Vasopressin for Septic Shock in a Medical-Surgical Intensive Care Unit

Critically ill patients often need vasopressors to treat hypotension related to septic shock and to maintain adequate systemic perfusion. Although the 2017 guidelines of the Surviving Sepsis Campaign recommend norepinephrine as first-line therapy, they also state that vasopressin may be considered as an adjunctive agent for patients with refractory shock. Limited evidence is available for directing optimal administration of vasopressin. As such, prescribing practices are not standardized and may vary according to the particular clinician, the clinical scenario, and various patient-specific factors.

To review the current practice of administering concomitant norepinephrine and vasopressin therapy to patients with septic shock, to describe variability in vasopressin administration, and to evaluate effects on patient safety in a medical-surgical intensive care unit (ICU).

This single-centre retrospective chart review involved 100 adult patients admitted to the ICU who received vasopressin and norepinephrine for septic shock between April and December 2017. The data were analyzed with descriptive statistics.

The mean time to initiation of vasopressin was 12.0 (standard deviation [SD] 21.6) h after initiation of norepinephrine. The mean dose of norepinephrine at the time of vasopressin initiation was 29.5 (SD 19.7) μg/min. The mean vasopressin dose prescribed was 0.04 (SD 0.03) units/min, with a range of tapering and discontinuation regimens. The mean duration of vasopressin therapy was 49.1 (SD 65.2) h, and vasopressin was discontinued before norepinephrine in 49 of the patients. A total of 60 hypotensive events occurred after vasopressor discontinuation and were more common when vasopressin was discontinued before norepinephrine.

Vasopressin dosing was comparable to that reported elsewhere; however, discontinuation practices were inconsistent. These results show that variability in the literature supporting vasopressin use has led to variability in vasopressin administration and discontinuation practices; however, correlation with improvement in clinical outcomes, such as mortality or ICU length of stay, is unclear, and further research is required to determine the ideal approach to vasopressin use.