Dexmedetomidine: A Review of Its Use for the Treatment and Prevention of Hyperactive Delirium in Intensive Care Units (ICU)

Introduction The incidence of delirium in the ICU occurs upwards of 80% and is associated with increased length of stay in hospitals and mortality. The effects of previously recommended antipsychotics and benzodiazepines for management of ICU delirium have come into question as they have been associated with no change in or even exacerbation of delirium. This has led to unclear pharmacological treatment recommendations and the need to seek explicit treatment of ICU delirium. Dexmedetomidine, an adrenergic alpha 2 receptor agonist, has been shown to reduce the development of delirium and improve the resolution of delirium. The aim of this review is to explore the evidence that supports the use of dexmedetomidine for treatment and prevention of hyperactive delirium in ICU patients. Methods A literature review using articles from databases such as PubMed and Google Scholar was conducted to gather supporting evidence on the use of dexmedetomidine in ICU delirium. The articles included in this review were randomized controlled trials (RCT), observational studies, systematic reviews and meta-analyses, and literature review articles. The main outcomes measured included a decrease in scales used to measure delirium and agitation, time spent in delirium, duration of mechanical ventilation, and incidence of delirium. Results A RCT comparing the use of lorazepam and dexmedetomidine in 106 adult mechanically ventilated ICU patients demonstrated that dexmedetomidine at 0.15- 1.5 μg/kg/h resulted in more days without delirium. Another study done to compare the efficacy and safety of prolonged sedation in 375 mechanically ventilated patients found that individuals receiving dexmedetomidine at a rate of 0.2-1.4 μg/kg/h spent less time on the ventilator, developed delirium 20% less often, and were off mechanical ventilation almost 2 days sooner compared to midazolam. The Dexmedetomidine to Lessen ICU Agitation RCT, which involved 74 adults treated at rate of 0.5-1.5 μg/kg/h in whom extubation was not done due to delirium severity, demonstrated that dexmedetomidine increased ventilator free hours by 17 hours compared to placebo. Another RCT of 100 delirium-free ICU adults demonstrated a greater proportion of patients who remained delirium-free during the ICU stay after administration of nocturnal dexmedetomidine at rate of 0.2-0.7 μg/kg/h. A case series done to explore the use of dexmedetomidine in post-traumatic brain injury (TBI) showed dexmedetomidine at a rate of 0.49 μg/kg/h in 85 patients with severe TBI did not worsen neurological function. Conclusion Delirium in ICU patients occur at exceptionally high rates and there is a need for clear pharmacologic treatment. Current literature supports the use of dexmedetomidine for reduction of delirium in ICU patients with potential to eliminate risk associated with previously used antipsychotics and benefits of safe use in TBI, decreased risk of polypharmacy and overall mortality associated with ICU delirium. Funding No Funding