Objective: To assess the relative contributions of changes in vascular tone and changes in cardiac function to hemodynamic recovery from septic shock.
Design: Case series, observational study.
Setting: Multidisciplinary department of intensive care in an academic hospital.
Patients: Sixty-seven patients with septic shock (prolonged hypotension, signs of tissue hypoperfusion, signs of sepsis, suspected source of infection, or documented bacteremia). In addition to the antibiotic therapy and the removal of the source of sepsis whenever possible, each patient received intravenous fluids and vasoactive agents (dopamine, norepinephrine, and dobutamine). Each patient was also treated with mechanical ventilation. Twenty-four (36%) patients survived their intensive care unit course.
Interventions: Hemodynamic measurements were obtained at baseline, after initial resuscitation (as soon as apparent hemodynamic stability was achieved), after 12 hrs, and after 24 hrs.
Measurements and main results: There were no significant differences in hemodynamic or oxygen-derived variables at baseline between the survivors and the nonsurvivors. During the initial resuscitation period, only the survivors demonstrated a significant increase in mean arterial pressure (from 69 +/- 17 to 82 +/- 18 mm Hg; p < .02) and left ventricular stroke work index (from 25.2 +/- 11.0 to 35.5 +/- 19.4 g.m/m2; p < .05). The increases in cardiac index and systemic vascular resistance were greater in the survivors than in the non-survivors, but the differences did not reach statistical significance. Study of the left ventricular function curves indicated an improvement of left ventricular function in the survivors but not in the nonsurvivors.
Conclusion: An early improvement in left ventricular function is a hallmark of the survivors from septic shock.