Tissue hypoxia resulting from regional blood flow abnormalities and oxygen extraction defects may underlie the pathogenesis of multiple system organ failure (MSOF) in sepsis. Low-dose dopamine (LDD) is widely employed to enhance splanchnic perfusion although data to support this approach are lacking. We assessed the effect of LDD on surrogate markers of renal and gastric perfusion. Sixteen nonoliguric mechanically ventilated patients with sepsis syndrome received LDD (3 micrograms/kg/min) or placebo in a double-blind crossover design experiment. Hemodynamics, gastric intramucosal pH (pHi) urine volumes, urinary sodium excretion, and cimetidine-corrected creatinine clearance were compared. Mortality for the group was 63%. LDD caused a significant increase in urine volume (88 +/- 58 to 115 +/- 70 ml/h, p = 0.02, 95% confidence interval for change 4.7 to 49 ml/h), but no significant change in any other parameter. We conclude that use of LDD results in diuresis but does not improve other markers of renal or gut perfusion. These data do not support the use of LDD to reduce risk of progression to MSOF in sepsis.