呼吸系统呼吸生理respiratory physiology英五

1、Respiratory PhysiologyDr. Youmin Hu: 63846590-776542: jyOffice：Room 413, Building fourthObjectives of RespiratoryPhysiologySection1: Pulmonary Ventilation Section2: Respiratory GasesExchangeSection3: Oxygen and Carbon Dioxide Transport in BloodSection4: Regulation of Respiratory MovementSection1:Pul

2、monary VentilationVentilation: movement of airo and out ofgsI.Drive of Ventilation1. Respiratory Movement-the original driveof pulmonary ventilation(original drive)(Expiration)Expiratory muscles：(Inspiration)Inspiratory muscles:隔肌diaphragm、肋间外肌externalercostals肋间内肌 ernalercostals腹肌abdominisabdominal

3、 respiration vs thoracic respirationEupnea(平静呼吸） vs forced breathingBreathing rate is 10-20 breaths / minute at rest（Eupnea）, 40 - 45 atadults （ forced breathing）um exercise inInspiration uses external ercostals and diaphragmExpiration is passive at rest （Eupnea）, but usesernalercostals andabdominal

4、s during severe respiratory load（ forced breathing）2.rapulmonary Prere and Its ChangesDuring Respiration (direct drive)Eupnea:inspiration: -2 -1mmHgexpiration:1 2mmHgDeep breathing:inspiration: -100 -30mmHgexpiration:60 140mmHgArtifil RespirationCPR(cardiopulmonaryresusciion)s of Pulmonary Ventilati

5、on ：ProRespiratory muscle contraction& relaxation(original drive)Expan& recoil of the thoraxpleuralg expand & recoilrapulmonary prere changes(direct drive)Air moveso & out ofgs3.rapleural negative Pre(维持肺扩张状态的重要条件)rerapleural prereis the prere of thefluidbethe thin spacen thegpleura and the chestwal

6、l pleura.Its always negativepleuralprererapleural negative prereEnd quiet inspiration: -5 -10mmHgEnd quiet expiration: -3 -5mmHg The Formation ofrapleural negative Prerenatural volume of chest cagethe fluid in pleural space(两层胸膜间浆液的分子凝聚力)g volumerapleural pre= alveolar pre recoil force of= - 肺回缩力rer

7、e - g Physiologic Significance ofrapleuralnegative Prere Stretches (inflates) thegs Benefits to the return of venousblood and lymphp(气胸)othoraxII.Including:of Ventilation(弹性阻力)Elastic70%(非弹性阻力) 30%-elastic（R）顺应性）ElasticCompliance（C,C=1/RC=V/ P (L/cmH2O)distensibility (扩张性)1.gs ElasticRL =gs recoil f

8、orcome from：1.1gs Elasticthe elastic forof theg tie (1/3)surface tenof the fluidt lines the inside wallof the alveoli (2/3)Surface TenLaw of Laplace: Prere in alveoli isdirectly proportional tosurface ten; andAir Flowinversely proportional toradius of alveoli. Prere in smalleralveolus would be great

9、ern in larger alveolus, ifExpandCollapsesurface tensame in both.were thePulmonary Surfactant(肺表面活性物质,PS)Phospholiproduced by alveolar type II cells肺泡型细胞及呼吸性细支气管的Clara细胞和DPPC（dipalmitoylphosphatidylcholine，二棕榈酰卵磷脂）SP (surfactant-assoprotein)（SP-A、SP-B、SP-C、SP-D）PS: 脂类和蛋白混合物tedSurfactant prevents alve

10、olar collapse Physiology Importance of PSPS decreaserface tenwhich:increases pulmonary compliance , reduinspiratory Rredumatendency for alveoli to collapseains the dryness of the alveoli, preventsthe edema of the alveoli缺陷新生儿呼吸窘迫综合征（infant respiratory distress syndrome）或称透明膜病（hyaline membrane diseas

11、e）1.2gs Compliance( CL )Change ing volume per change intranspulmonary prere.100 x more distensibleCL (0.2L/cmH2O )n a balloon1）Specific Compliance (比顺应性, CL)the compliance per unit volumeCL = pulmonary compliance/residual volume2） Sic Compliance(静态顺应性)2. Thoracic elastic R. and Cchw.A：gcapacity=67%T

12、LC(totalgcapacity)向外， 吸气的动力向内，吸气的阻力无g elastic R： opes inspirationThoracic elastic R： aids or opes inspiration-elastic(非弹性阻力):Airwayis the80%-90%Airway of air(气道阻力 )to flowhe airways and is due to :ernal friction betn gas molecules friction betngas molecules and thewalls of the airways1.Distribution

13、of Airway正常时，主要来自大气道；但在疾病情况下，主要是小气道阻力增大，细支气管对气道阻力影响很大。AirwaycmH2O/(L/s)Airway locationNormal adultCOPD suffererPharynx (咽-喉部)0.60.6Diameter 2mm Airway0.60.9Diameter 2mm Airway0.33.5Total airway R1.55.02. Contributory Factors of Airwayair velocity(气流速度)air current forms (气流形式)mainly airway diameter(气

14、道管径)Airway Radius or diameter is KEY. radius by 1/2 by 16FOLD - think bronchodilator here!Poiseuilles Law3. Affecting Factors of Airway Diameter（1）跨壁压 Transpulmonary Prere肺实质对气道壁的外向放射状牵引Neural control of airway smooth muscleVagal efferentsAch,M receptor, constrictionSymapathetic efferentsNE,2 adrene

15、rgic receptor,relaxation-cholinergic)NANC nerves (-adrenergic,O bronchodiliInhibitory release VI（4）Local factorsionProstaglandins， histamineQ: 为何支气管哮喘等慢性阻塞性肺病患者呼气比吸气更为？III. Assessment of the PulmonaryVentilationSpirometer（肺量计）Pulmonary Volume(肺容积)Tidal volume，TV (潮气量) ，400-600 mlInspiratory reserve

16、volume, IRV (补吸气量), 1.5-2L 3）Expiratory reserve volume, ERV (补呼气量), 900-1200 ml 4）Residual volume, RV (残气量), 1-1.5L，远大于肺的自然容积（约500ml）。2. Pulmonary Capacity (肺容量)Inspiratory capacity, IC （深吸气量）=潮气量+补吸气量Functional residual capacity，FRC (功能残气量) , 2300mlVital capacity，VC (肺活量),3.5(M)/2.5 L(F)4) Totalg c

17、apacity, TLC (肺总量) ,5(M)/3.5L(F)Dynamicg VolumeFVC-forced vital capacity (用力肺活量or时间肺活量)FEV-forced expiratory volumn (用力呼气量)意义：反映肺通气阻力的变化，FEV1/FVC80%评价肺通能的较好指标。化)COPD ,asthmaFibrosis(3. Minute and Alveolar VentilationPulmonary ventilation=tidal volumebreathing rate, 6-9 Ltary ventilation(最大随意通气量)al v

18、oup to 150L/min通气贮量百分比Alveolar ventilation=(tidal volume-dead space)rateanatomical dead spacealveolar dead spacePhysiologicaldead spaceMinute and Alveolar VentilationMinute ventilation: Total amount of air moved o and out of respiratory system per minuteRespiratory rate or frequency: Number of breaths taken per minuteAnatomic dead space: Part of respiratory system where gas exchange does not take placeAlveolar ventilation: How much air per minute enters the parts of the respir