??? ?????? dexmedetomidine? ??? ??? ??

摘要

Many sedatives are used clinically and include benzodiazepines, barbiturates, antihistamines, propofol, and alpha-2-agonist. Benzodiazepines activate GABA neuronal receptors in the brain and present sedating, hypnotic, anxiolytic, amnestic, and anticonvulsant effects, but low analgesic effects. Propofol induce sedative, anxiolytic, and amnestic effects but no analgesic effects. However, risks such as cardiopulmonary instability and hypotension must be considered during administration. Dexmedetomidine is a high selective alpha-2 agonist and has many advantages as a sedative. Patients under dexmedetomidine sedation awaken easily and are more likely to be cooperative. Risk of respiratory depression and cardiopulmonary instability is low as well. Additionally, dexmedetomidine decreases amount of analgesic needed during and after surgery, presenting analgesic effects. Dexmedetomidine also decreases risk of delirium. However, bradycardia may occur and biphasic effects on blood pressure may be observed during beginning of administration. Because of lengthy symptom onset and offset time, physicians should carefully control administration at the beginning and end of dexmedetomidine administration. The purpose of this review is to evaluate the efficacy and availability of dexmedetomidine in various clinical fields including sedation for critically ill patients, regional anesthesia, monitored anesthesia care for some invasive procedures, stabilization of heart in cardiac surgery or endoscopic procedures.