(919) Evaluation of Clonidine Utilization for Dexmedetomidine Discontinuation in the Intensive Care Unit

Introduction: Dexmedetomidine is a selective alpha-2 agonist with analgesic and sedative effects commonly used in the intensive care unit (ICU). Clonidine is a centrally-acting alpha-2 agonist available in oral and transdermal formulations that can be used to wean dexmedetomidine and prevent withdrawal. Previous studies evaluating clonidine for this indication are limited to smaller samples of adult or pediatric patients. The aim of this study was to evaluate the safety and efficacy of enteral clonidine in the transition from dexmedetomidine for agitation and sedation in the ICU.

Methods: This was a single-center, retrospective cohort study of adult patients admitted to an ICU at UMass Memorial Medical Center between May 1, 2022 to April 30, 2023 who received enteral clonidine for the indication of weaning dexmedetomidine. The primary outcome was successful discontinuation of dexmedetomidine within 24 hours of starting enteral clonidine. A priori risk factors analyzed included duration of dexmedetomidine prior to clonidine initiation, clonidine total daily dose, average Richmond Agitation-Sedation Scale (RASS) and Sequential Organ Failure Assessment (SOFA) scores, history of a psychiatric disorder, intubation, and use of additional sedation agents at the time of clonidine initiation. Safety outcomes included the incidence of bradycardia, hypotension, and withdrawal symptoms.

Results: There were 73 patients included in the study. The median total daily dose of clonidine at initiation was 0.4 mg. The primary outcome of dexmedetomidine discontinuation within 24 hours occurred in 38 patients (52%). Analysis of the a priori risk factors indicated that intubation (63% failure vs. 24% success, p=0.0009) and use of additional sedation agents (51% vs. 24%, p=0.02) were associated with failure to wean dexmedetomidine within 24 hours of clonidine initiation. Incidences of bradycardia (5% clonidine vs. 16% dexmedetomidine, p=0.04) and withdrawal (0% vs. 49%, p < 0.0001) were higher while patients were on dexmedetomidine monotherapy.

Conclusions: The results indicate that clonidine is efficacious for discontinuation of dexmedetomidine with lower rates of adverse effects. Further studies are needed to evaluate the optimal dosing of clonidine and identify patient populations that would benefit most from this intervention.