Endotoxin shock in newborn dogs: serial hemodynamic studies.
Using a newly modified dye dilution method for cardiac output determination, we successfully performed frequent serial hemodynamic measurements in newborn dogs to characterize hemodynamic changes in endotoxin shock in neonates. Sixty-seven mongrel newborn dogs (2 to 20 days old, 300 to 1500 gm) were divided into four groups: group 1 (2 to 20 days old, 300 to 1500 gm) received normal saline solution, group 2 (2 to 10 days old, 300 to 800 gm) received 1.5 mg/kg of Escherichia coli lipopolysaccharide (LPS), group 3 (2 to 10 days old, 300 to 800 gm) received 10 mg/kg of LPS, and group 4 (11 to 20 days old, 801 to 1500 gm) received 10 mg/kg of LPS. Cardiac output, heart rate, mean arterial pressure, systemic vascular resistance, and minute work were measured serially after endotoxin administration for 4 hours. Despite extensive manipulation, these measurements were stable in controls throughout the length of the study. Endotoxin, administered at two different doses of 1.5 mg/kg and 10 mg/kg, had profound effects on hemodynamic responses. These effects included a significant dose-related fall in cardiac output, minimal changes in heart rate, and a marked rise in systemic vascular resistance. The hemodynamic changes reported in this study lend additional support to the hypothesis that maturational factors are involved in the hemodynamic response to LPS.
Goto
M
M
Department of Pediatrics, Loyola University Stritch School of Medicine, Maywood, IL 60153.
Griffin
A J
AJ
Chiemmongkoltip
P
P
Onouchi
Z
Z
Bernheim
B
B
D000818:Animals; D000831:Animals, Newborn; D001794:Blood Pressure; D002302:Cardiac Output; D004285:Dogs; D006339:Heart Rate; D006439:Hemodynamics; D008070:Lipopolysaccharides / Q000633:toxicity*; D012772:Shock, Septic / Q000503:physiopathology*; D014655:Vascular Resistance
D008070:Lipopolysaccharides