The impact of push-dose phenylephrine use on subsequent preload expansion in the ED setting.

Background: The utilization of bolus-dose phenylephrine (PHE) has transitioned to the emergency department (ED) for the treatment of acutely hypotensive patients, despite a paucity of literature in this setting.

Methods: This was a single center retrospective chart review of the utilization of bolus-dosed PHE for acute hypotension in the ED at an academic non-forprofit hospital. The primary objective of this study is to report the frequency of patients that were initiated on a continuous vasopressor infusion (CVI) within 30 minutes after the first administration of bolus-dose PHE. Secondary objectives included an observational description of the impact of early preload expansion (fluids) on the initiation of CVIs in the setting of bolus-dose PHE in the ED.

Results: Seventy-three patients met inclusion criteria for analysis. The primary outcome, 46.5% (n = 34) of patients were initiated on a CVI within 30 minutes following bolus-dose PHE. Initial preload expansion (30 mL/kg of IV fluids) was found to be significantly disproportionate with 34.2% appropriately fluid challenged vs 65.8% (P = .0048). In addition, a significant decrease in the number of PHE bolus doses were required [1.5 vs 2.3 (P = .01)] in the adequately IVF challenged group. For secondary endpoints, PHE was most commonly indicated for peri-intubation hypotension (n = 52, 71.2%). Significant adverse events were documented for 15 (20.5%) patients, with bradycardia (n = 7; 9.6%) as the most common adverse event.

Conclusions: Initial preload IVF expansion was found to be significantly disproportionate, and appears to be associated with an increase number of phenylephrine bolus doses in our study population.