Non-Opioid Strategies and Multimodal Blockade

This phenomenon is triggered by the acute activation of spinal excitatory glutamatergic pathways through Protein Kinase C-mediated phosphorylation of metabotropic NMDA receptors, reflexively decreasing the patient's pain threshold and increasing the rescue analgesic need during hospitalization.

The Four Pharmacological Pillars of the OFA

To optimally suppress sympathetic and autonomic responses to surgical trauma without the clinical need to resort to opioids, the OFA strategy synergistically combines agents with different systemic analgesic and hypnotic profiles:

1. Dexmedetomidine: As a selective α₂-adrenergic agonist, it provides exceptional autonomic hemodynamic stability and analgesia at the level of the spinal posterior horns.
2. Magnesium Sulfate: Acts as a physiological antagonist of L-type calcium channels and blocker of the ionotropic channel associated with the excitatory NMDA receptor, potently decreasing central pain sensitization.
3. Lidocaine Intravenous Infusion: Systemically blocks axoplasmic axonal sodium channels at low doses, reducing the release of peripheral inflammatory mediators and offering a postoperative prokinetic analgesic and intestinal motility effect.
4. Regional Anesthesia and Peripheral Blocks: Complete blockade of the conduction of afferent nociceptive signals to the spinal cord by targeted local injections of long-acting anesthetic amides.