Inotrope selection in mixed cardiogenic shock with sepsis: a comparative analysis between milrinone and dobutamine

Despite increasing recognition of mixed cardiogenic shock-particularly in patients with concomitant sepsis-there remains limited guidance on optimal inotropic selection, and the comparative effectiveness of different inotropes in this population is unclear.

To examine the association between inotrope selection and in-hospital outcomes, including all-cause mortality, among patients with cardiogenic shock and sepsis.

Using the PINC AI enhanced-claims database (2016-2022), we identified patients with cardiogenic shock and sepsis using International Classification of Diseases, Tenth Revision codes (ICD-10) that were present on hospital admission and a pharmacy charge code for dobutamine or milrinone within 2 days of hospitalization. The primary outcome was all-cause hospital mortality. Secondary outcomes included inotrope duration, in-hospital length of stay, atrial arrhythmia, initiation of renal replacement therapy, use of mechanical circulatory support devices, and heart transplantation. We used greedy nearest neighbor matching on the propensity score (dobutamine vs milrinone) followed by g-computation to estimate effects of inotrope selection on outcomes. We examined heterogeneity of treatment effect in patients with renal disease, congestive heart failure, pulmonary circulatory diseases, and on epinephrine prior to inotrope initiation.

Out of 10 447 included patients, 74.4% received dobutamine and 25.6% received milrinone. Postmatching characteristics between the milrinone and dobutamine groups were similar (all standardized mean differences <0.1). The primary outcome all-cause mortality was similar between the postmatched milrinone and dobutamine groups (41.6% vs 42.7%; risk difference, -1.4% [95% CI, -3.7% to 1.5%]; P = .40). Patients initiated on milrinone (vs dobutamine) had longer inotrope durations (5.1 vs 3.5 days; mean difference, 1.7 [95% CI, 1.4-1.9] days; P < .001), longer in-hospital length of stay (10.0 vs 9.1 days; mean difference, 0.9 [95% CI, 0.4-1.3] days; P < .001), and more usage of anti-arrhythmic agents (56.0% vs 44.5%; mean difference, 11.5% [95% CI, 8.9%-14.1%]; P < .001). We did not observe any heterogeneity of treatment effect for all-cause mortality based on the preexisting conditions of interest.

Using a large, multicenter cohort, we identified no differences in all-cause mortality between dobutamine and milrinone among patients with concurrent cardiogenic shock and sepsis overall. However, secondary outcomes favored dobutamine.