(1641) Evaluating the Safety of Vasopressor Discontinuation Strategies in Patients With Septic Shock

Introduction: The 2021 Surviving Sepsis Guidelines recommend which vasopressor to initiate first, however, there is a paucity of data to guide the order of vasopressor discontinuation. The purpose of this analysis was to evaluate the incidence of rebound hypotension in patients with septic shock based on order of norepinephrine or vasopressin discontinuation.

Methods: This was a single-center, retrospective analysis of adult patients with septic shock admitted to an intensive care unit (ICU) who had either vasopressin (AVP1) or norepinephrine (NE1) discontinued first between January 1, 2021 and December 31, 2021.The major outcome was incidence of hypotension within six hours of first discontinued agent, defined as re-initiation of vasopressors, administration of fluid bolus ≥ 500mL, two consecutive mean arterial pressure readings < 65mmHg, or up-titration of remaining vasopressor. A multivariable regression analysis was performed to identify independent predictors of developing hypotension. A Kaplan-Meier curve evaluated time to hypotension. Notable minor outcomes included incidence of hypotension within 12 and 24 hours, ICU length of stay (LOS), ICU mortality, and time to shock resolution.

Results: During the study period, 580 patients were evaluated for inclusion, of which 209 were included: 150 in the NE1 group and 59 in the AVP1 group. There was no difference in incidence of hypotension at six (55.3% vs 66.1%), 12 (14.7% vs 5.1%), or 24 (6.7% vs 15.3%) hours, ICU LOS, ICU mortality, and shock resolution between NE1 and AVP1 groups. When controlling for confounders, no variables were independently associated with the development of hypotension; however, there was a trend toward increased risk in the AVP1 group (p = 0.1) and patients on steroids at baseline (p = 0.1). The Kaplan-Meier curve showed the AVP1 group had a significantly quicker time to hypotension than the NE1 group (p = 0.04).

Conclusions: This analysis suggests there is no difference in rebound hypotension within six hours regardless of vasopressor discontinuation order. A shorter time to hypotension may be seen if vasopressin is discontinued prior to norepinephrine. Further studies are warranted to elucidate the impact of vasopressor discontinuation order and establish potential weaning strategies.