关键词: 右美托咪定, 鼻内给药, 镇静

Abstract: Dexmedetomidine is a highly selective α₂-adrenergic receptor agonist that can cause a mild state of sedation by stimulating α₂ receptors in the locus coeruleus to reduce the release of noradrenaline from nerve cells, but it will not affect a person's consciousness or breathing. The intranasal way has a rich network of capillaries and a large surface area in the nasal mucosa; therefore, after rapid absorption into the blood, it is not degraded by the liver, has an absolute bioavailability of 65%-82%, and reaches a maximum concentration in the plasma in about 38 minutes. Recently, a large number of studies have been conducted in all these areas. Intranasal dexmedetomidine is suitable for the sedation of children in imaging examinations, preoperative anxiolysis and the prevention of emergence delirium under sevoflurane anaesthesia; it has a good overall sedation success rate of around 79.6% and is safer for the respiratory system than traditional oral sedatives. It has shown some good sedative and analgesic effects for older people in reducing preoperative anxiety, fibre-optic bronchoscopy, out-patient procedures, relief of labour pain and burn wound dressing changes. The advantage of the non-invasive way of intranasal delivery is that it is suitable for older people and those with dementia. For the sake of safety, the typical adverse reactions are dose-dependent bradycardia(about 5%)and hypotension(about 8%); most are mild or moderate in severity and can be corrected spontaneously, and the fluctuation in blood pressure is not as severe as that caused by intravenous drugs. In the future, research should be carried out to expand the application range of standardised nasal spray formulations and optimise personalised dosage regimens according to population pharmacokinetic models, as well as to increase the scope of use for these drugs in cases of emergency medical treatment when intravenous access is not available.

Key words: dexmedetomidine, intranasal administration, sedation