We analyzed the relationship of increases in oxygen delivery to changes in oxygen consumption in ten patients with hyperdynamic septic shock. Increases in oxygen delivery from 413 ± 14 (SEM) to 535 ± 19 ml/min-m2(p< .01) were associated with increases in oxygen consumption from 136 ± 10 to 161 ± 5 ml/min-m2(p< .05). Arterial lactate decreased from 4.6 ± 1.6 to 2.1 ± 0.3 mmol/L (p< .05). These observations suggest that oxygen utilization is perfusion-limited in hyperdynamic septic shock.