肺水测定及临床应用ppt课件

,肺水测定及临床应用,浙江大学医学院附属邵逸夫医院危重医学科,潘孔寒,Preface,Pubmed Extravascular Lung Water 1295篇，1968年2006年6月,内容,血管外肺水（EVLW）定义 EVLW的测定方法及原理 EVLW监测的意义及临床应用,血管外肺水（EVLW）定义,Extravascular Lung Water， EVLW 正常37 ml/kg 7 ml/kg或10 ml/kg, 提示EVLW升高 绝对值意义值的变化的意义 The hallmark of sepsis is increased capillary permeability, which manifests in the lungs as altered alveolarcapillary barrier function and is characterized by accumulation of extravascular lung water (EVLW). Sepsis特征: 毛细血管渗漏。肺内表现：肺泡毛细血管屏障功能改变及EVLW积聚,EVLW测定方法及原理,影像学法 比重法 双指示剂稀释法 单指示剂热稀释法 生物阻抗法,影像学法,胸片 Chest x-ray score Pistolesi M, Giuntini C. Assessment of extravascular lung water. Radiol Clin North Am 1978;16:551574. CT MRI,影像学法,超声 Transthoracic chest sonography A 4-step score of ultrasound Comet tail sign Semiquantitative The sensitivity and specificity of ultrasound was 97%, with a positive and negative predictive value of 94% and 98%, respectively. The correlation between ultrasound and radiologic score was significant (0.90). Jambrik Z, et al. Usefulness of ultrasound lung comets as a nonradiologic sign of extravascular lung water. Am J Cardiol 2004;93:12651270. Lichtenstein D, et al. The comet-tail artifact. An ultrasound sign of alveolar-interstitial syndrome. Am J Respir Crit Care Med 1997;156: 16401646. Soldati G. Lung sonography artifact movement or echotexture. Italian J Ultrasound 2001;4: 329338.,比重法,常应用于动物实验中 根据下列公式计算可得出EVLW 匀浆血红蛋白浓度=上清液血红蛋白浓度(匀浆含水百分比上清液含水百分比) 血重=匀浆重匀浆中血红蛋白浓度血液血红蛋白浓度 血液中水重=血重血液含水百分比 肺脏中总的水含量(TPW)=匀浆含水百分比匀浆重-附加水(蒸馏水) EVLW=TPW-血液中水重,比重法,方法经典，结果可靠 但多应用于动物实验，且不能动态观察EVLW变化，应用范围局限。,双指示剂稀释法(Double-indicator dilution method),基本装置及操作 通过颈内静脉或锁骨下静脉放置中心静脉(CV）导管，外接温度探头。 自中心静脉注射两种不同的指示剂，一种为热稀释指示剂，可渗透到毛细血管外，常用5GS或NS；另一种为染料稀释指示剂，只能保留在血管内，常用与白蛋白结合的吲哚绿（Indocyanine green, ICG, an intravascular tracer） 股动脉放置一根尖端带有热敏电阻丝的导管检测热稀释曲线，从股动脉导管中抽取股动脉血，分析得出染料稀释曲线。根据各自的稀释曲线分别得出稀释曲线的平均传送时间 (MTt)。根据史德华-汉密尔顿法(Stewart-Hamitonequation)，通过热稀释曲线计算出心输出量(CO)。,双指示剂稀释法基本原理,染料稀释指示剂不能渗透至毛细血管外，因此其所流经的所有容积量为GEDV(全心舒张末期容积)和PBV(肺内血容积)的总和，即ITBV(胸腔内血容积) 热稀释指示剂能渗透至毛细血管外，因此其所流经的所有容积量为EVLW和ITBV的总和，即 ITTV(胸腔内热容量),双指示剂稀释法,根据公式(1)：CO X MTt=指示剂所流经的所有容积量，可得 ITTV=CO X MTt (热稀释指示剂) ITBV = CO X MTt (染料稀释指示剂) 两者之间的差值为EVLW，即EVLW=ITTV-ITBV,双指示剂稀释法,检测染料指示剂的MTt准确性不够 操作复杂 费用昂贵 近年来该法已为先进的单指示剂热稀释法所替代。,单指示剂热稀释法,基本装置及操作 与双指示剂肺水测定法基本相同 放置中心静脉导管用以注射热稀释指示剂，股动脉放置一根尖端带有热敏电阻丝的导管，检测热稀释曲线。连接显示屏后注射热指示剂观察其热稀释曲线。,单指示剂热稀释法基本原理,心脏和肺可看成是由一系列序贯而独立的容积腔组成，股动脉导管检测到稀释曲线可看成是每个容积腔稀释曲线的组合，稀释曲线中最长衰变曲线对应的是其中的容积腔。将热稀释曲线取对数后进行标记，可得到稀释曲线的指数下斜时间 (DSt)。,单指示剂热稀释法基本原理,CO DSt(热稀释指示剂)=PBV+EVLW CO MTt(热稀释指示剂)=ITTV 可得 CO (MTtDSt)(热稀释指示剂)=ITTV(PBV+EVLW)=GEDV ITBV和GEDV之差值为PBV(肺血容量),两者之间有着较好的相关性，通过分析可计算出ITBV*。 根据ITTV=ITBV+EVLW 得出EVLW*=ITTV-ITBV*,可靠性,Sakka等将57例患者的GEDV(单指示剂热稀释法测得)和ITBV(双指示剂稀释法测得)进行分析得出方程：ITBV=125 X GEDV-28.4ml 进一步运用该方程计算出209例患者的ITBV*和EVLW*，并将其与由双指示剂稀释法则得ITBV和EVLW进行比较，得出 ITBV*=106 X ITBV1243ml， 其回归系数r=098(P00001) EVLW*：083XEVLW+1339ml， 其回归系数r=096(P00001)。 由此可见，单指示剂热稀释法测定ITBV和EVLW结果准确可靠。,脉波指示剂连续心排血量(Pulse Indicator Continous Cardiac Output, PiCCO)原理,PiCCO采用相继的三次的热稀释心排血量的平均值来获得一个常数，以后只需连续测定主动脉压力波形下收缩面积，分析与CO存在的关系,从而获得病人的连续心排血量（CCO）。还可以测量心脏的前负荷容量和血管外肺水量。,PiCCO,与传统热稀释导管不同的是，PiCCO从中心静脉导管注射室温水或冰水，在大动脉（通常是主动脉）内测量温度-时间变化曲线， 能够测量全心的相关参数，而不是仅仅以右心来代表全心 由于同时测量动脉压和CO，因此能够连续反映血管阻力（SVR）的变化 此外，根据温度稀释会受肺间质液体量（即血管外肺水）的影响，而染料稀释则不受其影响的特点（只受血管内、不受血管外因素的影响）。 早期PiCCO采用双指示剂法（温度和染料）测量全心舒张末容积、血管外肺水等一系列参数，并在大量临床数据的支持下总结了经验公式，发展成为现在只需用温度进行测量就可得到这些参数的单指示剂法。,测量参数,* 单次心输出量（CO）及每次心脏搏动的心输出量（PCCO） * 动脉压（AP） * 全身循环阻力（SVR） * 全心舒张末期容积（GEDV, normal range 680800mL/m2） * 血管外肺水（EVLW, normal range 37 mL/kg） * 胸内血容积（ITBV, normal range 8501000mL/m2） * 不间断容量反应（SVV，PPV） * 全心射血分数（GEF） * 心功能指数（CFI） * 肺血管通透性指数（PVPI),生物阻抗法,Transthoracic bioelectrical impedance analysis (BIA) An alternating electric current is passed through biologic tissue and the resistance to that current measured. This resistance is inversely proportional to the amount of water contained by the tissues within the electric field.,EVLW的意义及临床应用,防止和治疗肺水肿 预后指标 容量管理,肺水肿,高通透性肺水肿(如急性呼吸窘迫综合征) 高静水压性肺水肿(如心源性肺水肿)，,CVP/PAWP不能反映肺水肿,对16例感染性休克导致肺水肿的患者研究发现: EVLWI(血管外肺水含量指数变化)与 ITBVI(胸腔内血容量指数变化)有着较好的相关性(r=06) 而与CVP和PAWP的变化无明显相关 Intensive Care Med. 2002 Jun;28(6):712-8.,Significant negative correlation was found between EVLWi and PaO2/FiO2 (r = -0.53, CI -0.63 to -0.40, P 0.01) Critical Care 2005, 9(Suppl 1):P88,EVLW与Sepsis、肺损伤,A prospective cohort study in the Medical ICU at Grady Memorial Hospital (Atlanta, Georgia, USA) between July 2001 and March 2002 A total of 29 consecutive patients with severe sepsis from a medical intensive care unit in an urban university teaching hospital. A PICCO system Greg S Martin,et al. Extravascular lung water in patients with severe sepsis: a prospective cohort study. Critical Care 2005, 9:R74-R82,EVLW与Sepsis、肺损伤,Results Twenty-five of the 29 patients (86%) were mechanically ventilated, 15 of the 29 patients (52%) developed ARDS, and overall 28-day mortality was 41%. Eight out of 14 patients (57%) with non-ARDS severe sepsis had high EVLW with significantly greater hypoxemia than did those patient with low EVLW (mean arterial oxygen tension/fractional inspired oxygen ratio 230.7 36.1 mmHg versus 341.2 92.8 mmHg; P 0.001). Four out of 15 patients with severe sepsis with ARDS maintained a low EVLW and had better 28-day survival than did ARDS patients with high EVLW (100% versus 36%; P = 0.03). ARDS patients with a history of chronic alcohol abuse had greater EVLW than did nonalcoholic patients (19.9 ml/kg versus 8.7 ml/kg; P 0.0001). The arterial oxygen tension/fractional inspired oxygen ratio, lung injury score, and chest radiograph scores correlated with EVLW (r2 = 0.27, r2 = 0.18, and r2 = 0.28, respectively; all P 0.0001).,EVLW与Sepsis、肺损伤,Conclusions More than half of the patients with severe sepsis but without ARDS had increased EVLW,possibly representing subclinical lung injury.与亚临床肺损伤有关 EVLW correlated moderately with the severity of lung injury but did not account for all respiratory derangements.与肺损伤程度有关 EVLW may improve both risk stratification and management of patients with severe sepsis.监测EVLW 有助于危险度分层（可能为一预后指标）及重度sepsis的管理,早期应用PEEP有效降低肺水,Manuel等对18只高通透性肺水肿猪模型 研究发现，早期应用PEEP可以明显减少EVLW，同时获得较高的氧合指数(Pa02Fi02) Colmenen等对21只高通透性肺水肿猪模型进行研究 也发现类似的结果，进一步提示EVLW可能是影响氧合指数的重要因素。,表1 不同PEEP 水平对ARDS 绵羊EVLW的影响(.x s) Tab 1 Effect of PEEP on EVLW in sheep with ARDS( .x s) 组 别 时间点 n EVLWPmlkg- 1 ITBVPml GEDVPml 5 cm H2O 组 0 h 7 15. 6 3. 2 1031. 8 425. 1 831. 9 343. 1 1 h 7 14. 8 3. 5 1043. 9 365. 0 841. 8 293. 8 2 h 7 14. 7 3. 2 974. 1 355. 6 786. 0 286. 7 10 cm H2O 组 0 h 8 16. 5 4. 7 963. 1 254. 2 798. 4 189. 3 1 h 8 16. 6 5. 0 843. 3 237. 4 677. 3 171. 5 2 h 8 14. 7 4. 5 * 803. 6 205. 1 648. 2 165. 1 15 cm H2O 组 0 h 6 18. 4 6. 0 1034. 8 466. 3 838. 0 380. 0 1 h 6 15. 7 2. 6* 911. 4 335. 5 741. 5 265. 1 2 h 6 15. 3 3. 7* 969. 3 401. 8 781. 7 323. 7 * 与组内应用PEEP 前比较, P 0. 05 东南大学学报(医学版) 2004 年7 月,23 (4) 1995-2005 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.,肺水含量是ARDS的预后指标,Mortality as a function of EVLW. Patients were classified into four groups according to their highest EVLW value. The asterisk indicates statistical significance to the next higher EVLW group (2 test).,肺水含量是ARDS的预后指标,Sensitivity and specificity of ICU admission values for EVLW, SAPS II, APACHE II score, and SOFA score with respect to outcome according to ROC in 211 patients. The AUCs were 0.692 for APACHE II score, 0.766 for SAPS II, 0.756 for SOFA score, and 0.639 for EVLW, respectively. The comparison between AUCs for EVLW with SOFA score (p = 0.012) and SAPS II (p = 0.008) showed a statistically significant difference.,评价危重病患者病死率,Sakka等对373例危重病患者回顾性研究发现 高EVLW患者的病死率显著高于低EVLW患者 还发现EVLW与简明急性生理评分(SAPS)和急性生理和慢性健康评分（APACHE) 一样，是评价危重病患者病死率的独立而可靠的因素。,容量管理,基本目标 维持有效血容量 合适的心脏前负荷 预防和治疗肺水肿,容量监测现状,临床表现：BP, HR, 尿量, BUN/Cr 等 压力监测：飘浮导管（CVP/PAWP） 容量监测：TEE, CT, MRI，核素扫描,压力反映容量及肺水肿的局限性,心脏的顺应性 瓣膜功能 肺毛细血管通透性 机械通气对循环的影响,CVP/PAWP,CVP和PAWP与心脏容量状况之间相关性的可靠程度欠佳。 心肌顺应性降低的情况下，较少的容量增加会引起CVP和PAWP明显增高，而ITBV 不受心肌顺应性影响。 因此，ITBV比CVP和PAWP更能反映心脏容量负荷。,容量指标,胸腔内血管容量（ITBV） 血管外肺水(EVLW) 全心舒张末期容积（GEDV） 搏出量变异率（SVV）,EVLW与CVP/PAWP,Mitchell等将101例放置肺动脉漂浮导管的肺水肿患者随机分成两组 分别通过PAWP和EVLW进行液体管理，PAWP组将上限定为18 mmHg，EVLW组将上限定为7 mlKg，超过上限值就进行限液并使用利尿剂。 结果，EVLW组机械通气时间和住院时间较PAWP组明显缩短 提示, 根据EVLW进行肺水肿的液体管理可能比CVP和PAWP更为可靠。,胸腔内血管容量（ITBV）,The accuracy of intrathoracic blood volume (ITBV) as a preload index, instead of central venous pressure and wedge pressure, has been demonstrated Lichtwark-Ashoff M, et al.: Intensive Care Med 1992, 18:142-147. Lichtwark-Ashoff M, et al.: J Crit Care 1996, 11:180-188 Joachim Boldt: Critical Care 2002, 6:52-59,Fluid overload 透析与液体过负荷,To assess the dry weight of chronic hemodialysis (HD) patients The PiCCO system In 28 of the 42 patients (67%), elevated values of ELWI were found, indicating interstitial volume overload. 无液体过负荷的临床表现并非意味着已达到理想的dry weight There were significant correlations between ELWI and cardiac function index (p=0.003), global ejection fraction (p=0.012), ITBI (p=0.004), and GEDI (p=0.004) No significant relations among ELWI and mean arterial pressure (MAP), BNP, aldosterone, and renin were found. In conclusion, the use of ELWI is safe in chronic HD patients and identifies fluid-overloaded patients, who show no obvious signs of hypervolemia. The determination of ELWI is an excellent method to quantify the exact volume in chronic HD patients. Christian K