ARDS肺复张的测定.pptxVIP

ARDS肺复张的测定;第2页/共88页;第3页/共88页;内容提要;Lung volume decreased markedly (TLC, VC, TV, FRC) ---alveolar edema ---pulmonary surfactant ---Interstitial pumonary edema depress brochiole and induce spasm Compliance reduced significantly Ventilation/perfusion mismatch ---intrapulmonary shunt and dead space like effects;CT scan 70-80% 的肺野呈现高密度区 分布：下垂部位(dependent field) 提示： 参与通气肺泡明显减少(20-30%) 肺损伤具有不均一性;A and C finding in the acute or exudative phase;肺容积/顺应性明显降低;Reduced range of volume excursion: Low compliance Flattening at low and high volumes: Lower and upper inflection points Bigatello: Br J Anaest 1996;Upper and Lower Inflection Points;通气/血流失调;Imagine the Hardness to Blow up a Ballon ...;Sustain inflation Sigh 小潮气量通气—PHC, 避免肺泡过度膨胀 最佳PEEP－避免剪切力(Shear force)性损害 ; ;内容提要;P－V曲线法; P－V曲线法;等压法;等压法;P-V曲线法与等压法的比较;肺复张容积测定—P-V曲线法;CT method;CT法--Gattinoni ; 原理 充气不良区(?100Hu~500Hu)、正常充气区(?500Hu~ ?900Hu)、无充气区(?100Hu~+100Hu)和过度充气区(?900Hu~?1000Hu)。肺泡复张，充气不良和正常充气肺区体积增加 方法 ZEEP和PEEP呼气末螺旋CT，根据层面厚度计算不同CT值肺体积，肺复张后充气不良与正常充气肺组织体积增加值;Gattinoni’s vs Rouby’s CT法比较;CT methods: Rouby vs Gattinoni;内容提要;ARDS肺不张的影响因素---附加静水压;ARDS下肺气体含量明显降低;CT section lcated 5 cm below the carina No differences were observed in the percentage of lower lobes located beneath the heart in two groups;Cardiac mass and volume in ARDS;心脏下肺叶气体量明显降低ARDS –73% vs NS –21%;塌陷肺泡的分布;Lung morphology pattern ;Diffuse distribution;ARDS肺复张应用;内容提要;SI前后绵羊复张容积的变化;SI有效组绵羊肺气体交换变化;潮气量对肺复张的影响;小潮气量通气的局限性;Mean Airway pressure 5 cm H2O;Mean Airway pressure 25 cm H2O;Mean Airway Pressure 40 cm H2O;不同VT的肺复张容积;内容提要;PEEP效应的影响因素---附加静水压与心脏的影响;Rothen H. et al. Br J Anaesth 1993:71:788-795;PEEP诱导recruitment的分布;PEEP导致overdistention的分布;PEEP效应的影响因素---塌陷肺泡的分布范围;Diffuse: Equal loss of aeration to the upper and lower lobes;Local: Loss of aeration predominating in lower lobes;Effect of PEEP on recruitment and overdistention;PEEP效应的影响因素---LIP的影响;绵羊有无LIP组PEEP复张容积;有无LIP患者的复张容积