1、,西京醫(yī)院呼吸與危重醫(yī)學科 宋立強,Pulmonary Protective Ventilation In ARDS,ARDS及其通氣策略的新進展,ARDS的病理生理定義,急性呼吸窘迫綜合征 （ Acute Respiratory Distress Syndrome，ARDS ） 心源性以外的各種肺內(nèi)外致病因素 急性、進行性 缺氧性呼吸衰竭,導致,ARDS的發(fā)生機制？,1 肺間質(zhì) 2 肺泡,ARDS是一種水循環(huán)障礙的“肺水腫”,“肺水腫”分類 (按照病因及發(fā)生機制),ARDS！,1.感染性肺水腫 (pulmonary edema due to infection),2.毒素吸入性肺水腫 (pu

2、lmonary edema due to poison),3.淹溺性肺水腫 (pulmonary edema due to drowning),4.尿毒癥性肺水腫 (pulmonary edema in uremia),5.氧中毒肺水腫 (pulmonary edema due to oxygen toxicity), 通透性肺水腫 病因及分類,ARDS肺水腫的 成分： 富含蛋白 細胞碎片 未激活的PS 中性粒細胞 巨噬細胞 炎癥介質(zhì) .,Apex,Hilum,Base,病變分布有重力依賴性， 從肺前部到背部 1. 正常區(qū)30% 2. 陷閉區(qū)2030% 3. 實變區(qū)4050%,病理生理變化 間

3、歇性分流 切變力損傷 肺循環(huán)阻力增加,病理生理變化 持續(xù)性分流 肺循環(huán)阻力增加,力學曲線變化 ,ARDS的臨床診斷？,臨床診斷標準的變遷 AECC定義,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“成人呼吸窘迫綜合征（ARDS）” 1992年，美歐共識會（American-European Consensus Conference, AECC）,急性呼吸窘迫綜合征（Acute Respiratory Disease Syndrome，ARDS） 首次提出ALI 提出AECC標準,AECC診斷標準的局限,An early PEEP/FIO2 t

4、rial identifies 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患者在不同通氣條件下的變化,在（day1）時間點 FiO20.5 + PEEP 10， 30min條件下 重新分類為ARDS, ALI, ARF,29%ARDS患者PAWP18mmHg（或CVP升高）, 而其中97%PAWP升高的ARDS患者中有正常的心臟功能。結(jié)論：PAWP或

5、CVP升高不能作為ARDS的排除標準。,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與PAWP、CVP,8,18,Berlin Definition 2012 柏林定義,傳統(tǒng)機械通氣的肺損傷？,Ventilator Induced Lung Injury，VILI,Overdistention 過度擴張 Barotrauma壓力傷 Volutraum

6、a容量傷 Recruitment/Derecruitment Injury （Atlectrauma） 剪切傷/萎陷傷 Translocation of Cells 細胞形態(tài)移位 Biotrauma 生物傷 Oxidant Injury 氧中毒,OverdistentionBarotrauma 157:1721-5,ARDS的保護性通氣策略？,Oxidant injury- keep FiO2 60 Barotrauma- keep alveolar inflation pressures 35 cm H2O Volutrauma- Baby lung concept or stretch i

7、njury Atelectrauma- repeated opening and closing Biotrauma- release of inflammatory mediators and bacterial translocation OPEN GENTLY AND KEEP THEM OPEN 溫柔的打開肺泡，并保持開放,Principle原則,Whitehead T, Slutsky AS. Thorax. 2002;57:636,傳統(tǒng)的肺保護性通氣策略, 小潮氣量 （6 mlkg理想體重） 允許性高碳酸血癥 控制氣道平臺壓30 cmH 2O 使用合適的PEEP,是迄今為止少有的被

8、大規(guī)模隨機對照研究證實， 能降低ARDS患者死亡率的治療措施。,提 高 治 療 干 預 強 度,輕度ARDS,中度ARDS,嚴重ARDS,小潮氣量通氣,更高水平PEEP,無創(chuàng)通氣,低-中水平PEEP,俯臥位通氣,神經(jīng)肌肉阻滯劑,高頻振蕩通氣,ECCO2-R,ECMO,300 250 200 150 100 50,提綱：臨床探討的通氣模式與參數(shù),Tidal volume Plateau pressures pH PEEP VC vs PCV Recruitment maneuvers High-frequency oscillatory Prone positioning ECMO,潮氣量 平臺

9、壓 允許性高碳酸血癥 呼氣末正壓 定容與定壓 手法復張 高頻振蕩通氣 俯臥位通氣 體外膜氧合,肺通氣保護策略在兒童ARDS中的應用,2000年 NEJM， 861名成人ARDS患者 治療組：小潮氣量（4-6ml/kg）,限制壓力（平臺壓30cmH2O），允許性高碳酸血癥但保持pH大于7.3 顯著改善預后 病死率 39.8%31% 自主呼吸天數(shù) 10天12天 首次為小潮氣量通氣模式提供可靠的循證醫(yī)學證據(jù),小潮氣量 Low Tidal Volume,ARDS Net. 2000,PLATEAU PRESSURES 低平臺壓,Hager DN et al. Tidal Volume Reductio

10、n in Patients with Acute Lung Injury When Plateau Pressures Are Not High. AJRCCM 2005. Vol 172 1241-1245,多個研究比較,*,*,*,死亡率,787 patients from ARDS Network study,平臺壓,死 亡 率,30,平臺壓的調(diào)整策略,PEEP：較高的呼氣末正壓 (Meta),Briel M, Meade M, Mercat A, et al. Higher vs lower positive end-expiratory pressure in patients wi

11、th acute lung injury and acute respiratory distress syndrome. JAMA 2010;303(9):86573.,醫(yī)院死亡率 ICU死亡率 氣胸 氣胸后死亡 脫機時間,允許性高碳酸血癥的通氣策略,33,pH值的調(diào)整策略,流程圖,起始選擇與設置,小潮氣量+高PEEP,潮氣量：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,

12、Purpose: To 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,隨訪死亡率,氣壓傷,因嚴重低氧所致 搶救性治療的應用率,搶救性治療的死亡率,第1天的PaO2,研究結(jié)論,routine use of low VT tends to be

13、 benecial in 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 s

14、trategies during lower VT ventilation may prevent life-threatening hypoxemia.,VCV vs PCV 定容與定壓,PCV的優(yōu)點: 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 d

15、ifference in 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 肺復張,A recent systematic review analyzed 40 studies that evaluated RMs;（4

16、 were RCTs, 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

17、Crit Care Med 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 su

18、ch as a ventilator circuit disconnect 結(jié)論：RM不常規(guī)用在所有的ARDS患者，除非持續(xù)的嚴重低氧血癥，或者做為嚴重低氧血癥的一種肺開放手段（設置PEEP），或者由于管路斷開出現(xiàn)急性肺陷閉,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俯臥位通氣,Computed tomography scan of the lungs

19、 showing ARDS 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 Ital

20、y and 2 in 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.

21、 Prone positioning 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 r

22、eview and meta-analysis. CMAJ 2008;178(8):115361,短時間,長時間,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(

23、8):115361,第1天,第2天,第3天,P0.001,P0.001,P0.001,Complications,鎮(zhèn)靜肌松 氣道阻塞 短暫SpO2下降 嘔吐 低血壓 心律失常 深靜脈脫落 氣管插管移位 氣管切開移位,High-frequency oscillatory ventilation, HFOV高頻振蕩通氣,54,Meta分析結(jié)論 維持高平均氣道壓以保持肺復張，避免肺泡周期性開放、閉合。 均為小樣本研究。 2010BMJmeta-analysis：系統(tǒng)分析多項隨機對照臨床研究，HFOV提高氧合指數(shù)、顯著降低死亡率。,Sud S, Sud M, Friedrich JO, et al.

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

25、nventional 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

26、economic assessment 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 無創(chuàng)通氣,中國危重病急救醫(yī)學.2006;18(12 ):706-710,預計病情能夠短期緩解的早期ALI/ARDS患者可考慮應用NIV。(B級) 合并免疫功能低下的ALI/ARDS 患者早期可首先試用NIV。(B級) 應用NIV 治療ALI/ARDS 應嚴密監(jiān)測患者的生命體征及治療反應。意識不清、休克、氣道自潔能力障礙的ALI/ARDS 患者不宜應用NIV。(C 級),NPPV被推薦的適應癥及強度,高,中,低,AECOPD 急性心源性肺水腫 免疫力低下呼衰 COPD脫機,術(shù)后呼