1、内源性呼气末正压 auto-PEEP,病例1: 摘要,男性，93岁，病历号127782 基础病 COPD 甲状腺功能低减 慢性肾功能不全 骨髓增殖性疾病 全身动脉粥样硬化症 冠心病，慢性心功能不全 肺部感染，呼吸功能衰竭 2008年10月25日转入ICU 呼吸机相关性肺炎,病例1: 摘要,生命体征,化验检查,HR 110 bpm MAP 70 mmHg RR 21 bpm Temp 37C,WCC 20.47 x 109/L K 4.2 mmol/L Na 138 mmol/L Cr 238 mol/L BUN 19.68 mmol/L Alb 26 g/L Bil 5.6 mol/L Glu
2、 11.3 mmol/L,病例1: 摘要,ABG,其他,FiO2 0.6 pH 7.398 PaCO2 61.7 mmHg PaO2 163 mmHg HCO3 37.3 mmol/L BE 12 mmol/L SaO2 99.9%,APACHE II 21 预期病死率35.6%,病例1: 摘要,呼吸机设置,一般情况,PRVC Vt 500 mL Tinsp 0.8 sec f 12 bpm PEEP 12 cmH2O FiO2 0.4,BP 156/64 mmHg NP 40 g/min UO 90 200 mL/hr Lasix 10 mg/hr iv PIP 29 cmH2O,病例1:
3、摘要,ABG,治疗措施,pH 7.422 PaCO2 59.2 mmHg PaO2 58.9 mmHg SaO2 91.9% HCO3 37.9 mmol/L BE 11.9 mmol/L LA 2.2 mmol/L,考虑 低氧血症 CO2潴留 乳酸轻度升高? 调整呼吸机参数 f 12 20 bpm FiO2 0.4 0.6,病例1: 摘要,病例1: 摘要,目前情况,主要问题,血压进行性降低 使用降压药物停用 呼吸持续性恶化 气道压力持续升高 组织灌注趋于恶化 UO 35 mL/hr,病例1: 摘要,可能原因,解决方法,肺炎引起感染性休克 误吸 气胸 心功能衰竭,检查 CXR PAC或PiCC
4、O 治疗 扩容升压药物 限液强心药物 肺复张 调整抗生素,病例1: 摘要,采取措施,病情变化,0700 调整呼吸机参数 f 20 12 bpm0715 调整呼吸机参数 FiO2 0.6 0.5,0705 BP 160/60 mmHg 0715 SpO2 100%, f 12 bpm, PIP 32 cmH2O 0750 SpO2 98%, HR 121 bpm, BP 169/99 mmHg 0900 UO 150 mL/hr,病例1: 摘要,病例1: 摘要,病情逐渐稳定3天后转入普通病房,总结,COPD患者应用机械通气需要较长的呼气时间 非常容易因气体陷闭造成auto-PEEP,内源性PEE
5、P (auto-PEEP),什么是auto-PEEP?正常情况下，呼气末肺容积(EELV)等于功能残气量(FRC) 呼气末肺容积(EELV)超过功能残气量(FRC)时，即存在PEEPi,内源性PEEP (auto-PEEP),为何发生动态过度充盈(dynamic hyperinflation)?动态气道塌陷导致气流受阻 呼气时间过短(RR过快或Vt过大) 呼气肌肉活动 增加呼气阻力的病变,导致动态过度充盈(DPH)的原因,气流阻力增加(呼气流速受限) 机械通气及急性呼吸功能衰竭患者DPH的主要机制呼气时间过短 IRV及自主浅快呼吸时的重要机制吸气后吸气肌肉活动增强,动态过度充盈, 气体陷闭和a
6、uto-PEEP,insp,exp,Time,Tidal volume,Trapped gas,Lung Volume,FRC,Obstructed Lungs,Normal Stiff Lungs,DPH及auto-PEEP对COPD患者的影响,呼吸系统 降低呼吸肌肉的效率 无效触发 增加呼吸功及呼吸肌肉乏力 增加胸腔内压及气压伤危险 心血管系统 减少静脉回流 降低左心室和右心室前负荷 增加右心室后负荷 降低左心室顺应性 生理指标测定结果 低估气道阻力 高估顺应性,DPH及auto-PEEP对COPD患者的影响,如何判断存在auto-PEEP,Rossi A, Polese G, Brand
7、i G, et al. Intrinsic positive end-expiratory pressure (PEEPi). Intensive Care Med 1995; 21: 522-536,如何判断存在auto-PEEP,特别关注：气道阻塞疾病和分钟通气量大 临床表现：吸气性呼吸困难胸围增大难以用循环系统疾病解释的心血管功能恶化,如何判断存在auto-PEEP,呼吸力学监测 PawFLOWResistanceVolumeCompliance PEEP压力控制通气时潮气量下降容量控制通气时气道压力升高不能用呼吸系统顺应性下降解释的平台压升高存在无效触发,控制通气,辅助通气和自主呼吸,
8、呼气阻断法 呼气末暂停持续6 sec 平均静态auto-PEEP 阻断器技术 记录气道压力和流速 产生流速时气道压力改变 最低动态auto-PEEP,食道气囊,如何测定auto-PEEP,如何测定auto-PEEP: 呼气末阻断,Flow (l/s),Volume (l),Pao (cmH2O),occlusion,PEEPi = 9.1,如何测定气体陷闭容积,内源性PEEP与Vtrap Draeger Evita XL延长呼气(extended exhalation) Taema Horus功能残气量(FRC) GE Engstrom Carestation,如何消除DPH的影响,Time,
9、Tidal volume,Trapped gas,Lung Volume,FRC,Tidal vol.,Tidal hyper-inflation,Apnea,Tidal Ventilation,减少DPH,How? 降低分钟通气量降低Vt (6-8 cc/kg) 减慢RR (8-10 b/min) 尽可能延长呼气时间,ABG,考虑思路,pH 7.422 PaCO2 59.2 mmHg PaO2 58.9 mmHg SaO2 91.9% HCO3 37.9 mmol/L BE 11.9 mmol/L LA 2.2 mmol/L,是否需要处理? 平时PaCO2如何? 既往结果的提示 如果没有既往
10、结果,病例1: 讨论,ABG,考虑思路,FiO2 0.6 pH 7.398 PaCO2 61.7 mmHg PaO2 163 mmHg HCO3 37.3 mmol/L BE 12 mmol/L SaO2 99.9%,如何根据急性发作时ABG确定平时的PaCO2?pH PaCO2/HCO3,病例1: 讨论,总结,合并循环功能衰竭的严重支气管痉挛 如果液体治疗无效 应当将auto-PEEP作为鉴别的可逆因素之一短暂的窒息试验(15 30 sec) 有助于鉴别,病例2: 摘要,42岁女性 个人史：吸烟病史 既往史： 弥漫性肺气肿 静脉使用利他林(ritalin) 现病史：急性气管炎合并呼吸功能衰竭
11、入院 入院后气管插管,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,入院时CXR 双肺底肺气肿 多部位
12、条状不张 没有肺炎或气胸表现 符合“利他林”肺表现,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,入院情况,初始治疗,
13、体温正常 轻度心动过速 HR 110 bpm BP 150/90 mmHg,支气管扩张药物 甲基强的松龙 抗生素,病例2: 摘要,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J
14、 Radiol 2000; 174: 1339-1340,34,Start breath,O2 breaths,Exp. hold,Insp. hold,Main screen,Menu,Quick start,Alarm profile,Save,Trends,i,!,12-25 15:32,Mode Volume Control,Automode,Admit patient,Nebulizer,Status,Additional values,Set ventilation mode,Pressure support ,PS above PEEP 10,PEEP 5,O2 conc. 30
15、,T. Insp. rise 5,Insp. cycle off 5,Trigger sensitivity V,Basic,I:E,Trigger,.,Cancel,Accept,.,35,Start breath,O2 breaths,Exp. hold,Insp. hold,Main screen,Menu,Quick start,Alarm profile,Save,Trends,i,!,12-25 15:32,Mode Volume Control,Automode,Admit patient,Nebulizer,Status,Additional values,.,呼吸频率14 2
16、2 bpm相适应? 平均潮气量350 ml 分钟通气量5 8 lpm auto-PEEP 6 cmH2O,30,监测结果,15,40,Pmean,8,PEEP,O2 (%),35,7.1,8.5,VTi,351,VTe,343,5,20,25,Additional settings,Ppeak (cmH2O),RR (b/min),MVe (l/min),病例2: 摘要,因乏力及营养不良难以脱离呼吸机 病情稳定一周后 镇静过度导致频繁窒息报警 更换呼吸机模式为SIMV + PSV,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular inst
17、ability caused by inadvertent positive end-expiratory pressure in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,37,Start breath,O2 breaths,Exp. hold,Insp. hold,Main screen,Menu,Quick start,Alarm profile,Sa
18、ve,Trends,i,!,12-25 15:32,Mode Volume Control,Automode,Admit patient,Nebulizer,Status,Additional values,Set ventilation mode,Pressure support ,PS above PEEP 10,PEEP 5,O2 conc. 30,T. Insp. rise 5,Insp. cycle off 5,Trigger sensitivity V,Basic,I:E,Trigger,.,Cancel,Accept,.,呼吸机设置,监测指标,SIMV+PSV SIMV (VC)
19、 f 12 bpm Vt 450 ml PSV PS 10 cmH2O PEEP 5 cmH2O,呼吸频率12 20 bpm 分钟通气量9 lpm 氧合满意 auto-PEEP 15 cmH2O PIP 44 cmH2O Pplat 26 cmH2O,病例2: 摘要,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in a patient with panlobular emphysema receivi
20、ng mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,病情恶化 心动过速 低血压(BP 60/40 mmHg) 意识不清随后 血压波动(SBP 60 155 mmHg) 脉搏90 160 bpm,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in
21、a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,心脏明显减小 双肺底气体闭陷 左侧更明显 左侧膈肌显露,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in
22、a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,治疗措施 快速补液 小剂量多巴胺 尿量满意,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressure in a pati
23、ent with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,呼吸机恢复初始设置 PSV模式 潮气量下降至325 ml 分钟通气量6 lpm 病情逐渐稳定,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory
24、 pressure in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例2: 摘要,双侧膈肌，肺底以及心脏大小恢复到初始状态,Deliganis AV, Steinberg KP, Stern EJ. Cardiovascular instability caused by inadvertent positive end-expiratory pressu
25、re in a patient with panlobular emphysema receiving mechanical ventilation: radiographic-physiologic correlation. Am J Radiol 2000; 174: 1339-1340,病例3: 摘要,64岁男性 因AECOPD导致呼吸性酸中毒收住ICU 吸烟史120 pack-year 既往史：肺功能检查提示严重阻塞性通气功能障碍(FEV1 34%),Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an
26、“occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,病例3: 摘要,治疗措施 支气管解痉药物吸入治疗 静脉茶碱 甲基强的松龙 抗生素 24小时后ABG：7.44/45/55 转入普通病房,Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,病例3: 摘要,2天后再次出现急性支
27、气管痉挛及呼吸窘迫 ABG: 7.19/69/60 气管插管+手法通气 血压下降(SBP 60 mmHg) 大量输液 多巴胺,Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,病例3: 摘要,ABG: 7.31/41/60 窦性心律，电机械分离(EMD) 开始心肺复苏 排除可逆因素 肺动脉栓塞 张力性气胸 心包填塞 低血容量,Rogers PL, Schlichti
28、g R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,病例3: 摘要,复苏持续20分钟后停止 始终未恢复脉搏 复苏终止后15分钟 自主呼吸出现 窦性心律 SBP 60 mmHg 转入ICU后1小时因顽固性低血压死亡,Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromecha
29、nical dissociation? Chest 1991; 99: 492493,病例3: 摘要,尸检结果 双侧肺大泡，肺气肿 右侧吸入性肺炎 气管插管位于隆突上方 无心包积液、肺动脉栓塞或气胸表现 无心肌梗塞表现,Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,总结,Rogers PL, Schlichtig R, Miro A, Pinsky M. Auto-PEEP during CPR: an “occult” cause of electromechanical dissociation? Chest 1991; 99: 492493,认识到COPD患者在气管插管及机械通气后可能出现因过度充盈导致的低血压 并进行相应的准备 对于这类患者的治疗非常关键,
