Effect of Dexmedetomidine on Postoperative Delirium Inflammasome Activation Inhibition

Delirium is an acute or subacute comorbid syndrome characterized by decreased awareness and cognitive dysfunction accompanied by attention deficit. It varies from 20% to 80%, depending on the report. If delirium occurs in intensive care unit, complications such as intubation tube and catheter removal that are not desired are increased, mechanical ventilation deviation is prolonged, and eventually the intensive care unit is extended. Prevention of delirium is therefore very important, but no medication has been found to prevent delirium.

Recent studies have shown that pro-inflammatory cytokines play an important role in the development of delirium, and as a result of the stimulation of the peripheral inflammatory reaction, proinflammatory cytokines (interleukin (IL) -6, tumor necrosis factor- ), And IL-10) secretion, resulting in the induction of inflammatory responses of the central nervous system. In addition, sleep habits have been shown to affect the pro-inflammatory pathway, and sleep induction and inactivation of the pro-inflammatory pathway may be expected to prevent and treat delirium.

Dexmedetomidine (DEX) is a highly selective a2-agonist with sedative and analgesic effects and reduces sympathetic response to stimuli. Compared to benzodiazepine and opioid, there are fewer side effects of respiratory depression.

In animal studies, the possibility of intrinsic immune suppression of DEX has been demonstrated, and recent studies have shown that intravenous DEX administration reduces IL-6, IL-8, and TNF-a levels, resulting in anti-inflammatory effects. IL-6 plays a key role in neuroinflammation with both proinflammatory cytokines and anti-inflammatory cytokines, including infection, traumatic brain injury, ischemia, and neurodegenerative disorders. DEX plays a key role in IL-6 stimulated IL-6 And inhibits mRNA expression and thus has a brain function-protecting effect. In clinical trials, DEX administration compared with propofol decreased IL-6 secretion and decreased post-operative cognitive impairment in ICU patients after primary surgery. This is closely related to the formation of inflammatory complexes (Inflammasome). In addition, low-dose DEX infusion in patients with ICU at night has a low incidence of delirium during the ICU period, and studies have shown that sleep quality is improved in the DEX group in the mechanical ventilation group. Patients who did not undergo mechanical ventilation also reported improved sleep quality with prophylactic low-dose DEX. As such, the definitive mechanism has not yet been clarified, but the use of low-dose DEX is increasingly proactively used to improve sleep quality.

The purpose of this study was to investigate the effect of DEX on the inflammatory pathway during nighttime after ICU admission and to observe the quality of sleep and the prognosis of delirium.