Rebound Pain After Peripheral Nerve Blockade-Bad Timing or Rude Awakening?

Patients who have perioperatively benefited from regional anesthesia frequently report moderate to severe pain when the nerve block effects fade away. Over the past years, the term "rebound pain" has been introduced, suggesting a specific pathologic process. It is debated whether significant pain on block resolution reflects a separate and distinct pathologic mechanism potentially involving proinflammatory and neurotoxic effects of local anesthetics, or is simply caused by the recovery of sensory function at a timepoint when nociceptive stimuli are still intense, and moderate to severe pain should be anticipated. In that latter case, the phenomenon referred to as rebound pain could be considered a failure of pain management providers to devise an adequate analgesia plan. Whatever the ultimate designation, management of rebound pain should be proactive, by implementing multimodal analgesia, or tailoring the blockade to the expected trajectory of postoperative pain and managing patient expectations accordingly. Until we know more about the etiology and impact of this phenomenon, the authors suggest a more neutral designation such as "pain on block resolution."