Cardiac function in an ovine model of endotoxemia.
Eight awake sheep were monitored with ultrasonic crystals, positioned at the anterior and posterior left ventricular wall. A left-sided intraventricular pressure transducer and a right ventricular ejection fraction catheter were positioned in the right and left hearts, respectively. After administration of endotoxin (Escherichia coli, LPS 1.5 micrograms/kg in 30 min), the hemodynamic variables showed a triphasic course. Phase I, (0-1 hr post LPS) was characterized by an increased pulmonary artery pressure and a decreased right ventricular ejection fraction. The inability of the right ventricle to compensate for the increased preload resulted in a fall of the left ventricular preload, stroke volume, and cardiac output. Three hours after LPS administration a second drop of the cardiac output was noted (phase II). This occurred as a result of a fall in preload. Eight hours post LPS a hyperdynamic phase (phase III) was distinguished, with a high cardiac output and a low systemic vascular resistance. During this time there was evidence of probable reduced myocardial contractility.
Redl
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Department of Anesthesiology, University of Texas Medical Branch, Galveston.
Newald
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J
Schlag
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Traber
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LD
Traber
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DL
D000818:Animals; D001794:Blood Pressure; D002302:Cardiac Output; D002319:Cardiovascular System / Q000503:physiopathology*; D004731:Endotoxins; D004926:Escherichia coli; D011651:Pulmonary Artery / Q000503:physiopathology; D012756:Sheep; D012772:Shock, Septic / Q000139:chemically induced / Q000503:physiopathology*; D013318:Stroke Volume; D014655:Vascular Resistance
D004731:Endotoxins