CORE--CLINICAL

核心--临床

• 批准号: 6202636
• 负责人: Douglas MICHAEL SHASBY
• 金额: $ 21.82万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2000-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6202636
• 关键词: adult respiratory distress syndrome; bacterial disease; bacterial pneumonia; biomedical facility; blood toxicology; human mortality; human subject; inflammation; polymerase chain reaction; respiratory infections

While there are some optimistic reports, the mortality for ARDS remains near 50%. Of the patients who die, one half survive beyond the first three days. In these patients who survive more than 3 days, signs of persistent lung and systemic inflammation are associated with increased mortality. Early autopsy series detected a large number of unsuspected cases of bacterial infection of the lung in persons dying with ARDS. In more recent clinical studies culture of bronchoscopic samples from live patients without clinical signs of pneumonia have not yielded a high prevalence of results that meet strict criteria for pneumonia. However, a large fraction of samples did contain bacteria and the prevalence of samples with bacteria increased with time on the ventilator. In addition to bacterial colonization of the lung itself, translocation of bacteria across the intestinal wall occurs in severely ill patients, and especially those with shock. The use of broad spectrum antibiotics in patients with ARDS limits the sensitivity of strict quantitative culture criteria to accurately quantify the bacterial burden in ARDS patients. We hypothesize that a significant portion of the persistent acute inflammation present in the lungs of ARDS patients derives from bacteria which colonize the lung surfaces and/or translocate into the blood stream. In the case of bacteria which translocate into the blood stream the primed lung becomes the subject of a response similar to the Shwartzman phenomenon. Recent studies have not detected high levels of lung colonization or blood stream invasion by bacteria because of the ubiquitous use of broad spectrum antibiotics. We will measure bacterial burden in the lung and blood stream of ARDS patients using PCR for bacterial DNA, the sensitivity of which is not as limited by the presence of antibiotics. We will determine if the bacterial burden in the lung and blood as an independent predictor of mortality and if it correlates with indices of acute inflammation.

尽管有一些乐观的报告，但ARDS的死亡率仍然存在 接近50％。在死亡的患者中，一半的生存超过了前三个 天。在这些生存超过3天的患者中，持续的迹象 肺部和全身性炎症与死亡率增加有关。 早期的尸检系列检测到大量未引起的病例 肺部死于ARD的人的细菌感染。在最近的 来自活着患者的支气管镜样品的临床研究培养 没有肺炎的临床迹象 符合严格肺炎标准的结果。但是，很大一部分 样品的确包含细菌和样本的流行率 细菌随着呼吸机上的时间增加。除了细菌 肺本身的定殖，细菌的易位 肠壁发生在严重患者，尤其是患者 震惊。在具有ARDS极限的患者中使用广谱抗生素 严格的定量培养标准的敏感性准确 量化ARDS患者的细菌负担。 我们假设很大一部分持久性急性 ARDS患者肺中存在的炎症来自细菌 在肺表面和/或转运到血液中。 在细菌的情况下，将血液转移到血流中 肺成为类似于Shwartzman的反应的主题 现象。最近的研究尚未检测到高水平的肺 细菌的定殖或血流侵袭 无处不在的广谱抗生素。我们将测量细菌 使用PCR的ARDS患者的肺和血流负担 细菌DNA，其灵敏度不受存在的限制 抗生素。我们将确定肺部的细菌负担是否 血液作为死亡率的独立预测指标，是否与 急性炎症指标。