Hemodynamic alterations in dogs with shock induced by intravenous injection of heartworm extract.
To elucidate one way of the shock mechanisms, the hemodynamic alterations were examined in 7 dogs with heartworm (HW) extract-induced shock. The first alteration observed after injection of HW extract was a decrease in right ventricular end-diastolic pressure (RVEDP). After that, left ventricular (LV) end-diastolic pressure, LV systolic pressure, and LV dp/dt fell significantly, followed by a decrease in the cardiac output of all dogs to below the detectable level (1.00 l/min). Since RVEDP depends on blood flow into the right ventricle, the decrease in RVEDP means a reduction in venous return. Therefore, this study showed that the first trigger of a decrease in blood pressure in HW extract-induced shock is the reduction in venous return.
Kitoh
K
K
Division of Veterinary Medicine, Faculty of Agriculture, Gifu University, Japan.
Mikami
C
C
Kitagawa
H
H
Sasaki
Y
Y
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D004183:Dirofilaria immitis; D004283:Dog Diseases / Q000209:etiology / Q000503:physiopathology*; D004285:Dogs; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics / Q000502:physiology*; D008297:Male; D012769:Shock / Q000209:etiology / Q000503:physiopathology / Q000662:veterinary*; D014020:Tissue Extracts / Q000633:toxicity*
D014020:Tissue Extracts