Dexmedetomidine’s Role in Adult ICU After 20 Years of Experience—A Narrative Review

Background: Dexmedetomidine (Dex) is a well-known a2-adrenoceptor agonist with sedative, anxiolytic, sympatholytic, and analgesic effects that has been used principally as adjuvant sedation in the ICU. The enhanced clinical experience of Dex’s use and its physiological effects encourage its application beyond the initial indications. Aim: The purpose of this review is to summarize the current knowledge of Dex’s recently expanded applications in critically ill intensive care unit (ICU) adult patients. Methods: It is a narrative review that critically examines studies published since 2015 and referring to Dex’s use in ICU patients. Results: Despite the preliminary applications and the weak existing recommendation, the unique arousable sedation, in combination with mild opioid-spare analgesic effects, has been confirmed to effectively improve ICU outcomes. Moreover, the anxiolytic and sympatholytic actions have proved to sufficiently enhance sleep quality and prevent and treat ICU delirium and post-ICU syndrome, especially among elderly patients. Recently, increasing evidence advocates for promising neuro-, renal-, and cardio-protective and anti-inflammatory effects of Dex, which are attributed to autophagy and apoptosis inhibition and sympatholytic and ischemia/reperfusion (I/R) injury-protective effects. Conclusions: Beyond sedation, Dex seems to present promising neuroprotective, anti-inflammatory, and immunomodulating effects.