The intravenous anesthesia process is divided into three phases, induction, maintenance, and recovery phases. The anesthesia is preceded by the establishment of intravenous access, connection to the appropriate monitor, and a rapid pre-surgical assessment. The induction phase is the process of changing the patient from the awake state to the anesthetized state. The maintenance phase is the application of anesthetic drugs during surgery to maintain a certain depth of anesthesia. The recovery period is when all anesthetic medications are discontinued and the patient will gradually regain consciousness, with vital symptoms still being monitored continuously until fully awake. In the case of intubated intravenous general anesthesia patients, the tracheal tube needs to be removed. Intravenous anesthesia in order to play the characteristics of each drug to achieve a smooth anesthesia, light physiological disturbance, less side effects, fast awakening, more to take the composite application, and therefore also known as intravenous composite anesthesia.