Dexmedetomidine — sedation without respiratory depression

Dex use + dose + caveats

Mnemonic device

α2 → sympatholysis

Mapping

MoA

α2-adrenergic agonist — pre-synaptic; reduces NE release; sedation + analgesia + sympatholysis WITHOUT respiratory depression

Dose

Load 1 mcg/kg over 10 min (often skipped — drops BP); maintenance 0.2-0.7 mcg/kg/hr

Use

ICU sedation, awake fiberoptic, bronchoscopy, MRI sedation peds, post-op shivering, emergence delirium prevention

Watch

Hypotension + bradycardia (sympatholysis); blunted stress response (less catechol release with intubation/extubation — could be good or bad); slow onset/offset

Reversal

Atipamezole (off-label in humans; veterinary use); supportive care + atropine for severe brady

Clinical note: Dex is the go-to for awake fiberoptic intubation — patient stays cooperative + breathing + arouseable. Pediatric MRI sedation popular alternative to propofol. Avoid in heart block + cardiogenic shock.