Are Opioid-tolerant Patients Resistant to Local Anesthetic Nerve Blockade?: We Need More Information

Authors: Timothy J. Brennan, M.D., Ph.D. et al

THE management of acute pain in the opioid-tolerant patients is an important topic in perioperative medicine. In this issue of Anesthesiology, Liu and Gold¹ demonstrate that morphine administration that induces morphine tolerance in rats produces resistance to lidocaine-induced nerve blockade ex vivo.

Acute pain management can be quite challenging in opioid-tolerant patients. Opioids remain the most potent analgesic medications for treating acute pain and yet require greater dosages in patients with long-term use.  Administering larger doses of opioids not only leads to undesirable side effects  but often fails to provide adequate analgesia based on patient report. Further, multimodal analgesia with nonopioid analgesics such as ketamine,  acetaminophen, nonsteroidal antiinflammatory drugs, and local anesthetics has become the cornerstone of perioperative pain management in opioid-tolerant patients.  Rotating the opioid medication to a different opiate can improve efficacy by taking advantage of incomplete cross-tolerance among these medications, but the clinical evidence is limited.