Objective: A combination of midazolam-clonidine-ketamine was evaluated in terms of their influence on haemodynamic and respiratory parameters in dental surgical patients Design: Non-comparative clinical study. Setting: Centre of Experimental Medicine, Prague, Department of Anaesthesiology and Resuscitation IKEM, Department Anaesthesiology and Intensive Medicine – IKEM). Materials and methods: In 30 patients of both genders intravenous midazolam was administered in a total dose of 3 mg.We recorded changes in haemodynamic and respiratory parameters caused by midazolam.After 2 minutes we added clonidine, 50 µg iv, and investigated changes in haemodynamics and respiration. After the next 2 minutes racemic ketamine was administered, 20 mg iv.We maintained on verbal contact with the patient. Afterwards the dentist injected local anaesthetics (articain). To make sedation moreeffective,weadded midazolamin 1mg iv boluses.To enhancethe analgetic effectwe added ketamine, 10 mg iv. To find out the frequency of anterograde amnesia we showed the patients photographs of objects of daily use.We evaluated the rate of psychomotor recovery and the occurrence of side effects. Results: Conscious sedation with a combination of midazolam-clonidine-ketamine was used in a group of patients undergoing multiple tooth extractions or extraction of an impacted wisdom tooth. Patients were able to cooperate during the procedure. Haemodynamic parameters and haemoglobin oxygen saturation were affected non-significantly. Midazolam and clonidine completely reversed the cardiovascular and psychomimetic effects of ketamine. There was complete anterograde amnesia of the procedure. Within 60–90 minutes after the procedure, patients were able to be escorted at home by adults. The incidence of side effects was minimal. Conclusion: Treatment with midazolam-clonidine-ketamine further expands the range of drugs available for pharmaco-therapy. In future, racemic ketamine will be replaced by its isomer, while clonidine will be replaced by highly specific dexmedetomidine with beneficial pharmacokinetic parameters.

        Key words: midazolam – clonidine – ketamine - balanced conscious sedation technique – dental surgery