生理学双语ppt课件呼吸

*,respiration,第五章 呼吸生理,1,respiration第五章 呼吸生理1,2,2,1.外呼吸,肺通气,（外界空气与肺泡之间的气体交换过程）,肺换气,(,肺泡与肺毛细血管之间的气体交换过程,）,呼吸的三个基本环节,3,1.外呼吸 呼吸的三个基本环节3,气体在血液中的运输,3.,内（组织）呼吸,血液与组织、细胞之间的气体交换过程,4,气体在血液中的运输4,肺通气和肺换气,5,肺通气和肺换气5,The goals of respiration are to provide oxygen to the tissues and to remove carbon dioxide. To achieve these goals, respiration can be divided into four major functional events:,6,The goals of respiration are t,pulmonary ventilation,which means the inflow and outflow of air between the atmosphere and the lung alveoli;,(2),diffusion of oxygen and carbon dioxide between the alveoli and the blood;,7,pulmonary ventilation, which m,(3),transport of oxygen and carbon dioxide in the blood and body fluids,to and from the cells; and,(4),regulation of ventilation,and other facets of respiration. This chapter is a discussion of pulmonary ventilation.,8,(3) transport of oxygen and ca,第一节 肺通气,9,第一节 肺通气9,一、实现肺通气的结构特点及功能,鼻、咽、喉、 气管直到终末细支气管,上呼吸道,下呼吸道,10,一、实现肺通气的结构特点及功能鼻、咽、喉、 气管直到终末,11,11,12,12,13,13,二、肺通气原理,14,二、肺通气原理14,（一）,肺通气,的动力,直接动力,：肺泡与大气之间的压力差,原动力,: 呼吸运动,呼吸肌收缩、舒张所造成的胸,廓的扩大和缩小，称为呼吸运 动。,15,（一）肺通气的动力15,1,呼吸运动,（1）,吸气运动,：,膈肌,收缩时中部下移，增大了胸腔的上下径，肺容积随之增大，产生吸气。,平静呼吸时膈肌收缩造成的通气量,占总通气量的4/5。,16,1呼吸运动16,17,17,当,肋间外肌,收缩时，增大了胸,腔的,前后径和左右径,，肺容积,随之 增大, 产生吸气。,18,当肋间外肌收缩时，增大了胸18,19,19,20,20,（2）,呼气运动,：,平静呼气时，因,膈肌和肋间外,肌 舒张，,肺依靠本身的回缩力,量而回位，产生呼气。,21,（2）呼气运动：21,用力呼吸：,除上述肌肉外，有更多的吸气,肌与呼气肌 参与呼吸运动。,22,用力呼吸：22,用力呼吸,吸气（主动,） 膈肌和肋间外肌收缩， 胸锁乳突肌、斜角肌也收缩,呼气（主动,） 膈肌和肋间外肌舒张， 腹壁肌肉、肋间内肌收缩,平静呼吸,吸气（主动,） 膈肌和肋间外肌收缩,呼气（被动）,膈肌和肋间外肌舒张,23,用力呼吸吸气（主动） 膈肌和肋间外肌收缩， 胸锁乳突肌、斜,呼吸运动,腹式呼吸,胸式呼吸,膈肌舒缩引起的呼吸运动伴以腹壁的起伏，所以称为,腹式呼吸,（abdominal breathing）。,24,呼吸运动 腹式呼吸 胸式呼吸膈肌舒缩引起的呼吸运动伴以腹,由肋间肌舒缩使肋骨和胸骨运,动所产生的呼吸运动，称为,胸,式呼吸,。Thoracic breathing,25,由肋间肌舒缩使肋骨和胸骨运25,1.,Mechanics Of Pulmonary Ventilation,627.4-628.3,A. Muscles That Cause Lung Expansion and Contraction,629.2-630.2,26,1. Mechanics Of Pulmonary Vent,The lungs can be expanded and contracted in two ways:,by downward and upward movement of the diaphragm to lengthen or shorten the chest cavity and,by elevation and depression of the ribs to increase and decrease the antero-posterior diameter of the chest cavity.,27,The lungs can be expanded and,Normal quiet breathing is accomplished almost entirely by the first of the two methods, that is, by movement of the diaphragm. During inspiration, contraction of the diaphragm pulls the lower surfaces of the lungs downward.,28,Normal quiet breathing is acco,Then, during expiration, the diaphragm simply relaxes, and the,elastic recoil,of the lungs, chest wall, and abdominal structures compresses the lungs.,29,Then, during expiration, the d,During heavy breathing, however, extra force is achieved mainly by contraction of the,abdominal muscles,which pushes the abdominal contents upward against the bottom of the diaphragm.,30,During heavy breathing, howeve,The second method for expanding the lungs is to raise the rib cage. when the rib cage is elevated, making the antero-posterior thickness of the chest about 20 per cent greater during maximum inspiration than during expiration.,31,The second method for expandin,Therefore, all the muscles that elevate the chest cage are classified as muscles of inspiration, and the muscles that depress the chest cage are classified as muscles of expiration. The most important muscles that raise the rib cage are the,external intercostals,.,32,Therefore, all the muscles tha,The muscles that pull the rib cage downward during expiration are (1) the,abdominal recti,which have the powerful effect of pulling downward on the lower ribs at the same time that they and the other abdominal muscles compress the abdominal contents upward toward the diaphragm, and (2) the,internal intercostals.,33,The muscles that pull the rib,As the external intercostals they contract, they pull ribs forward, and this causes leverage on the ribs to raise them upward, thereby causing inspiration. The internal intercostals function exactly oppositely, functioning as expiratory muscles, because they angle between the ribs in the opposite direction and cause opposite leverage.,34,As the external intercostals t,2,肺内压,肺内压是指肺泡内的压力。,吸气初，肺内压低于大气压，空气进入肺泡。呼气初，肺内压高于大气压，肺内气体流出,。,吸气末和呼气末，肺内压和大气压相等。,35,2肺内压35,Alveolar pressure,is the pressure of the air inside the lung alveoli.,When the glottis,声门,is open and no air is flowing into or out of the lungs, the pressures in all parts of the respiratory tree, all the way to the alveoli, are equal to atmospheric pressure, which is considered to be the zero reference pressure in the airways that is, 0 centimeters water pressure.,36,Alveolar pressure is the press,To cause inward flow of air into the alveoli during inspiration, the pressure in the alveoli must fall to a value slightly below atmospheric pressure (below 0).,37,To cause inward flow of air i,During normal inspiration, alveolar pressure decreases to about -1 centimeter of water. This slight negative pressure is enough to pull 0.5 liter of air into the lungs in the 2 seconds required for normal quiet inspiration.,38,During normal inspiration, alv,During expiration, opposite changes occur: The alveolar pressure rises to about + 1 centimeter of water, and this forces the 0.5 liter of inspired air out of the lungs during the 2 to 3 seconds of expiration.,39,During expiration, opposite ch,3. 胸内压,胸膜腔内的压力称为,胸内压,。,40,3. 胸内压胸膜腔内的压力称为胸内压。40,41,41,胸膜腔内压比大气压低，为,负压,。,平静呼气末胸膜腔内压约为-5-,3mmHg， 吸气末约为-10-5mmHg。,42,胸膜腔内压比大气压低，为负压。42,胸内压=大气压-肺回缩力,43,胸内压=大气压-肺回缩力43,胸内压,=,肺内压-肺弹性回缩力,= 大气压 - 肺弹性回缩力,若以1个大气压为0， 则,胸膜腔内压= 肺弹性回缩力,44,胸内压= 肺内压-肺弹性回缩力44,45,45,Pleural pressure,is the pressure of the fluid in the narrow space between the lung pleura and the chest wall pleura.,46,Pleural pressure is the pressu,Pleural pressure,is normally a slightly negative pressure. The normal pleural pressure at the beginning,of,inspiration is about -5 centimeters of water, which is the amount of suction that is required to hold the lungs open to their resting level.,47,Pleural pressure is normally a,Then, during normal inspiration, the expansion of the chest cage pulls outward on the lungs with still greater force and creates a still more negative pressure to an average of about - 7.5 centimeters of water.,48,Then, during normal inspiratio,（二）肺通气的阻力,弹性阻力,（70%）,非弹性阻力（30%）,49,（二）肺通气的阻力弹性阻力（70%）非弹性阻力（30%）4,1、弹性阻力和顺应性,（1）,弹性阻力,弹性组织在外力作用下变形时，,有对抗变形和弹性回位的倾向，,为弹性阻力。,50,1、弹性阻力和顺应性（1）弹性阻力50,（2）,顺应性,(compliance),顺应性是指在外力作用下弹性组织的可扩张性。,容易扩张者，顺应性大，弹性阻力小；,反之则相反。,51,（2）顺应性(compliance)顺应性是指在外力作用下弹,可见顺应性（C）与弹性阻,力（R）成反变关系：,C = 1 / R,52,可见顺应性（C）与弹性阻52,顺应性用单位压力变化（P）,所引起的容积变化（V）来表,示,，单位是L/cmH,2,O，即,C=V/PL/cmH,2,O,。,53,顺应性用单位压力变化（P）53,Compliance in the respiratory system,631.2-633.1,describes the distensibility of the lungs and chest wall.,is inversely related to elastance, which depends on the amount of elastic tissue.,is the change in volume for a given change in pressure.,54,Compliance in the respiratory,肺的,弹性阻力,肺表面张力（2/3）,肺组织弹性（1/3）,(3) 肺的,弹性阻力,的来源,55, 肺的弹性阻力肺表面张力（2/3）肺组织弹性（1/3）(,肺组织的弹性,主要来肺组织的弹性纤维和胶原纤维。,56,肺组织的弹性主要来肺组织的弹性纤维和胶原纤维。56,Resistence to,pulmonary ventilation,633.2-634.4,Resistant forces of the lungs. These can be divided into two parts:,(1) the,elastic forces of the lung tissue,itself,57,Resistence to pulmonary ventil,The elastic forces of the lung tissue are determined mainly by the elastin and collagen fibers interwoven among the lung parenchyma.,(2) the,elastic forces caused by surface tension of the fluid that lines the inside walls of the alveoli,and other lung air spaces.,58,The elastic forces of the lung,Nature of Lung Elastic Recoil,The elastic recoil of the lung consists of two kinds of,forces,tissue forces and surface tension forces. The,elasticity of lung tissue is due principally to elastin,弹性蛋白,fibers,in alveolar walls and surrounding small airways.,59,Nature of Lung Elastic Recoil5,肺泡表面张力,肺泡内壁有一薄层液体，它与肺泡,内气体形成了液-气交界面，这里存,在减小液-气界面的力，使肺泡趋于,缩小，称为,肺泡表面张力。,60, 肺泡表面张力肺泡内壁有一薄层液体，它与肺泡60,肺泡表面活性物质,是由,肺泡,型细胞,分泌的一种复,杂的,脂蛋白,，主要成分为二棕榈,酰卵磷脂。其主要作用是,降低表,面张力,。,61, 肺泡表面活性物质是由肺泡型细胞分泌的一种复61,Laplace定律：P=2T/r p 肺泡内压,T 表面张力 r 肺泡半径,由于小肺泡表面活性物质的密度大，大肺泡表面活性物质分子的 稀疏，则大小肺泡内压力相等，大小肺泡的稳定性。,62,Laplace定律：P=2T/r p 肺泡内压62,肺泡表面活性物质的作用,降低表面张力,维持大小肺泡的容积相对稳定,调节肺泡的回缩力，有利呼吸,使肺泡表面相对干燥，避免肺水肿,63, 肺泡表面活性物质的作用降低表面张力维持大小肺泡的容,The surface tension accounts for about two thirds of the total elastic forces in the normal lungs.,The surface tension elastic forces of the lungs also increase tremendously when the substance called,surfactant,is,not,present in the alveolar fluid.,64,The surface tension accounts f,Surfactant is a s,urface active agent,which means that it greatly reduces the surface tension of the water. It is secreted by special surfactant-secreting epithelial cells that constitute about 10 per cent of the surface area of the alveoli. These cells are are called,type II alveolar epithelial cells.,65,Surfactant is a surface active,Surfactant is a complex mixture of several phospholipids, proteins, and ions. Surfactant,consists primarily of the phospholipid, (DPPC) which is responsible for reducing the surface tension.,66,Surfactant is a complex mixtur,Abnormalities of Lung Elastic Recoil,Lung elastic recoil is increased by reduced surfactant activity resulting from decreased synthesis or inactivation.,The best-known clinical disorder associated with decreased surfactant synthesis is the respiratory distress,syndrome of the newborn.,67,Abnormalities of Lung Elastic,Surfactant production may also be,impaired following the interruption of pulmonary perfusion, as in pulmonary thromboembolism,血栓栓塞,.,Hydrostatic pulmonary edema and adult respiratory distress syndrome are,associated with surfactant inactivation due to alveolar,flooding.,68,Surfactant production may also,The consequences of decreased surfactant activity include decreased lung compliance due to increased,surface tension and alveolar collapse (atelectasis,肺萎陷,), decreased lung volumes (TLC,total lung capacity,RV,residual volume, and FRC,functional residual capacity,), and increased,elastic work of breathing.,69,The consequences of decreased,The decreased lung compliance of interstitial or infiltrative,浸润性,的,lung diseases results from two mechanisms,decreased distensibility and lung shrinkage,70,The decreased lung compliance,Pathologically these diseases are characterized by alveolar,filling with inflammatory exudate,渗出物,and/or replacement of,alveoli by fibrosis, and this loss of alveolar units or lung,shrinkage decreases compliance (see above).,71,Pathologically these diseases,In addition, these disorders may alter the,connective tissue elements of the lung. resulting in increased lung elastic recoil. As a result, TLC, RV, and functional residual capacity are decreased, and the elastic work,of breathing is increased in these disorders.,72,In addition, these disorders m,2、非弹性阻力,包括:,惯性阻力,粘滞阻力,气道阻力,73,2、非弹性阻力73,惯性阻力,是气流在发动、变速、,换向时因气流和组织的惯性所产,生的。平静呼吸时，惯性阻力小，,可忽略不计。,74,惯性阻力是气流在发动、变速、74,粘滞阻力,来自呼吸时组织相,对位移所发生的磨擦。,75,粘滞阻力来自呼吸时组织相75,气道阻力,来自,气体分子间和气体,分子与气道之间的磨擦，是非弹,性阻力的,主要成分,，约占80%-,90%。,76,气道阻力来自气体分子间和气体76,R与1/r,4,成正比,影响r的因素：,1、气道管壁平滑肌的神经调节,2、化学因素的影响,77,R与1/r4成正比影响r的因素： 1、气道管壁平滑肌的神经调,（三）呼吸功,78,（三）呼吸功78,三、基本肺容积和肺容量,（一）,基本肺容积,（pulmonary volume),1,潮气量,每次呼吸时吸入,或,呼出的气量为潮气量（tidal volume）。,平静呼吸时，潮气量为500ml 。运,动时增大。,79,三、基本肺容积和肺容量（一）基本肺容积（pulmonary,2,补吸气量,平静吸气末，再尽力吸气所能吸,入的气量为补吸气量（inspiratory,reserve volume），正常为1500-,2000ml。,80,2补吸气量80,3,补呼气量,平静呼气末，再尽力呼气所能呼出,的气量为补呼气量（expiratory,reserve volume），正常为900-,1200ml。,81,3补呼气量81,4,余气量,最大呼气末尚存留于肺中不能再,呼出的气量为余气量（residual,volume）。正常为1000-1500ml。,82,4余气量82,（二）,肺容量,（pulmonary capacities）,是基本肺容积中两项或两项以上的,联合,气量。,1,深吸气量,从平静呼气末作最大吸气时所能吸入的气量为深吸气量，它是潮气量和补吸气量之和。,83,（二）肺容量（pulmonary capacities）8,2,功能余气量,平静呼气末尚存留于肺内的,气量为功能余气量。,是,余气量和补呼气量之和,。,84,2功能余气量84,3,肺活量,最大吸气后，从肺内所能呼出的最大气,量称作肺活（vital capacity），,是潮气量、,补吸气量和补呼气量之和,。正常成年男,性平均约为3500ml，女性为2500ml。,85,3肺活量85,86,86,4.,时间肺活量,先深吸气，然后以最快的速度呼出气体，同时分别测量第1、2、3s末呼出的气量，计算其所占肺活量的百分数（正常人各为83%、96%和99%肺活量。),87,4. 时间肺活量87,88,88,时间肺活量不仅反映肺活量容量的,大小，而且反映了呼吸所遇阻力的,变化，所以是,评价肺通气功能的较,好指标。,89,时间肺活量不仅反映肺活量容量的89,Pulmonary Volumes And Capacities,628.3-629.1,A. Pulmonary Volumes,1. The,tidal volume,is the volume of air inspired or expired with each normal breath; it amounts to about 500 milliliters.,90,Pulmonary Volumes And Capaciti,2. The,inspiratory reserve volume,is the,maximum extra volume of air that can be,inspired over and above the normal tidal,volume; it is usually equal to about 3000,milliliters.,91,2. The inspiratory reserve vol,3. The,expiratory reserve volume,is the maximum extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration; this normally amounts to about 1100 milliliters.,92,3. The expiratory reserve volu,4. The,residual volume,is the volume of air remaining in the lungs after the most forceful expiration. This volume averages about 1200 milliliters.,93,4. The residual volume is the,Pulmonary Capacities,In describing events in the pulmonary cycle, it is sometimes desirable to consider two or more of the volumes together. Such combinations are called,pulmonary capacities.,94,Pulmonary Capacities94,The,vital capacity,equals the,inspiratory reserve volume,plus the,tidal volume,plus the,expiratory reserve volume.,This is the maximum amount of air a person can expel from the lungs after first filling the lungs to their maximum extent and then expiring to the maximum extent (about 4600 milliliters).,95,The vital capacity equals the,The,total lung capacity,is the maximum,volume to which the lungs can be,expanded with the greatest possible effort,(about 5800 milliliters); it is equal to the,vital capacity,plus the,residual volume.,96,The total lung capacity is th,All pulmonary volumes and capacities are about 20 to,25,per cent less in women than in men,and they are greater in large and athletic people than in small and asthenic,无力的,people.,97,All pulmonary volumes and capa,To,perform a forced vital capacity (FVC) maneuver, the subject inhales to total lung capacity, exhales as forcefully and,rapidly as possible to residual volume, and then returns to,TLC by a rapid forceful inhalation.,98,To perform a forced vital capa,During forced inspiration, flow increases rapidly above residual volume because,the inspiratory muscles function most advantageously at,low lung volumes. As inspiration progresses, flow remains,high because airway resistance falls as lung volume increases. Near TLC flow decreases as the inspiratory muscles shorten, and inspiratory force,decreases.,99,During forced inspiration, flo,=12,18,500,=69L/min,四、,肺通气量,（一）每分通气量和每分最大通气量,每分通气量=呼吸频率,潮气量,100,=1218500四、肺通气量（一）每分通气量和每分最大通,The,minute respiratory volume,is the total amount of new air moved into the respiratory passages each minute; this is equal to the,tidal volume,times the,respiratory rate.,The normal tidal volume is about 500 milliliters, and the normal respiratory rate is about 12 breaths per minute. Therefore, the,minute respiratory volume averages about,6,L/min.,101,The minute respiratory volume,每分最大通气量,尽力作深快呼吸时，每分钟所能,吸入,或,呼出的最大气量为最大通,气量。,102,每分最大通气量102,（二）,无效腔（dead space)和肺泡通气量,生理无效腔,解剖无效腔,（150ml）,肺泡无效腔,103,（二）无效腔（dead space)和肺泡通气量生理无效腔,Dead space,636.5-6,a. Anatomic dead space,is the volume of the conducting airways.,is normally approximately 150 ml,104,Dead space104,Some of the air a person breathes never reaches the gas exchange areas but instead goes to fill respiratory passages where gas exchange does not occur, such as in the nose, pharynx, and trachea.,105,Some of the air a person breat,This air is called,dead space air,because it is not useful for the gas exchange process; the space in the respiratory passages where no gas exchange takes place is called the,dead space.,106,This air is called dead space,Normal Dead Space Volume. The normal dead space air in a young adult man is about 150 milliliters. This increases slightly with age.,107,Normal Dead Space Volume. The,The volume of all the space of the respiratory system besides the alveoli and their other closely related gas exchange areas; this space is called the,anatomic dead space.,108,The volume of all the space of,On occasion, some of the alveoli themselves are nonfunctional or are only partially functional because of absent or poor blood flow through adjacent pulmonary capillaries. Therefore, from a functional point of view, these alveoli must also be considered dead space.,109,On occasion, some of the alve,When the alveolar dead space is included in the total measurement of dead space, this is called,physiologic dead space,in contradistinction to the anatomic dead space.,110,When the alveolar dead space i,In a normal person, the anatomic and physiologic dead spaces are nearly equal because all alveoli are functional in the normal lung, but in a person with partially functional or nonfunctional alveoli in some parts of the lungs, sometimes the physiologic dead space is as much as 10 times the volume of the anatomic dead space, or 1 to 2 liters.,111,In a normal person, the anatom,Alveolar ventilation per minute is the total volume of new air entering the alveoli and adjacent gas exchange areas each minute. It is equal to the respiratory rate times the amount of new air that enters these areas with each breath.,112,Alveolar ventilation per minut,VA = Freq. (VT - V0),where VA is the,volume of alveolar ventilation per minute,Freq is the,frequency of respiration per minute,VT is the,tidal volume,and V0 is the,physiologic dead space volume.,113,VA = Freq. (VT - V0)113,Thus, with a normal tidal volume of 500 milliliters, a normal dead space of 150 milliliters, and a respiratory rate of 12 breaths per minute, alveolar ventilation equals 12 X (500 - 150), or 4200 ml/min.,114,Thus, with a normal tidal volu,Alveolar ventilation is one of the major factors determining the concentrations of oxygen and carbon dioxide in the alveoli,.,115,Alveolar ventilation is one of,每次吸入的气体，一部分留在从鼻至呼吸性细支气管之间的呼吸道内，这部分气体不参与肺泡与血液的气体交换,，故称为,解剖无效腔,，其容积约为150ml。,116,每次吸入的气体，一部分留在从鼻至呼吸性细支气管之间的呼吸道内,进入肺泡内的气体，也可因血流在,肺内分布不均而未能都与血液进行,气体交换，未能发生气体交换的这,一部分肺泡容量称为,肺泡无效腔,。,117,进入肺泡内的气体，也可因血流在117,150ml,350ml,500ml,118,150ml350ml500ml118,肺泡通气量,每分钟进入肺泡，能与血液进行气体交换的新鲜气体量。,肺泡通气量=,（潮气量-无效腔）,呼吸频率,119, 肺泡通气量每分钟进入肺泡，能与血液进行气体交换的新鲜气体,深慢,呼吸和,浅快,呼吸的效率比较,呼吸频率,（次/min）,潮气量,（ml ）,肺通气量,（ml/min）,肺泡通气量,（ml/min ）,12,6,24,500,1000,250,6000,6000,6000,4200,5100,2400,120,深慢呼吸和浅快呼吸的效率比较呼吸频率（次/min）潮气量（m,