EFFECTS OF VENTILATORY MODE ON DIAPHRAGMATIC BLOOD FLOW DURING ENDOTOXEMIA

本研究旨在探讨小剂量内毒素(2µg/kg)对自主呼吸犬呼吸肌血流量的影响。彩色微球示踪技术测量横隔膜、其他呼吸肌、肾脏和消化道的血流量。呼吸功由食道压力-潮气量曲线由肺监护仪CP-100(ATOM公司)计算。注射内毒素后2小时，心输出量和血压分别为对照组的54%和56%。即使心输出量确实减少，流向横隔肌和其他呼吸肌的血流量也增加了大约3倍。肾血流量和消化道血流量减少约60%。呼吸功增加48%。提示当发生细菌感染时，虽然临床表现稍有变化，但由于早期向呼吸肌的血液分布增多，肾脏和消化道的血流相对处于低灌流状态。如果持续低灌注状态，则会发生肾、消化道等器官功能不全，提示在多器官衰竭时发生了潜能的发展。我们的结论是，内毒素影响了呼吸肌和其他主要器官之间的血流分配，我们将在未来研究什么样的人工通气是合适的，什么样的药物治疗更有效。

This study was designed to examine the effects of low dose endotoxin (2 mug/kg) on respiratory muscle blood flow in spontaneously breathing dogs. Blood flow to diaphragm, other respiratory muscles, kidney, and alimentary canal was measured by colored microsphere tracing technique. The work of breathing was calculated from esophageal pressure-tidal volume curve by using pulmonary monitor CP-100 (ATOM Co.). Two hours after endotoxin administration, cardiac output and blood pressure amounted to 54% and 56% of the control value, respectively. And even if cardiac output did decrement, the blood flow to diaphragm and other respiratory muscles increased in approximately 3 times. The renal blood flow and the alimentary canal blood flow did decrement in approximately 60%. The work of breathing increased by 48% of control value. These data suggested that when bacterial infection has occurred, the blood flow to the kidney and alimentary canal was become low perfusion state relatively because of increment of the blood distribution to the respiratory muscles from early stage thought clinical manifestation was slightly changes. If low perfusion state lasts, organ incompetence such as kidney, alimentary canal happens, and suggests potency developing in multiple organ failure. We conclude that blood flow distribution between the respiratory muscles and other major organs was affected by endotoxin administration.We will examine what kind of artificial ventilation is appropriate and what kind of drug therapy is more effective in future.