Alpha-2 Adrenoceptor Agonist — Sedative/Analgesic Pregnancy: Avoid — insufficient human data; animal studies show fetal harm; use only for life-threatening ICU indication.

Dexmedetomidine (Burns ICU Sedation)

Brand names: Dexdor, Precedex (US)

Adult dose

Dose: ICU sedation: 0.2–1.4 mcg/kg/hour IV infusion; procedural sedation: 0.5–1 mcg/kg IV loading over 10 minutes then 0.2–1 mcg/kg/hour

Route: IV infusion via syringe pump

Frequency: Continuous infusion (ICU); loading + infusion (procedural)

Max: 1.4 mcg/kg/hour (ICU); duration up to 14 days approved by MHRA

Unique profile: sedation without respiratory depression — patients arousable and co-operative; ideal for burns ICU where neurological assessment is critical and spontaneous breathing preserved. Analgesic-sparing effect — reduces opioid requirements. MHRA 2011 licensed for ICU sedation. Licensed via Dexdor for adults only.

Paediatric dose

Dose: 0.2–0.7 mcg/hour/kg

Route: IV infusion

Frequency: Continuous

Max: 1.4 mcg/kg/hour

Not licensed in paediatrics — off-label use in paediatric burns/ICU under specialist anaesthetic supervision; published paediatric pharmacokinetic data available; BNFc does not include a licensed paediatric dose.

Dose adjustments

Renal

No dose adjustment required — hepatically metabolised. Monitor for accumulation of metabolites in severe renal failure.

Hepatic

Severe hepatic impairment: reduce starting dose (hepatic clearance reduced — accumulation). Start at 0.2 mcg/kg/hour.

Paediatric weight-based calculator

Patient weight (kg)

Clinical pearls

Key advantage in burns: dexmedetomidine provides 'co-operative sedation' — patients respond to verbal commands, can follow instructions during physiotherapy, and can co-operate with respiratory care, while remaining comfortable. Unlike propofol or midazolam which cause respiratory depression and deep sedation
Burns hyperadrenergic state: major burns cause massive catecholamine surge and hypermetabolism (propranolol is used to attenuate this). Dexmedetomidine's alpha-2 agonism provides additional sympatholytic effect — reduces HR, BP peaks, and catecholamine levels, complementing propranolol therapy
MENDS trial and PRODEX trial: dexmedetomidine vs midazolam/propofol in ICU sedation — dexmedetomidine associated with shorter time to extubation, fewer ventilator days, less delirium. PRODEX (2012): dexmedetomidine vs propofol — similar sedation depth, better patient-nurse interaction with dexmedetomidine

Contraindications

Third-degree AV block without pacemaker
Uncontrolled hypotension
Acute cerebrovascular conditions

Side effects

Bradycardia (most common — dose-dependent; may require atropine or glycopyrrolate)
Hypotension (especially loading bolus — use slowly; omit loading dose if haemodynamically compromised)
Dry mouth
Nausea
Agitation on abrupt withdrawal (particularly after prolonged use)
Transient hypertension (during loading bolus — alpha-2 peripheral stimulation before central effect)

Interactions

Beta-blockers (additive bradycardia — caution; propranolol used in burns is particularly relevant)
Anaesthetics and opioids (additive CNS depression — reduce doses of co-administered agents)
Antihypertensives (additive hypotension)

Monitoring

HR (continuous ECG — bradycardia is the main adverse effect; atropine at bedside)
BP (continuous arterial line in ICU burns)
RASS/CPOT sedation score (target RASS 0 to -3 for co-operative sedation)
Respiratory rate and SpO2 (confirm preserved spontaneous breathing)
Temperature (burns hypermetabolism monitoring)

Reference: BNFc; BNF 90; MHRA Approval Dexdor (2011); MENDS Trial (Pandharipande et al. NEJM 2007); PRODEX Trial (Jakob et al. NEJM 2012); British Burns Association ICU Guidelines. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators