The Impacts of Local Anesthetics and Surgical Trauma on Immunity

Local anesthetics exert anti-inflammatory effects through mechanisms that extend beyond mere sodium channel blockade. Surgical trauma is a potent iatrogenic trigger of systemic immune dysregulation. The stress response to surgery activates the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system. Local anesthetics modulate nearly every facet of the innate immune response and modulate adaptive immunity. Local anesthetics, via their inhibition of cytokine production and leukocyte activation, may consequently mitigate DAMP release by attenuating the amplification of tissue damage within the inflammatory cascade. Preexisting patient comorbidities significantly modulate the immune response to anesthesia and surgical intervention. Bupivacaine and ropivacaine exhibit differential effects on neutrophil extracellular trap (NET) formation. The immunomodulatory effects of local anesthetics exhibit heterogeneity dependent on the route of administration, dosing regimens, and frequency of application. Hypoxia serves as a critical modulator of anesthetic-immune interactions. Surgical trauma frequently establishes a localized hypoxic microenvironment at the wound site. The interaction between anesthetic agents and anticancer therapies represents a burgeoning field of significant clinical relevance. Many chemotherapeutic agents exert their antitumor effects via immune-mediated mechanisms, thereby suggesting that anesthetic-induced immunosuppression could theoretically attenuate their efficacy. Surgical trauma and local anesthetics exert distinct yet interconnected influences on the immune system. Despite this observed potential, current evidence remains insufficient to warrant modifications in clinical practice. Addressing this knowledge gap necessitates large-scale randomized controlled trials, comprehensive molecular-level mechanistic investigations, and the development of validated immune biomarkers to inform perioperative anesthetic selection.