Timing of Vasopressin Addition to Norepinephrine and Efficacy Outcomes in Patients With Septic Shock

Current guidelines recommend norepinephrine as the first-line vasopressor in septic shock followed by addition of vasopressin to achieve a goal mean arterial pressure. Limited evidence exists evaluating how the timing of vasopressin addition affects clinical outcomes in septic shock.

The objective of this study was to determine whether the timing of the addition of vasopressin to norepinephrine affects shock resolution.

This was a multi-site, single system, retrospective cohort, institutional review board (IRB)-approved study examining adult patients with septic shock who received norepinephrine and vasopressin. Patients were divided and statistically analyzed in two subgroups: early vasopressin addition (<3 hours) and late vasopressin addition (≥3 hours). The primary outcome was time to shock resolution, defined as vasopressor free for at least 24 hours. Secondary outcomes included norepinephrine dose at 3 hours after initiation of vasopressin, in-hospital mortality, and intensive care unit length of stay.

A total of 243 patients were included in this study. A statistically significant decrease in time to shock resolution was observed in the early vasopressin addition group compared to the late vasopressin addition group (37.6 hours vs 60.7 hours; adjusted hazard ratio [HR]: 2.07 [1.48-2.89; P = <0.001]). The early addition of vasopressin did not affect norepinephrine dose or in-hospital mortality but did lead to a decreased intensive care unit (ICU) length of stay (4.3 days vs 5.3 days, P = 0.02).

Addition of vasopressin to norepinephrine within 3 hours was associated with a faster time to shock resolution. These findings suggest a potential for improved clinical outcomes with earlier vasopressin addition.