Ketamine has been used in clinic as an intravenous anesthetic with little cardiovascular or respiratory depression for several decades.The major problem with ketamine is that it produces psychotomimetic effects that may be associated with postoperative dysphoria.It has also been demonstrated that ketamine possesses analgesic properties in a subanesthetic doses.Small-dose ketamine in combination with sedative drugs has been used for sedation and analgesia with less toxicity than either drug alone.The purpose of this article is to review the clinical application of small-dose ketamine in induction of general anesthesia,short-term operation,and analgesia.
