An initially widened pulmonary artery diastolic-pulmonary wedge pressure (PAD-PWP) gradient greater than 5 mm Hg has been reported to be associated with an 83% mortality rate in septic patients. To confirm and extend these observations, we retrospectively reviewed the charts of 47 septic patients. The patients were divided into 2 groups: group 1-12 patients who never had an abnormal gradient during their hospital course, and group 2-35 patients who had an abnormal gradient sometimes during their course. There were no hemodynamic differences. However, the mortality rate in group 2 patients was significantly higher than in group 1 patients (60% vs 25%, p less than 0.01). In patients with an initial gradient, the mortality rate was 61% which is not significantly different than the 83% previously reported. In patients with a persistent or increasing gradient before death or the resolution of sepsis, the mortality rate was 91%. We conclude that although an initial PAD-PWP gradient in patients with sepsis is associated with a high mortality, a much more sensitive indicator is whether the gradient increases or persists over time. There is a 91% mortality in patients with persisting or increasing gradients.