sevoflurane + lidocaine + ketamine + dexmedetomidine + magnesium sulfate

This is a **combination anesthetic regimen** comprising five agents: - **Sevoflurane**: A volatile inhalational anesthetic, rapidly inducing and maintaining general anesthesia by modulating several ligand-gated ion channels, including GABA(A), glycine, nicotinic acetylcholine, serotonin, and glutamate receptors, as well as various ion currents. It is widely used due to rapid onset/offset, minimal airway irritation, and relative cardiovascular stability[1][3][4]. - **Lidocaine**: An amide local anesthetic and antiarrhythmic, which works primarily by blocking voltage-gated sodium channels, thereby preventing nerve impulse propagation and reducing pain sensation at the site of administration. - **Ketamine**: A non-barbiturate dissociative anesthetic and analgesic that is an antagonist at the NMDA (N-methyl-D-aspartate) receptor, producing analgesia, amnesia, and sedation with minimal respiratory depression. It also has sympathomimetic properties and preserves airway reflexes[7]. - **Dexmedetomidine**: A selective alpha-2 adrenergic receptor agonist, providing sedation, anxiolysis, and modest analgesia primarily through central alpha-2A receptor activation, reducing norepinephrine release. - **Magnesium sulfate**: An inorganic salt and CNS depressant; in anesthesia it acts as an NMDA receptor antagonist and calcium channel blocker, potentiating analgesia and reducing anesthetic and opioid requirements. This combination is not marketed under a single proprietary name but is used in complex anesthesia protocols for multimodal anesthesia, aiming to reduce the doses of individual agents, blunt nociceptive responses, provide hemodynamic stability, and speed recovery. It is most commonly employed in perioperative settings for balanced anesthesia or to spare the minimum alveolar concentration (MAC) of inhaled anesthetics such as sevoflurane[5].