The ability of cold temperature to render regions of our bodies insensate is second nature. Cryoanalgesia, or the use of cold temperatures to treat pain, as in icing after a sports injury, causes neuropraxia, or slowing of peripheral nociceptive transmission. Such neuropraxia is different from the application of focal extreme cold to nerve branches, where nerve injury including Wallerian degeneration is induced (cryoneurolysis). Cryoneurolysis has been studied in humans and other animals with mixed results, depending on the time frame studied, and symptoms assessed. In this issue of Anesthesiology, Ilfeld et al.1 present a small, carefully conducted randomized controlled trial of percutaneous, ultrasound-guided preoperative intercostal nerve cryoneurolysis and its impact on pain outcomes to 1 yr.
Modern cryoneurolysis began in the 1970s to 1980s, with thoracotomy patients reporting lower pain scores and opioid consumption in the early postoperative time period.2 Concerns over the development of longer-term neuropathic...
