title: Hyperbaric Oxygen Therapy: A New Treatment for Chronic Pain?
abstract: Hyperbaric oxygen therapy (HBOT) is a treatment providing 100% oxygen at a pressure greater than that at sea level. HBOT is becoming increasingly recognized as a potential treatment modality for a broad range of ailments, including chronic pain. In this narrative review, we discuss the current understanding of pathophysiology of nociceptive, inflammatory and neuropathic pain, and the body of animal studies addressing mechanisms by which HBOT may ameliorate these different types of pain. Finally, we review clinical studies suggesting that HBOT may be useful in treating chronic pain syndromes, including chronic headache, fibromyalgia, complex regional pain syndrome, and trigeminal neuralgia.
  
  
  
  A comprehensive search through MEDLINE, EMBASE, Scopus, and Web of Science for studies relating to HBOT and pain was performed using the following keywords: hyperbaric oxygen therapy or hyperbaric oxygen treatment (HBOT), nociceptive pain, inflammatory pain, neuropathic pain, HBOT AND pain, HBOT AND headache, HBOT AND fibromyalgia, HBOT AND complex regional pain syndrome, and HBOT AND trigeminal neuralgia.
  
  
  
  Twenty-five studies examining the role of HBOT in animal models of pain and human clinical trials were found and reviewed for this narrative review.
  
  
  
  HBOT has been shown to reduce pain using animal models. Early clinical research indicates HBOT may also be useful in modulating human pain; however, further studies are required to determine whether HBOT is a safe and efficacious treatment modality for chronic pain conditions.
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, ON, Canada.
authors.forename: Ainsley M
authors.initials: AM
authors.lastname: Sutherland
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, ON, Canada.
authors.forename: Hance A
authors.initials: HA
authors.lastname: Clarke
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, ON, Canada.|Department of Psychology, York University, Toronto, ON, Canada.
authors.forename: Joel
authors.initials: J
authors.lastname: Katz
authors.affiliation: Department of Anesthesia and Pain Management, Toronto General Hospital, University Health Network, Toronto, ON, Canada.|Hyperbaric Medical Unit, Department of Anesthesia and Pain Management, Toronto General Hospital, Toronto, ON, Canada.
authors.forename: Rita
authors.initials: R
authors.lastname: Katznelson
mesh_terms: D000818:Animals; D059350:Chronic Pain / Q000628:therapy*; D002986:Clinical Trials as Topic; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods*; D023421:Models, Animal
keywords: analgesia; animal models; cluster headache; complex regional pain syndromes; fibromyalgia; hyperbaric oxygen therapy; inflammation; neuropathic pain; nociception; review; trigeminal neuralgia