Effect of bacteremia and fluid resuscitation on cardiac output

The cardiac output acutely inducible by a 1-ml/kg/min saline infusion was observed in 12 septic and 7 nonseptic cynomolgus monkeys. In septic monkeys intravenous live E. coli were titrated to rapidly produce equivalent hypotension which was maintained for 1 hr before saline. Bacteria dose range was 1.3 X 10(11) bacteria/kg-400 X 10(11) bacteria/kg. There was no significant correlation between the dose of bacteria and the cardiac output nadir; however, the subsequent maximum cardiac output during saline resuscitation was significantly negatively correlated with the bacterial dose. In conclusion, widely varying amounts of intravenous bacteria can produce the same degree of hypotension and not correlate with cardiac output. In contrast, cardiac output measured early during subsequent saline resuscitation better predicts the severity of bacteremia.