ARDS肺可复张性评估.ppt

ARDS肺可复张性评估,山东大学齐鲁医院 重症医学科 张帆,ARDS的病理生理,病理学特点：肺组织损伤的不均一性,N Engl J Med, 2006,354:1775-1786,HEART,SP,ARDS肺保护性通气,1.小潮气量/PHC 2. RM +最佳PEEP,肺可复张性,Lung tissue in which aeretion can be restored N Engl J Med, 2006, 354:1775-1786 在压力的作用下，不通气的肺泡恢复通气的能力 Crit Care Med, 2011, 39: 1839-1840,肺复张的生理作用,促进塌陷肺泡复张，增加肺容积 提升肺顺应性 降低肺内分流 减轻肺内、肺外器官的炎症反应,中国危重病急救医学，2004,16:603-607,肺复张手法,肺可复张性初步评估,N Engl J Med, 2006 :1775-1786,肺可复张性的评估办法,CT评价肺通气的金标准,“diffuse” ARDS,“lobar” ARDS,Crit Care Med 2003;31Suppl.:S285S295,CT定量分析定量评价肺水肿和通气,张帆，吴大玮， BioMedical Engineering OnLine 2014, 13:30,肺可复张性的评价Gattinoni method,The percentage of potentially recruitable lung9% 为高可复张性,The percentage of potentially recruitable lung：气道压力由5cmH2O升至45cmH2O时，不通气区的减少占全肺重量的百分比,N Engl J Med 2006;354:1775-86,PEEP-induced alveolar recruitment (RECALV) was expressed as percentage of variation of the weight of the nonaerated lung parenchyma: RECALV (%)=(WZEEP-WPEEP)/WZEEP,N Engl J Med 2006;354:1775-86,肺可复张性的评价Gattinoni method,The decrease in the percentage of nonaerated lung tissue as PEEP was raised from 5cmH2O to 15cmH2O was highly correlated with the percentage of potentially recruitable lung (r2 = 0.72, P0.001),肺可复张性的评价 The CT Scan ARDS Study Group method,“diffuse” ARDS,“lobar” ARDS,Am J Respir Crit Care Med 2001:14441450,PEEP-induced alveolar recruitment was computed as the increase in gas volume within the poorly and nonaerated lung regions following PEEP divided by the FRC measured in ZEEP conditions RECALV (%) = (VGas PEEP VGas ZEEP)/FRCZEEP,P-V曲线评估肺可复张性,Critical Care 2008, 12:R7,EELVZEEP：ZEEP时的呼气末肺容积 ILV-10、ELV-10：气道压力10cmH2O，吸气/呼气支对应的肺容积 TLC：气道压力40cmH2O时肺总量 MH： maximal volume hysteresis，最大闭陷容积,MH/TLC与肺力学及血气分析的相关性,MH/TLC与EELV、Crs、PaCO2的变化明显相关（R2分别为0.55，0.57 and 0.36，P 0.05) MH/TLC 与PaO2的变化之间未见明显的相关性 (R2 = 0.05，P 0.26),Critical Care 2008, 12:R7,MH/TLC评价肺可复张性的敏感性和特异性,MH/TLC 预测肺复张后EELV改善的敏感度达 1.0，特异度0.85 预测Crs改善的敏感度和特异度0.88 、1.0 PaCO2 的改善为0.78 、0.60 PaO2 的改善为1.0 、0.69,Critical Care 2008, 12:R7,P-V曲线评估肺可复张性与CT对比,Crit Care, 2006, 10:R95,Crit Care, 2006, 10:R95,P-V曲线评估肺可复张性与CT对比,P-V曲线计算FRC与CT计算的肺泡闭陷容积呈明显的相关性和良好的一致性,呼气末肺容积（EELV）,P-V曲线与EELV的一致性良好,EIT可以显示肺复张后各区域呼气末肺容积的变化,EELV评估肺可复张性,Journal of Critical Care,2013,28: 534.e1534.e5,肺复张EELV的增加与氧合指数的改善明显相关,EELV评估肺可复张性,The optimal cutoff value of the EELV to predict a 15% change in the P/F ratio was 9.25% (sensitivity, 86.7%; specificity, 84.4%),Journal of Critical Care,2013,28: 534.e1534.e5,肺牵张指数（Stress Index）,Y=atb +c,容量控制通气吸气支形状与肺牵张指数的关系,肺牵张指数评估肺可复张性,J Surg Res2013 Nov;185(1):347-52.,Electrical Impedance Tomography (EIT),肺组织的电学特征受气体含量的影响，肺内气体含量的改变导致电阻抗的变化,基本信息 - 通气分布情况 - 局部位置的呼气末肺容量的变化(EELV),EIT可以显示肺复张后各区域呼气末肺容积的变化,EIT可以显示肺复张后通气分布的变化,经PEEP递增法行肺复张后，全肺的阻抗变化明显增加，反应全肺的通气量增加。,经肺复张后，肺通气明显改善，尤其是重力依赖区通气明显增加，PEEP降低时，重力依赖区通气首先出现下降，与CT变化基本一致。,Crit Care Med 2012;40:903911,EIT可以评价肺的可复张性，随着PEEP的升高，全肺通气得到改善，重力依赖区通气明显增加，与CT的变化基本一致。,EIT使局部肺通气的床旁评估成为现实： 区域1代表非重力依赖区，通气量始终较重力依赖区占有优势，当PEEP由30cmH2O开始下降时出现通气量的一过性增高，说明存在局部肺泡的过度通气； 区域4代表重力依赖区，在PEEP升高至20cmH2O时出现通气量的突然增加，给予表面活性物质治疗后，肺泡开放的阈值降低至10cmH2O。,ARDS肺部超声,J Am Soc Echocardiogr 2006;19:356-363,ARDS肺部超声,normal lung,interstitial syndrome,严重肺水肿的超声表现,组织样征,碎片征,ARDS肺部超声的演变,Cardiovascular Ultrasound 2011, 9:6,肺复张前后的肺部超声,Respir Care, 2012 ,57(5):773-81,超声评价肺的可复张性,Four ultrasound aeration patterns were defined: (1) normal aeration(N): presence of lung sliding with A lines or fewer than two isolated B lines (2) moderate loss of lung aeration: multiple well-defined B lines(B1 lines) (3) severe loss of lung aeration: multiple coalescent B lines (B2 lines) (4) lung consolidation (C): the presence of a tissue pattern characterized by dynamic air bronchograms,Am J Respir Crit Care Med, 2011,183:341-347,Ultrasound Reaeration Score,Am J Respir Crit Care Med, 2011,183:341-347,PEEP诱导肺复张的超声表现,Am J Respir Crit Care Med, 2011,183:341-347,肺部超声法与其他评估方法的比较,Am J Respir Crit Care Med, 2011,183:341-347,肺部超声评价肺可复张性,优点 即时操作，无镇静肌松要求 可用于重力依赖区或非重力依赖区肺复张效果的评估,缺点 肺非静态，可能低估肺复张状况 患者因素影响准确性（胸壁皮下脂肪厚度、胸壁皮下气肿等） 受操作者熟练程度限制 不能区分正常通气或过度通气，不能作为肺复张评价的唯一指标,Am J Respir Crit Care Med, 2011,183:341-347,病例摘要,患者女，20岁，因促排卵药物治疗后“卵巢过度刺激综合征”，并出现高热，血小板减少至0109/L，由120送我院急诊。 查体：贫血貌，全身紫癜，腹膨隆，压痛伴反跳痛，腹水征阳性。,急症超声,左卵巢72mm56mm，内见62mm52mm低回声团块， 盆腹腔积液，内见细点状回声，深60mm 考虑左卵巢黄