Sequential cardiorespiratory patterns associated with outcome in septic shock.

Sequential hemodynamic and oxygen transport monitoring was performed in 33 patients with septic shock to define physiologic patterns associated with outcome. Measurements taken over a 24-hour period prior to the hypotensive crisis, defined as the lowest initial mean arterial pressure (MAP) after a decrease of at least 30 mm Hg from initial normal values, were compared to those taken during the 24 hours thereafter. In the 24-hour period prior to the hypotensive crisis, the 19 survivors demonstrated significantly greater cardiac index (CI), left cardiac work index (LCWI), oxygen delivery (DO2), and oxygen consumption (VO2) than the 14 patients who died. No other significant differences were found between the two patient groups. When sequential cardiorespiratory patterns were examined, significant increases in CI, LCWI, left ventricular stroke work index (LVSWI), DO2, and VO2 were present in survivors as early as eight hours before the hypotensive crisis. The results presented in this study suggest that patterns of survival may be determined in critically-ill septic patients before shock, as defined by the initial hypotensive episode, develops.