Perioperative Hyperalgesia and Associated Clinical Factors.

PURPOSE OF REVIEW: Pain has an important evolutionary role because it serves as an essential warning device to damaging stimuli. The perioperative setting is a unique environment where clinicians must accurately diagnose and address the source of pain. Modern-day perioperative pain control continues to be unsatisfactory. Nearly half of all surgical patients have moderate to severe pain postoperatively, and 24% experience inadequate pain relief. Furthermore, over half of the patients develop chronic pain after thoracotomies, mastectomies, and limb amputation surgeries. Hyperalgesia in the perioperative setting is an important and under-recognized source of morbidity during the perioperative course.

RECENT FINDINGS: Key sources of perioperative hyperalgesia include nociceptive-induced pain with surgical trauma, opioid-induced hyperalgesia, and inadequate control of pain in the preoperative setting. Research also hints that inhaled anesthetics may also play a role in the development of perioperative hyperalgesia. Despite new evidence, hyperalgesia remains difficult to diagnose and treat. In our manuscript, we aim to help clinicians develop strategies to define, understand, diagnose, and treat perioperative hyperalgesia. Common mechanisms of perioperative hyperalgesia are delineated in an organized fashion with clinicians as the target audience.