PROLONGED NERVE BLOCKAGE BY THE COMBINATION OF LOCAL ANESTHETICS AND GLUCOCORTICOIDS

摘要

It has been discovered that glucocorticoids prolong nerve blockage produced by release of local anesthetic agents from local delivery systems such as microspheres. The degree of prolongation is proportional to the strength of the glucocorticoid. Preferred anesthetics are local anesthetics that induce local pain relief or numbness, especially bupivacaine, dibucaine, etidocaine, and tetracaine, most preferably the free base of the local anesthetic. Preferred glucocorticoids are dexamethasone, methylprednisolone, betamethasone, and hydrocortisone. Synthetic polymers are preferred for formation of microparticles for release of the local anesthetic agent and glucocorticoid. The glucocorticoid is preferably incorporated into the polymeric matrix or administered with the microspheres. The microspheres are injected at the site where the anesthetic is to be released. This can be at the time of surgery, or irrigation or perfusion of a wound.