Detection of the 'hyperdynamic state' of sepsis in the baboon during lethal E. coli infusion

This study was designed to document the early responses of the baboon to LD100 E. coli infusion with an emphasis on cardiovascular, respiratory, and metabolic alterations. Adult baboons were anesthetized, catheterized aseptically to monitor cardiopulmonary and systemic parameters, and infused with LD100 E. coli intravenously for 2 hours. Cardiac output was determined with an Edwards Laboratory Thermodilution Cardiac Output Computer. Oxygen contents of systemic and pulmonary artery blood were determined with a Van Slyke Manometric Apparatus. Results demonstrate early significant increases in cardiac output, oxygen uptake, heart rate, rectal temperature, respiratory rate and minute volume, and decreases in mean systemic arterial pressure and total peripheral resistance. Pulmonary vascular resistance remained relatively constant. In conclusion, an early 'hyperdynamic state' has been detected in the baboon during lethal E. coli infusion (similar to that documented in humans with sepsis) characterized by compensatory alterations in cardiovascular hemodynamics, respiration, and metabolism.