First-Line Vasopressor Use in Septic Shock and Route of Administration: An Epidemiologic Study.

Rationale: Norepinephrine is a first-line agent for the treatment of hypotension in septic shock. However, its frequency of use and potential barriers to its use are unclear.

Objectives

To evaluate the frequency of use of norepinephrine in septic shock, to identify potential barriers to its use, and to evaluate trends in use of vasopressors over time.

Methods

We conducted a retrospective population-based cohort study of patients with septic shock in Alberta, Canada, between July 1, 2012, and December 31, 2018. The primary outcome was receipt of a first-line vasopressor other than norepinephrine ("nonnorepinephrine vasopressor"). Predictors of receiving a nonnorepinephrine vasopressor were assessed using a multivariable-adjusted, multilevel logistic regression model with intensive care unit as a random effect.

Results

Among 6,343 patients with septic shock, the proportion of patients receiving nonnorepinephrine vasopressors as first-line treatment decreased steadily from 11.5% in 2012 to 3.0% in 2018. Two factors most strongly associated with their receipt were having peripheral intravenous access only (adjusted odds ratio [aOR], 6.15; 95% confidence interval [CI], 4.58-8.26; P < 0.001) and year of admission (aOR, 0.74 per year after 2012; 95% CI, 0.69-0.80; P < 0.001). Other factors that had associations after adjustment included admission to a nonteaching hospital (aOR, 2.19; 95% CI, 1.23-3.89; P = 0.007), admission to a coronary care unit (aOR, 2.56; 95% CI, 1.001-6.54; P = 0.05), Sequential Organ Failure Assessment score (aOR, 0.92 per unit increase; 95% CI, 0.88-0.96; P < 0.001), and heart rate (aOR, 0.92 per 10-beat per minute increase; 95% CI, 0.87-0.97; P = 0.002).

Conclusions

In a large cohort of patients in Alberta, Canada, we found a steady decrease in use of first-line vasopressors other than norepinephrine in septic shock. The strongest factor associated with their use was the presence of only peripheral venous access, suggesting that this may still be considered a barrier to administration of norepinephrine.