The influence of clonidine on oral ketamine-midazolam premedication in intellectually disabled patients indicated for dental procedures: double-blind comparison of two sedation regimes.

BACKGROUND: Dental procedures on intellectually disabled patients represent a clinical challenge. The oral administration of sedating drugs can remediate the problems with cooperation and enable the medical procedures to take place. Standard guidelines are lacking for oral sedation of the intellectually disabled.

OBJECTIVE: To compare two oral combinations of sedating drugs in terms of time to the onset and achievement of full sedation, vital signs, behavioral measures and safety.

METHODS: In a group of 29 intellectually disabled patients we compared two oral combinations for analgosedation: ketamine (5 mg/kg) - clonidine 2 µg/kg - midazolam 0.3 mg/kg (N=17) or ketamine 5 mg/kg - midazolam 0.3 mg/kg (N= 12 patients). Drugs were dissolved in a sweet drink.

RESULTS: Full sedation was achieved within 25 min. in 27 patients and serious side effects were not detected. Clonidine in combination with ketamine and midazolam did not exert any significant effect by means of the onset of sedation, time to the achievement of full sedation, vital signs and behavioral measures of sedation (Vancouver Interaction and Calmness Scale) and agitation (Pittsburgh Agitation Scale).

CONCLUSIONS: Our study is the first to document that oral administration of ketamine and midazolam in low doses represents a safe and effective method of premedication in intellectually disabled patients indicated for dental procedures. Clonidine co-administration did not exert any substantial benefit and should be left out in this clinical setting.