Anaes Vivas · Anaesthetic adjuncts

Data viva — vasopressin among the vasopressors

A data viva placing vasopressin against noradrenaline and adrenaline. The discriminating data points: vasopressin is the only non-adrenergic agent — an endogenous PEPTIDE acting through V1 (vascular smooth muscle, Gq, vasoconstriction), V2 (renal collecting duct, Gs, aquaporin-2) and V3 (anterior pituitary, ACTH) — taught pharmacology. It is the catecholamine-resistant, catecholamine-sparing agent that works when adrenergic receptors are downregulated in septic shock and vasoplegia (Hiroto 2026); in septic shock it is second-line, ADDED to noradrenaline at a FIXED non-titrated taught-formulary dose of 0.03 to 0.04 units per min, reducing the noradrenaline requirement (Hiroto 2026); it has no beta-1 activity and so no tachyarrhythmia or metabolic effect (taught). Adverse effects: peripheral, digital and MESENTERIC ISCHAEMIA (V1, taught mapping) and HYPONATRAEMIA (V2, taught). Noradrenaline is the titrated first-line adrenergic agent (alpha-1, beta-1) for sustained vasoplegia (Hiroto 2026); adrenaline is the broad alpha-plus-beta catecholamine first-line in anaphylaxis and cardiac arrest (taught). The catecholamine and the peptide are used TOGETHER in septic shock. Desmopressin (DDAVP) is the V2-selective, non-vasoconstricting analogue for central diabetes insipidus, haemophilia/von Willebrand disease (factor VIII and vWF release — Vinjamuri 2025). Neonatal adjunct per the 4-RCT Yahya scope and delirium-null per Dong (vasopressin not studied) frame the selection logic.