Case Study, Can Flumazenil Reverse The Effects Of Ropofol?

Kyung-Il Hwang, M.D., Sang-Ho Lee, M.D.

Dept. of Anesthesiology, Wooridul Spine Hospital, Seoul, Korea

The spine surgeons want to know whether spinal roots and cords might have been damaged or not during the percutaneous endoscopic lumbar discectomies (PELDs). Therefore, they must keep asking the patients whether there are any pains or motor weaknesses in legs. Consequently, the anesthesiologists must not let the patients run into the deep sedation during the PELDs, and if patients run into the deep sedation then anesthesiologists have to reverse them from the effects of sedatives immediately.

A neurosurgeon performed a PELD to a 73-year-old male on May 19, 2001. The patient was taking intravenous anesthesia by target-controlled infusion (TCI) using propofol for conscious sedation during the operation. 5 L of oxygen was supplied to him through the nasal cannula. As soon as the operation was begun, TCI of propofol was started at a target plasma level of 1.0 mg/ml adjusted in steps of 0.1 mg/ml to maintain a sedation level 3 on a 5-point sedation scale. However, he was not able to respond to the verbal question of the surgeon in the middle of the operation. At that time, the target plasma concentration was 0.9 mg/ml and the pulse oxygen saturation was 96%. Therefore, the surgeon was incapable of proceeding with the PELD. To awaken the patient, 0.2 mg of flumazenil was injected by intravenous bolus thereafter he returned to the sedation level 1 within one minute. From then on, he could respond to the verbal order of the surgeon. After that event, we found out another patient who came back into the sedation level 1 from deep sedation within one minute after 0.2 mg of flumazenil was injected to him by intravenous bolus during the PELD on June 25, 2001. At that moment, the target plasma concentraion was 1.0 mg/ml and the pulse oxygen saturaion was 97%. He was sixty-eight years old. After all, those operations were carried out properly.

In conclusion, we think that flumazenil antagonized the effects of propofol in two cases although we need further study to define whether flumazenil can reverse the effects of propofol.

References: T Murayama, et al. Br J Anesth 1992;69:61-64