2015年ARDS-通气策略(宋立强)

1、,西京医院呼吸与危重医学科 宋立强,Pulmonary Protective Ventilation In ARDS,ARDS及其通气策略的新进展,ARDS的病理生理定义,急性呼吸窘迫综合征 （ Acute Respiratory Distress Syndrome，ARDS ） 心源性以外的各种肺内外致病因素 急性、进行性 缺氧性呼吸衰竭,导致,ARDS的发生机制？,ARDS是一种水循环障碍的“肺水肿”,“肺水肿”分类 (按照病因及发生机制),ARDS！,1.感染性肺水肿 (pulmonary edema due to infection),2.毒素吸入性肺水肿 (pulmonary ede

2、ma due to poison),3.淹溺性肺水肿 (pulmonary edema due to drowning),4.尿毒症性肺水肿 (pulmonary edema in uremia),5.氧中毒肺水肿 (pulmonary edema due to oxygen toxicity), 通透性肺水肿 病因及分类,ARDS肺水肿的 成分： 富含蛋白 细胞碎片 未激活的PS 中性粒细胞 巨噬细胞 炎症介质 .,Apex,Hilum,Base,病变分布有重力依赖性， 从肺前部到背部 1. 正常区30% 2. 陷闭区2030% 3. 实变区4050%,病理生理变化 间歇性分流 切变力损伤

3、肺循环阻力增加,病理生理变化 持续性分流 肺循环阻力增加,力学曲线变化 ,ARDS的临床诊断？,临床诊断标准的变迁 AECC定义,1967年，Ashbaugh等首先描述“成人中的急性呼吸窘迫” 1971年，Petty等正式命名“成人呼吸窘迫综合征（ARDS）” 1992年，美欧共识会（American-European Consensus Conference, AECC）,急性呼吸窘迫综合征（Acute Respiratory Disease Syndrome，ARDS） 首次提出ALI 提出AECC标准,AECC诊断标准的局限,An early PEEP/FIO2 trial identi

4、fies different degrees of lung injury in patients with acute respiratory distress syndrome. Am J Respir Crit Care Med.2007； 15;176(8):795-804.,例： ARDS患者在不同通气条件下的变化,在（day1）时间点 FiO20.5 + PEEP 10， 30min条件下 重新分类为ARDS, ALI, ARF,29%ARDS患者PAWP18mmHg（或CVP升高）, 而其中97%PAWP升高的ARDS患者中有正常的心脏功能。结论：PAWP或CVP升高不能作为AR

5、DS的排除标准。,Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. N Engl J Med.2006 May 25;354(21):2213-24.,CVP,PAWP,例：ARDS与PAWP、CVP,8,18,Berlin Definition 2012 柏林定义,传统机械通气的肺损伤？,Ventilator Induced Lung Injury，VILI,Overdistention 过度扩张 Barotrauma压力伤 Volutrauma容量伤 Recrui

6、tment/Derecruitment Injury （Atlectrauma） 剪切伤/萎陷伤 Translocation of Cells 细胞形态移位 Biotrauma 生物伤 Oxidant Injury 氧中毒,OverdistentionBarotrauma 157:1721-5,ARDS的保护性通气策略？,Oxidant injury- keep FiO2 60 Barotrauma- keep alveolar inflation pressures 35 cm H2O Volutrauma- Baby lung concept or stretch injury Atele

7、ctrauma- repeated opening and closing Biotrauma- release of inflammatory mediators and bacterial translocation OPEN GENTLY AND KEEP THEM OPEN 温柔的打开肺泡，并保持开放,Principle原则,Whitehead T, Slutsky AS. Thorax. 2002;57:636,传统的肺保护性通气策略, 小潮气量 （6 mlkg理想体重） 允许性高碳酸血症 控制气道平台压30 cmH 2O 使用合适的PEEP,是迄今为止少有的被大规模随机对照研究证实

8、， 能降低ARDS患者死亡率的治疗措施。,提 高 治 疗 干 预 强 度,轻度ARDS,中度ARDS,严重ARDS,小潮气量通气,更高水平PEEP,无创通气,低-中水平PEEP,俯卧位通气,神经肌肉阻滞剂,高频振荡通气,ECCO2-R,ECMO,300 250 200 150 100 50,提纲：临床探讨的通气模式与参数,Tidal volume Plateau pressures pH PEEP VC vs PCV Recruitment maneuvers High-frequency oscillatory Prone positioning ECMO,潮气量 平台压 允许性高碳酸血症

9、呼气末正压 定容与定压 手法复张 高频振荡通气 俯卧位通气 体外膜氧合,肺通气保护策略在儿童ARDS中的应用,2000年 NEJM， 861名成人ARDS患者 治疗组：小潮气量（4-6ml/kg）,限制压力（平台压30cmH2O），允许性高碳酸血症但保持pH大于7.3 显著改善预后 病死率 39.8%31% 自主呼吸天数 10天12天 首次为小潮气量通气模式提供可靠的循证医学证据,小潮气量 Low Tidal Volume,ARDS Net. 2000,PLATEAU PRESSURES 低平台压,Hager DN et al. Tidal Volume Reduction in Patien

10、ts with Acute Lung Injury When Plateau Pressures Are Not High. AJRCCM 2005. Vol 172 1241-1245,多个研究比较,*,*,*,死亡率,787 patients from ARDS Network study,平台压,死 亡 率,30,平台压的调整策略,PEEP：较高的呼气末正压 (Meta),Briel M, Meade M, Mercat A, et al. Higher vs lower positive end-expiratory pressure in patients with acute lu

11、ng injury and acute respiratory distress syndrome. JAMA 2010;303(9):86573.,医院死亡率 ICU死亡率 气胸 气胸后死亡 脱机时间,允许性高碳酸血症的通气策略,33,pH值的调整策略,流程图,起始选择与设置,小潮气量+高PEEP,潮气量：VT of 8mL/kg vs VT of 1015 mL/kg PEEP：titrating PEEP as high as possible without increasing the maximal PEI to greater than 30 cm H2O,Purpose: To

12、 determine whether ventilation with low tidal volume (VT) and limited airway pressure or higher positive end-expiratory pressure (PEEP) improves outcomes for patients with ARDS or acute lung injury,住院死亡率,随访死亡率,气压伤,因严重低氧所致 抢救性治疗的应用率,抢救性治疗的死亡率,第1天的PaO2,研究结论,routine use of low VT tends to be benecial i

13、n all patients with acute lung injury or ARDS because this ventilation strategy improved hospital mortality. Higher PEEP strategies during lower VT ventilation did not improve hospital mortality and cannot be recommended in unselected patients with acute lung injury or ARDS. Higher PEEP strategies d

14、uring lower VT ventilation may prevent life-threatening hypoxemia.,VCV vs PCV 定容与定压,PCV的优点: variable flow so more comfortable if dys-synchrony, prolong i time for oxygenation, control peak pressures,RCT multicenter, 79 patients with ARDS PCV (n-37) versus VCV (n=42). P plat 35 cm H2O No difference i

15、n mortality trend to more renal failure in VCV group BUT patients in VCV group had a higher in-house mortality related to higher number of extra-pulmonary organ failures (78% vs 51%) （TV 8cc/kg of weight）,RECRUITMENT 肺复张,A recent systematic review analyzed 40 studies that evaluated RMs;（4 were RCTs,

16、 32 prospective studies, and 4 retrospective cohort studies） The sustained inflation method 45%：CPAP of 3550 cm H2O for 2040 seconds 23%：high pressure control 20%：incremental PEEP 10%：high VT/sigh,Fan E, Wilcox ME, Brower RG, et al. Recruitment maneuvers for acute lung injury.Am J Respir Crit Care M

17、ed 2008;178(11):115663.,Current evidence suggests that that RMs should not be routinely used on all ARDS patients unless severe hypoxemia persists or as a rescue maneuver to overcome severe hypoxemia, to open the lung when setting PEEP, or following evidence of acute lung derecruitment such as a ven

18、tilator circuit disconnect 结论：RM不常规用在所有的ARDS患者，除非持续的严重低氧血症，或者做为严重低氧血症的一种肺开放手段（设置PEEP），或者由于管路断开出现急性肺陷闭,Fan E, Wilcox ME, Brower RG, et al. Recruitment maneuvers for acute lung injury.Am J Respir Crit Care Med 2008;178(11):115663.,PRONE POSITIONING俯卧位通气,Computed tomography scan of the lungs showing AR

19、DS when the patient is lying supine (left) and prone (right).,Gattinoni L, Protti A. Ventilation in the prone position:for some but not for all? CMAJ 2008;178(9):11746),The Prone-Supine II Study is the largest clinical trial (N 5342) in adult ARDS patients, conducted in 23 centers in Italy and 2 in

20、Spain 20 hours/day Similar 28-day mortality- 31.0% vs 32.8%; RR 0.97; (95% CI 0.841.13; P=0.72) Mortality in severe hypoxemia was decreased in the prone group-37.8% in the prone group and 46.1% in the supine group (RR, 0.87; 95% CI, 0.661.14 P =0.31),Taccone P, Pesenti A, Latini R, et al. Prone posi

21、tioning in patients with moderate and severe acute respiratory distress syndrome: a randomized controlled trial. JAMA 2009;302:197784.,Mortality,Effect of mechanical ventilation in the prone position on clinical outcomes in patients with acute hypoxemic respiratory failure: a systematic review and m

22、eta-analysis. CMAJ 2008;178(8):115361,短时间,长时间,P=0.32,P=0.68,Oxygenation,Sud S, Sud M,Friedrich JO, et al. Effect of mechanical ventilation in the prone position on clinical outcomes in patients with acute hypoxemic respiratory failure: a systematic review and meta-analysis. CMAJ 2008;178(8):115361,第

23、1天,第2天,第3天,P0.001,P0.001,P0.001,Complications,镇静肌松 气道阻塞 短暂SpO2下降 呕吐 低血压 心律失常 深静脉脱落 气管插管移位 气管切开移位,High-frequency oscillatory ventilation, HFOV高频振荡通气,54,Meta分析结论 维持高平均气道压以保持肺复张，避免肺泡周期性开放、闭合。 均为小样本研究。 2010BMJmeta-analysis：系统分析多项随机对照临床研究，HFOV提高氧合指数、显著降低死亡率。,Sud S, Sud M, Friedrich JO, et al. High freque

24、ncy oscillation in patients with acute lung injury and acute respiratory distress syndrome (ARDS): systematic review and meta-analysis. BMJ 2010; 340:c2327.,ECMO体外膜氧合,ECMO is supportive care and is not intended as a primary ARDS treatment CESAR trial- Patients were randomized to either conventional

25、care at 1 of 68 tertiary care centers or to a single center using a treatment protocol that included ECMO The trial was stopped for efficacy after 180 patients Survival without severe disability at 6 months was 47% vs 63% at 6 months,Peek GJ, Mugford M, Tiruvoipati R, et al. Efficacy and economic as

26、sessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial. Lancet 2009;374(9698):135163.,58,NPPV 无创通气,中国危重病急救医学.2006;18(12 ):706-710,预计病情能够短期缓解的早期ALI/ARDS患者可考虑应用NIV。(B级) 合并免疫功能低下的ALI/ARDS 患者早期可首先试用NIV。(B级) 应用NIV 治疗ALI/ARDS 应严密监测患者的生命体征及治疗反应。意识不清、休克、气道自洁能力障碍的ALI/ARDS 患者不宜应用NIV。(C 级),NPPV被推荐的适应症及强度,高,中,低,AECOPD 急性心源性肺水肿 免疫力低下呼衰 COPD脱机,术后呼衰