Angiotensin II vs. Vasopressin in Septic Shock

Sepsis affects \>1 million Americans yearly and, when septic shock ensues, is associated with high morbidity and mortality. Though first-line norepinephrine is standard of care, there are limited prospective data to guide the choice of additional vasopressors in septic shock. While more studies are needed, preliminary data suggest that the vasopressor angiotensin II (AngII) may improve outcomes in septic shock.

This study is a pilot randomized controlled trial (RCT) comparing AngII (intervention) and vasopressin (standard of care) as second-line vasopressors in septic shock. The goal is to demonstrate feasibility of a large multicenter RCT and eventually to demonstrate that AngII use improves important endpoints (e.g., mortality, need for organ support) in all or certain subsets of patients with septic shock.

Furthermore, there are no biomarkers currently available and validated to guide the choice of vasopressor therapy in septic shock. In this study the investigators will investigate serum renin as such a biomarker. Renin has been shown in preliminary studies to accurately predict mortality in septic shock, outperforming lactate, and to predict beneficial response to AngII. The investigators aim to validate the use of renin as a biomarker in septic shock and prove its utility in guiding vasopressor selection, with the goal of incorporating renin levels at specified time points and/or change in renin levels into an algorithm used to select patients for AngII therapy in the subsequent large multicenter RCT.