Evaluating the Effect of Guanfacine on Dexmedetomidine Duration in Critically Ill Patients

Introduction: Current guidelines for management of agitation/sedation in adult intensive care unit (ICU) patients recommend dexmedetomidine (DEX) as a preferred agent for light sedation in critically ill, ventilated patients. However, prolonged administration of DEX may lead to withdrawal upon cessation. Guanfacine, an alpha-2-adrenergic agonist, is used off-label to facilitate DEX weaning or discontinuation. Limited studies exist regarding the efficacy and safety of guanfacine for this use. This study aims to evaluate whether guanfacine reduced the total duration of DEX therapy in comparison to patients who were on DEX alone.


Methods: This retrospective, single-center cohort study included adult patients admitted to an ICU and received DEX alone or in combination with guanfacine for a minimum of 24 hrs from January 2023 to October 2023. The primary outcome was the total duration of DEX therapy. Secondary outcomes included improvements in the Intensive Care Delirium Screening Checklist (ICDSC) score (evaluated 24 hrs pre- and 72 hrs post- guanfacine initiation), hospital and ICU length of stay (LOS), and incidence of adverse events.


Results: A total of 120 patients were included, with 60 patients in each group. The mean duration of DEX therapy was significantly longer in the guanfacine group compared to the DEX only group (189 hrs vs 81 hrs, respectively; p< 0.00001). At DEX discontinuation the mean dose of guanfacine was 2.2 mg. DEX was restarted less frequently in the DEX only group (5%) compared to the guanfacine group (11.7%; p=0.32). Mean hospital LOS was 37 days in the guanfacine group versus 31 days in the DEX only group (p=0.07), while ICU LOS averaged 21 days versus 14 days, respectively (p=0.001). The incidence of hypotension was lower in the guanfacine group (47%) than the DEX only group (68%; p=0.02). Bradycardia occurred in 5% of patients in both groups (p=1). Among patients with pre- and post- ICDSC scores, improvement was observed in 55% of the guanfacine group versus 48% of the DEX only group (p=0.55).


Conclusions: Our study found that patients who received guanfacine with DEX had statistically significant longer durations of DEX therapy and ICU LOS compared to those who received DEX alone. Further prospective studies are warranted to define guanfacine’s role in sedative weaning.