Oral analgesic sedation of mentally handicapped patients - preliminary results

Objective:
Patients who are uncooperative because of mental retardation present a challenge for the medical personnel. Intravenous or intramuscular administration of drugs is often difficult without restraint so the oral route seems to be the best option. The aim was to develop oral premedication for handling uncooperative adult patients in a dental care model.

Design:
Prospective randomised single blinded clinical study.
Setting:
A stomatology department of a research institute.

Material and methods:
After ethics committee approval and trustees' consent, a flavoured drink with midazolam 0.3 mg . kg^-1 + clonidine 2 µg . kg^-1 + ketamine 5 mg . kg^-1 (Group Clo) or midazolam 0.3 mg . kg^-1 + ketamine 5 mg . kg^-1 (Group K) was offered to mentally handicapped patients scheduled for dental examination. The measured parameters included the onset of sedation enabling positioning the patient in the dental chair and securing venous access, vital signs (non-invasive blood pressure, pulse, SpO₂) and psychomotor recovery. All monitoring was non-invasive.

Results:
So far 17 patients in the Clo group and 8 patients in the K group have been included in the study. There were no differences in the demography and duration of treatment. All patients accepted the drink. Median time of the first signs of sedation was 10 minutes in the Clo group and 7 minutes in the K group, median onset time of full effect was 20 min in both groups. The level of sedation enabled stress-free peripheral vein cannulation in all patients and in 18 of 20 patients also dental treatment under local anaesthesia. Fractional administration of etomidate or propofol and/or ketamine was necessary in 2 patients. There was one case of deep sedation resulting in transitory loss of airway patency in each group and 3 cases of tachycardia in the K group vs. none in the Clo group (p < 0.05). Spontaneous recovery occurred at 105 min. in the Clo group and at 60 min. in the K group (median). Flumazenil IV was used in the remaining 8 patients in the Clo group and 3 in the K group. The onset of flumazenil effect was 1-2 min. There were 2 cases of resedation after flumazenil in the Clo group vs. 0 in the K group.

Conclusion:
Preliminary results indicate that oral premedication with clonidine, ketamine and midazolam combination produces good quality sedation and better cardiovascular stability compared to sedation without clonidine.

Keywords: mental incapacity; oral premedication; analgesic sedation; ketamine; midazolam; clonidine; stomatology