Dexmedetomidine

How it works

It stimulates central alpha-2 adrenoceptors to reduce sympathetic outflow and noradrenaline release, producing arousable sedation, analgesia and anxiolysis.

Prescribing in practice

• Dose-dependent bradycardia and hypotension are common and can be profound, so titrate by infusion and avoid bolus loading in haemodynamically unstable patients; transient hypertension may occur with rapid administration.
• Use cautiously in patients with heart block, severe bradycardia or significant ventricular dysfunction.
• Prolonged infusion may be followed by rebound sympathetic activity, so wean rather than stop abruptly.

Monitoring

Monitor continuous heart rate, blood pressure and depth of sedation throughout the infusion.

Counselling the patient

• You will feel drowsy but should remain rousable during sedation.
• Your heart rate and blood pressure will be watched closely.

Evidence & guidelines

Its sedative and perioperative use is supported by its licensed indications and randomised trials demonstrating sedation without significant respiratory depression.