成人呼吸窘迫综合症_图文.ppt

ARDS 易 难 * * Figure 3. Histologic and ultrastructural analysis of the injured lung has been integral to current concepts of pathogenesis of ALI/ARDS. (A) A low-power light micrograph of a lung biopsy specimen collected 2 d after the onset of ALI/ARDS secondary to gram-negative sepsis demonstrates key features of diffuse alveolar damage, including hyaline membranes, inflammation, intraalveolar red cells and neutrophils, and thickening of the alveolar–capillary membrane. (B) A higher-power view of a different field illustrates a dense hyaline membrane and diffuse alveolar inflammation. Polymorphonuclear leukocytes are imbedded in the proteinaceous hyaline membrane structure (black arrows). The white arrow points to the edge of an adjacent alveolus, which contains myeloid leukocytes (C) An electron micrograph from a classic analysis of ALI/ARDS showing injury to the capillary endothelium and the alveolar epithelium. LC refers to a leukocyte (a neutrophil) within the capillary lumen. EC designates enythrocytes. EN shows blebbing of the capillary endothelium. BM refers to exposed basement membrane where the epithelium has been denuded. C refers the capillary. A refers to the alveolar space. ARDS的病理基础是由多种炎症细胞(巨噬细胞、嗜中性粒细胞和淋巴细胞等)介导的肺脏局部炎性反应和炎症反应失控所致的肺毛细血管膜损伤。其主要病理特征为由肺微血管通透性增高而导致的肺泡渗出液中富含蛋白质的肺水肿及透明膜形成，可伴有肺间质纤维化。 * * * * In 1967, Ashbaugh et al. [1] from the University of Colorado Medical Center in Denver, USA, described for the first time a syndrome that they termed the acute respiratory distress syndrome (ARDS). * * the basic tenets of ARDS, namely increased lung permeability, increased extravascular lung water and lung inflammation, are not specifically identified by this definition. 没有体现ARDS的本质（肺通透性增加、血管外肺水增多，肺炎症反应） * * Importance to Researchers Importance to Clinicians Importance to Administrators * 在不同的吸氧浓度下，动脉氧分压与吸氧浓度之间一定是线性关系吗？ 也就是说，同一个病人同一时间点，我给不同的吸氧浓度情况下，氧合指数一定是一个定值吗？ * * * 既然我们所理解的氧合指数不可靠，那么AECC标准中其它的指标可靠吗？让们看看胸片的判断可