Anaes SAQs · Anaesthetic adjuncts

Noradrenaline — pharmacology and place among vasopressors

Final SAQ — noradrenaline as the sympathetic neurotransmitter and a direct-acting catecholamine; receptor profile of potent alpha-1 plus moderate beta-1 plus presynaptic alpha-2 with NO beta-2, giving a net alpha-dominant effect; haemodynamics of increased SVR and blood pressure with reflex bradycardia and maintained cardiac output (better preserved than phenylephrine because of the beta-1 component); first-line in septic shock because it restores lost vascular tone while maintaining cardiac output and avoids the tachycardia and lactate rise of adrenaline (taught contrast); half-life about 2 to 3 minutes mandating continuous IV infusion at 0.05 to 1.0 micrograms per kg per min via a central line (taught formulary; local protocol governs); adverse effects of peripheral ischaemia and extravasation necrosis treated with phentolamine (Shyu 2025, 0.8%); comparison with adrenaline (no beta-2), phenylephrine (CO maintained vs reduced) and vasopressin (different receptor) (taught); delirium-null in older adults (Dong 2026: no phenylephrine-vs-norepinephrine or ephedrine-vs-norepinephrine difference); airway management in the shocked patient (Ghaffar 2026).