Objective: Evaluation of a sedation technique which involved titrating intravenous midazolam to an 'ideal' sedation end point, followed by a continuous infusion of propofol. This technique might be a satisfactory alternative to general anaesthesia for implant surgery in anxious patients or when procedures exceed 60-min duration.
Material and methods: 20 patients were treated on 23 occasions. A 2-mg bolus of midazolam was injected intravenously followed after 90 s by 1 mg increments until the patient was adequately sedated. 30 min after this induction with midazolam, a propofol infusion was started at a rate which varied between 0-300 mg/h (0-30 ml/h). The actual infusion rate was adjusted in order to maintain the optimum sedation level which had been achieved using midazolam. The quality of sedation was assessed using Ellis and Sedation scores.
Results: Midazolam dosage varied between 5 and 14 mg. The initial propofol infusion rate was 200 mg/h (20 ml/h) for 21 of the 23 implant surgery treatments.
Conclusion: The sedation technique described takes advantage of the differing pharmacokinetic properties of midazolam and propofol. Initial sedation was achieved using midazolam, this was then maintained using a variable propofol infusion. The shorter distribution and elimination half-lifes of the latter drug made matching the level of sedation to the patient's needs easier and also provided good short-term recovery.