Vasopressor Starting Dose and Association with Hemodynamic Goals, Renal Replacement Therapy, and Mortality

Aim: There are no consensus recommendations for the starting dose of vasopressors in septic shock. The aim of this study was to evaluate the starting dose of vasopressors on hemodynamic, renal, and overall outcomes. Study Design, Materials, Methods: This was a retrospective, single center cohort study from January 2016 to June 2018. The primary outcome of this study was to compare low-dose versus high-dose initial vasopressors and the impact on the attainment of MAP at 6 hours in septic shock patients. We determine groups by evaluating the per-kilogram starting dose of vasopressors (mcg/kg/min) for the entire cohort and divided the cohort into two based on the median starting dose. Low-dose was below the median starting dose and high-dose was above the median starting dose. Bivariate analysis and multivariate linear and logistic regression analysis were completed to evaluate outcomes that were significantly associated with the MAP at 6 hours, development of renal failure needing continuous renal replacement therapy, and mortality. Results: Patients who received high-dose initial vasopressors had a significant higher average MAP at 6 hours (57.9 mmHg vs 51mmHg; P = 0.003) and a lower rate of CRRT requirements (20.7% vs. 51.7%; P = 0.014). Each 0.01 mcg/kg/min increase in starting dose led to a 0.7 mmHg increase in MAP at 6 hours (95% CI 0.037 to 1.175; P = 0.001). Every 0.01 mcg/kg/minute increase in starting vasopressor dose was associated with 1% decreased odds of needing RRT (95% CI 0.0005 to 0.98; P = 0.049). The need for CRRT was significantly associated with mortality (OR=6.1;95% CI 1.23 to 33.3; P = 0.027).