[Influence of induced hyperthermia on intestinal blood flow, translocation of endotoxin and other factors in mongrel dogs].
This study was undertaken to investigate the effects of induced hyperthermia over 3 hr at 42.5 degrees C on intestinal blood flow, plasma endotoxin, cardiovascular system and other factors under a constant CVP level in 38 mature mongrel dogs. During hyperthermia, blood flow of the small intestine and colon showed no remarkable changes. The perfusion rates (blood flow/CI) showed a downward trend above 42 degrees C but there were no significant changes. At 42.5 degrees C, plasma endotoxin level in 9 of 14 dogs increased over 100 pg.ml-1 on the quantitative analysis. On qualitative analysis, 10 of 16 dogs that were positive for plasma endotoxin did not survive. The cardiac index increased gradually at temperature above 40 degrees C and increased significantly during hyperthermia at 42 degrees C and 42.5 degrees C. It then decreased gradually. The platelet counts decreased significantly at 42.5 degrees C over 1 hour, and white blood cell counts increased significantly at 42 degrees C and 42.5 degrees C, decreasing gradually thereafter. The red cell counts showed no significant change. Blood sugar level decreased significantly during hyperthermia at 42.5 degrees C and 42.5 degrees C for 1 hour. Lactate level increased significantly after hyperthermia at 42.5 degrees C for 1 hour, and pH decreased significantly over 3 hours at 42.5 degrees C. However, PaO2 was always maintained over 300 mmHg, and PaCO2 was maintained at 35-40 mmHg. Form the above results, it is conceivable that hyperthermia may have led to leakage of endotoxin into the systemic circulation, because reduced splanchnic blood flow and hypoxemia were not observed. The endotoxemia may be a contributing factor in the pathogenesis of heat stroke.
Hayano
Y
Y
Department of Anesthesiology, Medical College of Oita.
D000818:Animals; D001772:Blood Cell Count; D002302:Cardiac Output / Q000502:physiology; D004285:Dogs; D004731:Endotoxins / Q000097:blood*; D006979:Hyperthermia, Induced; D007422:Intestines / Q000098:blood supply*; D012039:Regional Blood Flow
D004731:Endotoxins