(1498) Implementation and Evaluation of Weight-Based Vasopressors in Intensive Care Units

Introduction: Vasopressor infusions are commonly used in critically ill patients to improve mean arterial pressure (MAP) and for the treatment of shock. Vasopressors can be dosed in a weight-based or non weight-based fashion. Currently, there is a paucity of data surrounding which dosing strategy is more effective. We aim to assess whether a weight-based or non weight-based dosing strategy leads to quicker attainment of goal MAP and associated clinical outcomes.

Methods: This retrospective pre-post study was conducted at a single institution. At the study site, vasopressors were historically dosed in a non weight-based fashion. These patients were compared to patients dosed in a weight-based fashion after implementing a new dosing protocol in 2022. We included critically ill adult patients who received vasopressor medications for at least four hours. We excluded patients who were already at their goal MAP at the time of vasopressor initiation and those who were already receiving a vasopressor upon arrival to our institution. The primary outcome was the time to achieve goal MAP. Secondary outcomes included total number of vasoactive agents required, vasopressin use, duration of mechanical ventilation, hospital mortality, and length of stay.

Results: In total, 153 patients were included in the historical non weight-based dosing group and 183 patients were included in the weight-based dosing group. The median time to achieve goal MAP in the non weight-based dosing group was 24 minutes compared to 21 minutes in the weight-based dosing group dosing group (p=0.1713). MAP at 60 minutes also did not differ between groups. There were no differences in any of the secondary outcomes evaluated.

Conclusions: There were no differences in time to achieve goal MAP or in any secondary outcomes. These results suggest that either a weight-based or non weight-based vasopressor dosing approach are appropriate. Limitations include retrospective study design and heterogeneous patient population. We did not evaluate midodrine or push-dose vasopressor use, which are potential confounders. Due to the study design and limitations, our results should be considered exploratory in nature. Future prospective studies could focus on specific patient groups (ie septic shock) and evaluate clinical outcomes.