Hyperbaric oxygen therapy (HBOT) involves the intermittent inhalation of 100% oxygen (O2) while being exposed to an increase in atmospheric pressure inside of a hyperbaric chamber. During HBOT, hemoglobin saturation increases thus increasing the O2 available and able to be delivered to tissues. HBOT was originally developed to treat decompression illness due to accidents experienced during diving. In recent years, it has been used to treat numerous different injuries and conditions, some examples of which include necrotizing soft tissue injuries, chronic wounds, traumatic ischemia, radiation injury, chronic pain, dysfunctional syndromes, fibromyalgia, chronic fatigue, headaches, and complex regional pain syndrome.
Chronic pain is described as pain that persists well past the usual course of disease or injury and can persist for many months to years in a continuous or intermittent manner. Pain can additionally occur without any identifiable cause. It can be difficult to treat, often requires a multidisciplinary approach, and is one of the more frequent reasons patients visit healthcare professionals. Due to the chronicity of pain (particularly musculoskeletal pain) and the lack of effective therapeutic options, other treatment paradigms (such as pharmacotherapy) on their own or as adjuncts to pre-existing therapies are being examined. HBOT has been postulated to be effective as an adjunctive treatment for the treatment of chronic pain in many conditions and is a viable option for patients experiencing chronic musculoskeletal pain.
One randomized controlled trial with a crossover active comparator and one prospective non-randomized cohort study formed the evidence base for this review. The RCT provided evidence to suggest that two months of hyperbaric oxygen therapy (HBOT) increases pain thresholds, physical functionality, and health-related quality of life while decreasing tender points and psychological distress in female patients with Fibromyalgia Syndrome (FMS) at three months post-treatment. In addition, according to single photon emission computed tomography analyses, the majority of patients were classified as responders to HBOT and were assessed as having beneficial changes in brain activity within the specific regions of the brain known to be previously associated with abnormal activity in patients with FMS.