =VC RV、FRC FRC/TLC

49. Grade of Pulmonary Funcion mild middle severe VC (FVC) 79-60 59-40 <40 FEV1 79-60 59-40 <40 MVV 79-60 59-40 <40

50. Small Airway Dysfunction •FVC、FEV1、FEV1/FVC: Normal •FEF25~75%(MMEF)、FEF50%(V50)、 FEF25(V25) : two of three <lower limit of normal(LLN)