Timing of vasopressin initiation in septic shock

Vasopressin is often used as a second line agent to Noradrenaline in septic shock. The usual approach to sepsis is commencement of fluids and if a mean arterial pressure (MAP) >65, is not achieved rapidly,  to commence Noradrenaline. If unable to reach the target MAP, a second agent, usually Vasopressin, is added. The evidence for this is weak. (15 minute read)

This study looked at outcomes related to the timing of vasopressin initial (1). Guidelines recommend commencing Vasopressin when the dose of Noradrenaline is in the range of 0.25-0.5mcg/kg/min(2).

Is there an effect on patient outcomes, if we reach higher Noradrenaline doses, before Vasopressin is commenced? It may result in a delay in achieving an appropriate MAP, resulting in a worst prognosis.(3)

The Question this paper aimed to answer
“We hypothesized that vasopressin initiation is associated with lower mortality when adults with septic shock are treated with low doses of NE.”