686: THERAPEUTIC THRESHOLDS OF DEXMEDETOMIDINE IN THE DEVELOPMENT OF ICU DELIRIUM

Abstract

Introduction: The use of dexmedetomidine is increasing as a sedation agent in the pediatric population. The aim of this study is to determine if there is a dose-dependent relationship between dexmedetomidine and the development of ICU delirium in the pediatric cardiac intensive care unit (PCICU). We sought to describe a relationship between both the cumulative dose and the average continuous dose of dexmedetomidine with ICU delirium in patients admitted to a PCICU. Methods: This is a single-center, retrospective chart review of patients age 0-21 years admitted to the PCICU for more than 24 hours, who had delirium assessments performed using the Cornell Assessment of Pediatric Delirium (CAPD). CAPD scores were collected. Exposures prior to each CAPD score were collected in 12-hour time intervals. The primary outcome was cumulative dose exposure of dexmedetomidine in micrograms per kilogram over the course of each admission. Cumulative dosing was obtained by accounting for the amount of both the continuous infusions and intermittent bolus received over the entire admission. Average dose exposure in micrograms/kilogram/hour was also obtained over each twelve-hour time period before the next CAPD score was recorded. Descriptive statistics was used to characterize the cohort and report dosing outcomes. Results: Two-hundred and seventy-seven patients were included in the analysis, which accounted for a total of 5,031 CAPD assessments. Increased length of stay, use of invasive mechanical ventilation, and exposure to dexmedetomidine, benzodiazepines, or opiates, were independently associated with delirium. Patients with delirium received a higher cumulative dose of dexmedetomidine (0.81 microgram/kilogram vs 15.01 micrograms/kilogram, p = 0.003). Additionally, patients with delirium, on average, received a higher continuous infusion dose of dexmedetomidine (0.23 micrograms/kilogram/hour vs 0.54 micrograms/kilogram/hour, p < 0.001). Conclusions: Patients with delirium in the PCICU had a higher cumulative dose of dexmedetomidine and higher average dose of a continuous infusion of dexmedetomidine. Future initiatives and studies examining institutional protocols for sedation in this population should incorporate considerations for their impact on the development of ICU delirium.