《心肺交互作用精选PPT.ppt》由会员分享，可在线阅读，更多相关《心肺交互作用精选PPT.ppt（66页珍藏版）》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、关于心肺交互作用关于心肺交互作用第1页，讲稿共66张，创作于星期日Basic physiology of heartlung interactionPump function:Preload at a given HRPra or CVPAfterload Contractility.Return function:Blood volume(vein)stressed and unstressedComplianceResistanceCO第2页，讲稿共66张，创作于星期日PreloadTransmural pressure跨壁压（Ptm）舱或血管内外压力差=血管内收缩压 Ppl非胸腔内血管外
2、压=大气压（传感器的零点）胸腔内血管被胸膜腔内压包围胸膜腔内压随通气周期变化Ppl RV前负荷自主呼吸或负压呼吸时Ppl 和血管内主动脉压力均下降Ppl下降幅度大于主动脉压力下降幅度Ptm实际增加LV后负荷、SV 第3页，讲稿共66张，创作于星期日Four mechanisms participate in the cyclic changes of SV observed during mechanical ventilation.First,during insufflation,venous return decreases due to an increase in pleural p
3、ressure.This decrease in RV preload leads to a decrease in RV output that subsequently leads to a decrease in left ventricular output.Second,RV afterload increases during inspiration because the increase in alveolar pressure is greater than the increase in pleural pressure.However,left ventricular p
4、reload in-creases during insufflation because blood is expelled from the capillaries toward the left atrium.Finally,left ventricular afterload decreases during inspiration because positive pleural pressure decreases the intracardiac systolic pressure and the transmural pressure of the intrathoracic
5、part of the aorta CCM.2009第4页，讲稿共66张，创作于星期日Ventricular afterloadDefinition:the force opposing ejectionVentricular afterload is represented by the level of transmural pressure,in the course of systole,within either the aortic root(LV afterload)or the pulmonary artery trunk(RV after-load)The transmura
6、l rather than the intraluminal pressure must be considered because these great vessels as well as the ventricles are exposed to an extramural pressure(i.e.,ITP)which is usually non atmospheric.The mechanisms whereby respiration interacts with LV and RV afterload are different.第5页，讲稿共66张，创作于星期日LV aft
7、erloadAt the onset of spontaneous inspiration,the intraluminal pressure in the aortic root decreases less than does ITP,due to the connection of this vessel with extrathoracic arteries.As a result,aortic transmural pressure increases.With spontaneous breathing therefore,LV afterload is greater in in
8、spiration than in expiration.A symmetrical chain of events leads to a reduced LV afterload in the course of a transient increase in ITP,such as with positive pressure inflation of the lungs.Steady increases in ITP,as effected with PEEP,similarly unload the LV with potentially beneficial consequences
9、 in presence of left heart failure,as described in greater detail below(Sect.Effects of PEEP on cardiac output in Part II).Conversely,patients with obstructive sleep apnea have bouts of greatly negative ITP which increase LV after-load,thus contributing to LV hypertrophy 第6页，讲稿共66张，创作于星期日RV afterloa
10、dA seminal paper by Permutt shows that RV afterload is highly dependent on and increases with the proportion of lung tissue in West zone 1 or 2,as opposed to zone 3 conditions.Zones 1 or 2 exist whenever the extraluminal pressure of alveolar capillaries(which is close to alveolar pressure,PA)exceeds
11、 the intraluminal value,leading to vessel compression.In zone 3 by contrast,intraluminal capillary pressure exceeds PAFor hydrostatic reasons,zones 1 and 2 are more likely to occur in nondependent parts of the lung.Furthermore,respiratory changes in the intraluminal pressure of alveolar capillaries
12、tend to track changes in ITP and thus to decrease more than does PA during a spontaneous inspiration and to increase less than does PA on inflation of the lung with positive pressure.Thus,any increase in lung volume,whether in the context of spontaneous or mechanically assisted breathing,has the pot
13、ential to promote the formation of zones 1 and 2 at the expense of zone 3,and thus to increase RV afterload.These considerations are of high clinical relevance,notably concerning the possible induction or aggravation of acute cor pulmonale by mechanical ventilation,as described below(Sect.Mechanical
14、 ven-tilation and acute cor pulmonale in Part II).Intensive Care Med(2009)35:4554第7页，讲稿共66张，创作于星期日Afterload：effect of lung inflation肺膨胀影响CO肺膨胀挤压肺泡内血管肺膨胀必须增加胸膜腔内压PvPA时影响很小第8页，讲稿共66张，创作于星期日Zones of the lungZone 1:PA Pa Pv Zone 2:Pa PA Pv Zone 3:Pa Pv PA The zones of the lung divide the lung into three
15、 vertical regions,based upon the relationship between the pressure in the alveoli(PA),in the arteries(Pa),and the veins(Pv):第9页，讲稿共66张，创作于星期日Zones of the lung肺动脉和静脉压力与肺部区域有关肺尖最低肺底最高直立位肺顶部Pa很可能低于PAWest J,Dollery C,Naimark A(1964).Distribution of blood flow in isolated lung;relation to vascular and al
16、veolar pressures.J Appl Physiol 19:71324.第10页，讲稿共66张，创作于星期日Zones of the lung 全肺PA=02 cmH2O直立位肺尖与肺底动脉压差=20 mmHg受重力影响全肺静脉压=5 mmHg肺尖部静脉压=-5 mmHg肺底部静脉压=+15 mmHg PAP=25/10 mmHg（Mean=15 mmHg）肺尖部mPAP=5 mmHg 肺底部mPAP=25 mmHg 第11页，讲稿共66张，创作于星期日Zones of the lung正常人群全部肺区Pa PAZone 1 正常情况下不存在正压通气时可以存在 PAPa受肺泡压力影响
17、区域血管彻底塌陷血流消失死腔通气第12页，讲稿共66张，创作于星期日Zones of the lungZone 2 Zone 2 位于心脏上方位于心脏上方 3cm 3cm以上肺区以上肺区 区域血流呈搏动状毛细血管床静脉端阻塞无血流动脉端压力超过PA时产生血流如此反复循环正常肺大部分位于正常肺大部分位于Zone 3Zone 3存在连续血流zone 1通气/血流比 zone 3第13页，讲稿共66张，创作于星期日Zones of the lungPA Pv(West zone II肺区)右室后负荷随肺膨胀增加随肺泡压1:1 增加肺血管血流淤滞肺水第14页，讲稿共66张，创作于星期日The rela
18、tion between lung volume and the pulmonary vascular resistanceAs lung volume increases from residual volume(RV)to total lung capacity(TLC),the alveolar vessels become increasingly compressed by the distending alveoli,and so their resistance increases,whereas the resistance of the extra-alveolar vess
19、els(which become less tortuous as lung volume increases)falls.The combined effect of increasing lung volume on the pulmonary vasculature produces the typical“U shaped”curve as shown,with its nadir,or optimum,at around normal functional residual capacity(FRC).Whittenberger JL,et al.J Appl Physiol 196
20、0;15:87882.第15页，讲稿共66张，创作于星期日FrankStarling relationships between ventricular preload and stroke volumeA given change in preload induces a larger change in stroke volume when the ventricle operates on the ascending portion of the relationship(A,condition of preload dependence)than when it operates on
21、 the flat portion of the curve(B,condition of preload independence).第16页，讲稿共66张，创作于星期日FrankStarling relationships between ventricular preload and stroke volumeSchematic representation of FrankStarling relationships between ventricular preload and stroke volume in a normal heart(A)and in a failing he
22、art(B).A given value of preload can be associated with preload dependence in a normal heart or with preload independence in a failing heart.第17页，讲稿共66张，创作于星期日Return functionHeartstressed volumeUnstressed volumeHeight:Total BVEmptying BVResistanceCompliance:Surface/HeightrelationshipReturn function:B
23、lood volume(veins/venules)stressed and unstressedComplianceResistance第18页，讲稿共66张，创作于星期日Return function正常静脉回心反流梯度=4 8 mmHgPpl 小量增加可显著改变静脉回心反流梯度Ppl 0时的两种代偿过程增加血容量补液一段时间后肾脏盐潴留代偿机制发挥作用静脉容量血管收缩Unstressed stressed volume stressed volume迅速增加 stressed volume 1015 ml/kg第19页，讲稿共66张，创作于星期日Return functionUnstre
24、ssed volumeStressed volumeStressed volumeUnstressed volumeContraction of smooth muscle in vascular wallsReturn to heart 第20页，讲稿共66张，创作于星期日the interaction of venous return curve(upper left)and cardiac function curve(upper right)define the working cardiac output,venous return and right atrial pressure
25、(Pra)valuesGuyton AC.Determination of cardiac output by equating venous return curves with cardiac response curves.Physiol Rev 1955;35:123 129.第21页，讲稿共66张，创作于星期日 For example患者：中度肺疾病，PEEP=20 cmH2O Ppl可能增加8 cm H2O（约7 mmHg）相对于大气压 CVP=15 mmHg 室壁膨胀压=8 mmHg第22页，讲稿共66张，创作于星期日For example心脏水平外周毛细血管压=15 mmHg
26、正常外周静脉回心阻力=4 8 mmHg 外周静脉静水压=19 23 mmHg净液体滤过到组织间隙背侧毛细血管额外静水压平均值=7 cm 该部位外周静脉静水压=2630mmHg高的心脏充盈压可能增加高PEEP患者CO代价：血管内血浆液体渗出增加第23页，讲稿共66张，创作于星期日Model of the circulation showing factors that influence systemic venous drainageRH 和胸腔内大静脉受Ppl影响，并随呼吸周期变化吸气时膈肌下降 IAP 呼气时IAP正常（接近大气压）外周静脉压不受呼吸周期影响全身性静脉回流(broken a
27、rrow)取决于驱动压（胸腔外大静脉EGV压-RAP）自主吸气时Ppl(RAP)，IAP(EGV)第24页，讲稿共66张，创作于星期日Effects of increase in airway pressure and volumeRight ventricleDecreased preloadIncreased afterloadReduced contractilityCompression of heart in cardiac fossaLeft ventricleDecreased preloadDecreased complianceVariable effects on(auto
28、nomous nervous system control of)contractilityDecreased afterloadCompression of heart in cardiac fossaMechanical ventilation alters intrathoracic pressures and thereby affects the cardiovascular system,mainly the right ventricle第25页，讲稿共66张，创作于星期日Cardiovascular effects of mechanical ventilation and a
29、pplication of PEEP第26页，讲稿共66张，创作于星期日Effects of increase in airway pressure and volume气道压力和容量对心脏负荷和功能的影响很复杂对CO的影响取决于心脏和肺血管的基础功能Paw 对前负荷的影响通常占优右室后负荷损害性增加难以预测血液动力学严重受损时应考虑缺乏液体反应时应考虑Echocardiography 可指导治疗 应考虑心肺交互作用对临床表现和治疗的影响第27页，讲稿共66张，创作于星期日Hemodynamic monitoringBlood pressureBP （随呼吸机设置变化）意味着 CO 、组织氧合
30、需要恢复先前通气设置呼吸正压 而BP没有下降并不意味着CO没有下降CO 时神经-体液反射能迅速增加SRV以维持或增加BPBP 检测CO变化特异性高，敏感性低第28页，讲稿共66张，创作于星期日Hemodynamic monitoringCVPCVP 不表示血容量CVP 不能表示容量反应性一个特定的CVP值不表明患者是否具有容量反应性高CVP表明患者不太可能具有容量反应性 CVP 10 12mmHg第29页，讲稿共66张，创作于星期日Hemodynamic monitoringCVP应用CVP时首先要基于临床和生化检查来判断患者是否需要优化血液动力学其次是快速补液是否改善血液动力学最后是当CVP
31、随扩容增加时是否能增加COCVP应在一定的安全范围内第30页，讲稿共66张，创作于星期日Hemodynamic monitoringCVP For example患者：中度肺疾病，PEEP=20 cmH2O Ppl可能增加8 cm H2O（约7 mmHg）相对于大气压 CVP=15 mmHg 室壁膨胀压=8 mmHg第31页，讲稿共66张，创作于星期日Hemodynamic monitoringCVP心脏水平外周毛细血管压=15 mmHg 外周静脉回心阻力=4 8 mmHg 外周静脉静水压=19 23 mmHg净液体滤过到组织间隙背侧毛细血管额外静水压平均值=7 cm 该部位外周静脉静水压=2
32、630mmHg高的心脏充盈压可能增加高PEEP患者CO代价：血管内血浆液体渗出增加第32页，讲稿共66张，创作于星期日存在较大肺分流时，低CO影响PaO2CO SvO2 CaO2 监测SvO2 or ScvO2有用SvO2 or ScvO2很低表明增加CO将增加PaO2第33页，讲稿共66张，创作于星期日Diagnostic uses of ventilatory variation in vascular pressure waves-Respiratory variations in central venous pressureInteraction of venous return a
33、nd cardiac function curves with respiratory variation第34页，讲稿共66张，创作于星期日Interaction of venous return and cardiac function curves with respiratory variations第35页，讲稿共66张，创作于星期日Evaluation of respiratory function CVP 与 PAOP 可用来评价通气功能PAOP 通气变异度可表明Ppl的变化27.自主负压吸气时，PAOP 下降轻度低估了Ppl的下降大多数病人肺充气时左室充盈增加正压呼吸时，PAO
34、P增加轻度高估了Ppl的增加第36页，讲稿共66张，创作于星期日Evaluation of respiratory functionCVP的变化基本不反应Ppl的变化右心容量来源于胸腔外基本不随Ppl而变化吸气触发时 CVP or PAOP出现大的负向变化 trigger 设置不当Raw 肺顺应性 吸气驱动增强需调整通气设置或增强镇静第37页，讲稿共66张，创作于星期日Evaluation of respiratory functionCVP随MV显著增加表明Ppl 显著增加胸壁顺应性 胸壁水肿胸腔积液量大IAP增加第38页，讲稿共66张，创作于星期日Evaluation of respira
35、tory function用力呼气使CVP增高需观察多个呼吸周期取呼气末获得值（最长和最低值）(Fig.3b)呼气阶段患者增加收缩呼气肌时，整个呼气阶段心脏充盈压增加(Fig.3c)这些患者CVP 呼气末值误导前负荷的估价取呼气开始时的CVP值可能更有效患者试图谈话时消失气管插管降低呼气肌收缩后消失第39页，讲稿共66张，创作于星期日Example of pulmonary artery occlusion pressure(Ppao),a reflection of left atrial pressure,and CVP in a patient on a pressure support
36、 of 6 cmH2O第40页，讲稿共66张，创作于星期日Conclusion对于简单的MV患者间断观察BP和SpO2足够了通气管理很困难时监测血液动力学试图增加PaO2时需评价CO以保证MV不降低DO2从CVP和BP波形可获得很多信息指导治疗第41页，讲稿共66张，创作于星期日Using heartlung interactions to assess fluid responsiveness during mechanical ventilation第42页，讲稿共66张，创作于星期日Respiratory variations in arterial pressure and strok
37、e volume控制通气吸气段Ppl 静脉回心梯度 RV充盈和CO BP肺充气 肺静脉排空 LV充盈增加LV CO Ppl LV后负荷 控制通气呼气段BPSV第43页，讲稿共66张，创作于星期日Respiratory changes in airway and arterial pressures in a mechanically ventilated patient The pulse pressure(systolic minus diastolic pressure)is maximal(PPmax)at the end of the inspiratory period and mi
38、nimal(PPmin)three heart beats later(ie during the expiratory period).SVRI=CI/(MAP-CVP)MAP=CI/SVRI+CVP第44页，讲稿共66张，创作于星期日Using heartlung interactions to assess fluid responsiveness during mechanical ventilationRelationship between the respiratory changes in pulse pressure before volume expansion(Basel
39、ine；PP)and the volume expansion-induced changes in cardiac index(y-axis)in 40 septic patients with acute circulatory failure.The higher PP is before volume expansion,the more marked the increase in cardiac index induced by volume expansion.Michard F.Am J Respir Crit Care Med 2000,162:134138第45页，讲稿共6
40、6张，创作于星期日Using heartlung interactions to assess fluid responsiveness during mechanical ventilationRelationship between the respiratory changes in pulse pressure on ZEEP(y-axis)and the PEEP-induced changes in cardiac index(x-axis)in 14 ventilated patients with acute lung injury.The higher PP is on ZE
41、EP,the more marked the decrease in cardiac index induced by PEEP.Michard F.Am J Respir Crit Care Med 1999,159:935939.第46页，讲稿共66张，创作于星期日第47页，讲稿共66张，创作于星期日Using heartlung interactions to assess fluid responsiveness during mechanical ventilation第48页，讲稿共66张，创作于星期日Using heartlung interactions to assess f
42、luid responsiveness during mechanical ventilation第49页，讲稿共66张，创作于星期日第50页，讲稿共66张，创作于星期日Using heartlung interactions to assess fluid responsiveness during mechanical ventilationMichard F.Am J Respair Crit Care Med 1999;159:935939.第51页，讲稿共66张，创作于星期日Determinants of pulse variation第52页，讲稿共66张，创作于星期日Ventil
43、atory variations in arterial pressure or stroke volume have also been shown not to be predictive in patients with smaller tidal volumes,increased West zone II conditions and in patients with pulmonary hypertension 24,25,26第53页，讲稿共66张，创作于星期日Hemodynamic changes during discontinuation of machanical ven
44、tilation in medical intensive care unit patients第54页，讲稿共66张，创作于星期日Hemodynamic changes during discontinuation of machanical ventilation in medical intensive care unit patients第55页，讲稿共66张，创作于星期日Hemodynamic changes during discontinuation of machanical ventilation in medical intensive care unit patients
45、第56页，讲稿共66张，创作于星期日Hemodynamic changes during discontinuation of machanical ventilation in medical intensive care unit patients第57页，讲稿共66张，创作于星期日Patterns of cardiac function and plasma catecholamine levels differed between patients who did or did not achieve spontaneous ventilation with a trial of co
46、ntinuous positive airway pressure.Cardiac function must be systematically considered before and during the return to spontaneous ventilation to optimize the likelihood of success.Susan KF.American Journal of Critical Care.2006;15:580-594第58页，讲稿共66张，创作于星期日summaryEffects of increase in airway pressure
47、 and volume on right and left ventricleHeart-lung interactions may play a role in the manifestations and treatment of a variety of disordersUsing heartlung interactions (PPV)can assess fluid responsiveness during mechanical ventilationCardiac function must be systematically considered before and dur
48、ing the return to spontaneous ventilation to optimize the likelihood of success第59页，讲稿共66张，创作于星期日谢谢第60页，讲稿共66张，创作于星期日Hypoxic pulmonary vasoconstriction in human lungsAnaesthesiology 1997,86:308-315第61页，讲稿共66张，创作于星期日Hypoxic pulmonary vasoconstriction in human lungs第62页，讲稿共66张，创作于星期日Model of the circu
49、lation showing factors that influence systemic venous drainageRH and intrathoracic great veins are subjected to pleural pressure(PPl),which varies throughout the respiratory cycle.IAP increases with inspiratory diaphragmatic descent,and normalises to atmospheric(Patmos)with expiration.Peripheral ven
50、ous pressure is unaffected by respiration and so remains at atmospheric pressure throughout the respiratory cycle.Systemic venous drainage(broken arrow)depends on a driving pressure gradient between extrathoracic great veins(EGV)and the right atrium,and so during spontaneous respiration is maximised