Effects of Inotropes on the Mortality in Patients With Septic Shock

Background: Although surviving sepsis campaign guidelines recommend the use of inotropes in the presence of myocardial dysfunction, the effects of inotropes, including epinephrine, dobutamine, and milrinone, on in-hospital mortality in patients with septic shock remains unclear. Materials and Methods: We conducted an international,2-center, retrospective cohort study. The Cox proportional hazards regression model with time-varying covariates was used to investigate whether epinephrine, milrinone, or dobutamine reduces in-hospital mortality in patients with septic shock. Sensitivity analysis was performed using propensity score matching. The primary outcome was in-hospital mortality. The secondary outcome included atrial fibrillation (Afib) with a rapid ventricular response (RVR) in the intensive care unit (ICU) and ICU-free days. Results: A total of 417 patients with septic shock were included, 72 (17.3%) of whom received inotropes. The use of epinephrine and dobutamine was associated with significantly higher in-hospital mortality (epinephrine, hazard ratio [HR]: 4.79, 95% confidence interval [CI]: 2.12-10.82, P =.001; dobutamine, HR: 2.53, 95% CI: 1.30-4.95, P =.046). The effects of epinephrine and dobutamine were time- and dose-dependent. The use of milrinone was not associated with increased mortality (HR: 1.07, 95% CI: 0.42-2.68, P =.345). The use of epinephrine, dobutamine, and milrinone was associated with significantly increased odds of Afib with RVR (epinephrine, odds ratio [OR]: 3.88, 95% CI: 1.11-13.61, P =.034; dobutamine, OR: 3.95, 95% CI: 1.14-13.76; and milrinone, OR: 3.77, 95% CI: 1.05-13.59). On the other hand, the use of epinephrine, dobutamine, and milrinone was not associated with less ICU-free days (epinephrine, adjusted OR: 0.30, 95% CI: 0.09-1.01, P =.053; dobutamine, adjusted OR: 0.91, 95% CI: 0.29-2.84; and milrinone, adjusted OR: 0.60, 95% CI: 0.19-1.87). Conclusion: The present study showed that the use of epinephrine and dobutamine was associated with significantly increased in-hospital mortality in patients with septic shock. These effects were both time- and dose-dependent. On the other hand, the use of milrinone was not associated with increased in-hospital mortality.