英文版肺功能檢查課件(PPT 50頁)

1、Pulmonary Function TestingRespiratory Department of the Second Affiliated Hospital of Guangzhou Medical University Huaxing Huang 第1頁，共50頁。History of pulmonary function testingMore than 300 years, water sealed spirometer wedged-typed spirometer drum-typed spirometer digitalized spirometerIn 1679,BORE

2、LLI measured lung volume firstly.In 1846,HUTCHINSON put forward the concept of vital capacity.In 1919,NIANSTROHL put forward the concept of forced vital capacity.In 1967,DOLLFUSS put forward the concept of disease of small airway.In 1979,ATS setup the work standards of pulmonary function testing.第2頁

3、，共50頁。第3頁，共50頁。第4頁，共50頁。Clinical Pratice of Pulmonary Function TestingDiagnosticObjective AssessmentMonitoringEvaluations for Disability / Impairment第5頁，共50頁。Lung volume and capacityVentilation functionDiffusion functionMechanics of breathingMain Programs of Pulmonary Function Testing第6頁，共50頁。Lung v

4、olumeLung volume means the maximal volume of gas contained by a lung.Lung volume = tidal volume(VT) + inspiratory reserve volume(IRV) + expiratory reserve volume(ERV) + residual volume(RV)Lung capacity: inspiratory capacity(IC), vital capacity(VC), functional residual capacity(FRV), total lung capac

5、ity(TLC)第7頁，共50頁。Curve of lung capacityIRVERVVTVCRVTLCICFRCVital capacity Themaximumvolumeofairthatcanbe inspiredbyforcefulexpiration.Residual volumeInspiratory reserve volumeExpiratory reserve capacityTotal lung capacity Tidal volumeFunctional reserve volume第8頁，共50頁。Tidal volume (VT)Thevolumeofairi

6、nspiredorexpiredwitheachnormalbreath.8-15ML/KG 第9頁，共50頁。Inspiratory capacity（IC）Inspiratory reserve volume（IRV）IC, themaximumvolumeofairthatcanbe inspiredbyforcefulexpiration. It is equal to VT plus IRV.IRV, themaximumextravolumeofairthatbe inspiredoverandabovethenormaltidalvolume.These reveal the m

7、aximam expansion of lung and chest at static state. 第10頁，共50頁。Expiratory reserve volume (ERV）Themaximumextravolumeofairthat beinspiredoverandabovethenormal tidalvolume.It reflects the power of expiratory muscle and abdominal muscle.第11頁，共50頁。Vital capacity （VC）Thelargestamountofairthatcanbeexpiredaf

8、teramaximalinspiratoryeffortfrequently.VC varies among normal bodies, so ratios of measured VC to predicted VC are used for judgment.Grading standard： ratio of measured VC to predicted VC 80%normal 60-79%mildly reduced 40-59%moderately reduced FRC%Pred 120% increased FRC10L hyperventilationMV3L hypo

9、ventilation 第20頁，共50頁。Alveolar ventilation (VA)The amount of air reaching the alveoli per minute at rest.Anatomic dead space: thespaceintheconducingzoneoftheairwaysoccupiedbygas thatdoesnotexchangewithbloodinthepulmonaryvessels, such as the space in nose and pharynx.Alveolar dead space: some of the

10、alveoli themselves are nonfunctional or only partially functional because of absent or poor blood flow through adjacent pulmonary capillaries.Physiological dead space（VD）= Anatomic dead space + Alveolar dead space . VA=（MVVD）RR第21頁，共50頁。VA varies in bodies and ranges from 3 to 5.5L. VA reflects the

11、effective ventilation. Reduction of MVV and increased dead space will result in alveolar hypo-ventilation.Dead space that results from deep and slow breathing is less than that of shallow and rapid breathing. So less respiratory rate and more VT will be better for VA.Alveolar ventilation (VA)第22頁，共5

12、0頁。Maximal volumtary ventilation （MVV）The total amount of new air moved into the respiratory passages by deepest and faster breathing in each minute. It depends on lung volume, compliance of lung and thorax, airway resistance and respiratory muscle. MVV%Pred 80% normal Damage grading： MVV%Pred 60-79

13、% mildly reduced 40-59% moderately reduced 40% severely reduced 第23頁，共50頁。 Increased airway resistance: asthma Thoracic deformity or neuromuscular diseases: kyphoscoliosis, Guillian-Barre syndrome Diseases of lung tissue：pulmonary edema Main causes of reduced MVV第24頁，共50頁。Timed Vital Capacity (TVC)F

14、VCFEV1FEV1 /FVC%MMEFPEF第25頁，共50頁。Timed Vital Capacity (TVC)FVC(forced vital capacity):This is the amount of air expelled from the lungs after first filling the lungs to maximum extent and then expiring rapidly and forcefully.FEV1(forced expiratory volume in one second)is the amount that can be got i

15、n the first second when FVC is measured.FEV1/FVC%：ratio of FEV1 to FVC第26頁，共50頁。Timed Vital Capacity (TVC)MMEF (maximal mid-expiratory)：After FVC divided into four average parts, divide the amount of the two middle parts by the corresponding expiratory time, MMEF will be got.第27頁，共50頁。 Timed Vital C

16、apacity (TVC) FVC%Pred 80% FEV1%Pred 80% FEV1/FVC 70%-80% FEV1%Pred can be used to evaluate the damage degree of ventilation and differentiate obstructive ventilation dysfunction from restrictive ventilation dysfunction.第28頁，共50頁。TimeVolume curvetime（s）0 1 2 3 4 5abcVolume (l)FEV1 FVCRVTLCSVC FVCnor

17、malrestrictiveobstructive第29頁，共50頁。 Clinical SignificanceIn normal body, FVC is closed to VC. Increased intrapleuralpressure makes small airway close in earlier stage of expiration. At this situation, FVC is less than VC. It happens to patients with COPD.Evaluate ventilation dysfunction： obstructive

18、 diseases: FEV1 /FVC% reduced, flat curve restrictive diseases:FEV1/FVC% normal or increased, gradient curve第30頁，共50頁。Grading Classification of Ventilation Function in COPD (bronchial dilator used)levelFEV1/FVCFEV%PredI70%80%II70%50%FEV%Pred 80%III70%30%FEV%Pred50%IV70%30% or50%,chronic respiratory

19、failure第31頁，共50頁。PEF (peak expiratory flow)The maximal flow during a forceful expiration. PEF should be measured in the morning, afternoon and before sleeping. PEFR= （PEFmaximum-PEFminimum) 2 PEFmaximum+PEFminimumPEF help to evaluate the chage of airway resistance. 100%第32頁，共50頁。Classification of ve

20、ntilation dysfunctionObstructive ventilation dysfunctionRestrictive ventilation dysfunctionMixed ventilation dysfunction第33頁，共50頁。Characteristics of ventilation dysfunctionobstructiverestrictivemixedLung capacityVCN or FRC unsureTLCN or unsureRV/TLCunsureunsure第34頁，共50頁。obstructiverestrictivemixedFE

21、V1 FEV1/FVC N orN orMVV MMEF Characteristics of ventilation dysfunction第35頁，共50頁。Diffusion functionGas exchange function means the course of gas exchange, including the exchange of O2 and CO2 between alveolus and blood, blood and histocyte. It involves lung ventilation, blood perfusion, ventilation-

22、perfusion ratio and diffusion function.Diffusion function can be measured to evaluate gas exchange function to some extent.第36頁，共50頁。Diffusion functionThe gas exchange between alveolus and blood capillary from the high partial pressure side to the low side.Relative factors: molecular weight, solubil

23、ity, gas partial pressure gradient, diffusion area, diffusion distance.第37頁，共50頁。Gas ExchangePO2104 mm HgPCO240 mm HgPO2104 mm HgPCO240 mm HgPO240 mm HgPCO245 mm Hg第38頁，共50頁。 Clinical significance Factors that can reduce the capacity of diffusion:Reduced effective diffusion area: atelectasis, airway

24、 obstruction, pulmonary embolism Increased diffusion distance: PIF, pulmonary edema, sarcoidosis, alveolar cell carcinomaThe capacity of diffusion also depends on gas partial pressure. 第39頁，共50頁。FlowVolume curve (F-V loop)Its a record about the course that take a rapid expiration to the extent of RV

25、 after a maximal inspiration to the extent of TLC. The flow rises rapidly at the beginning of forceful expiration and reaches the point of PEF soon. With the reduction of VC, the flow goes down perpendicularly almost. 第40頁，共50頁。第41頁，共50頁。 PEF and Vmax75 reflect the main airway resistance and respira

26、tory muscle strength. Vmax50 and Vmax25 reflect small airway resistance. Descending branch sinks to the volume axis in obstructive diseases, but VC may not reduce.In restrictive diseases, the curves rise sharply and the descending branches sink nearly perpendicularly. They have reduced VC.FlowVolume curve (F-V loop)第42頁，共50頁。flowvolumeTypes of FlowVolume curves of Different Ventilation DysfunctionRVTLC normalobstructiverestrictivemixed第43頁，共50頁。changeable External chest typedupper airway obstructionflowvolumeex