Advances in the treatment of neuropathic pain with hyperbaric oxygen.

Neuropathic pain (NPP) refers to the pain caused by primary or secondary injury or dysfunction of the peripheral or central nervous system, and usually requires multidisciplinary treatment. However, most pharmacological and non-pharmacological interventions can only temporarily and/or moderately improve pain-related symptoms, and they often produce unbearable adverse reactions or cause drug resistance. Hyperbaric oxygen (HBO2) therapy has been widely used in the clinical treatment of some diseases due to its advantages of safety, few side effects, no resistance, and non-invasiveness. In recent years, increasing numbers of basic and clinical studies have been conducted to investigate the efficacy and mechanism of HBO2 in the treatment of NPP, and great progress has been made in this field. In this paper, we briefly introduce the pathogenesis of NPP and therapeutic effects of HBO2 and summarize the mechanisms underlying the effects of HBO2 in treating NPP, which may provide reference for the clinical treatment of pain with HBO2.

[New Therapeutic Strategies and Future Issues in Hyperbaric Medicine].

Hyperbaric medicine includes two different medical fields: hyperbaric oxygenation (HBO) as emergency and intensive care, and diving medicine. Recent topics in hyperbaric therapy include radiation oncology and regenerative medicine. Of special interest are clinical studies of radiotherapy after HBO that were conducted at some institutes to evaluate its therapeutic effects for cancer patients. A few studies have shown that HBO improves memory disturbance following traumatic brain injury and hypoxic and ischemic events. There is a great possibility that HBO enhances the therapeutic effects of radiotherapy and potentiates regenerative medicine. Randomized controlled trials, however, have indicated the re-examination of its viable treatment effects in some conditions, including decompression illness, carbon monoxide poisoning, and serious soft tissue infection. As recent trends in the treatment of decompression illness have changed on the basis of clinical series, the laws related to diving and caisson work should be amended in the future.

Molecular and Therapeutic Aspects of Hyperbaric Oxygen Therapy in Neurological Conditions.

In hyperbaric oxygen therapy (HBOT), the subject is placed in a chamber containing 100% oxygen gas at a pressure of more than one atmosphere absolute. This treatment is used to hasten tissue recovery and improve its physiological aspects, by providing an increased supply of oxygen to the damaged tissue. In this review, we discuss the consequences of hypoxia, as well as the molecular and physiological processes that occur in subjects exposed to HBOT. We discuss the efficacy of HBOT in treating neurological conditions and neurodevelopmental disorders in both humans and animal models. We summarize by discussing the challenges in this field, and explore future directions that will allow the scientific community to better understand the molecular aspects and applications of HBOT for a wide variety of neurological conditions.

Comparison of preoxygenation with a high-flow nasal cannula and a simple mask before intubation during induction of general anesthesia in patients undergoing head and neck surgery: Study protocol clinical trial (SPIRIT Compliant).

BACKGROUND: To assess the arterial oxygen partial pressure (PaO2) at defined time points during preoxygenation and to compare high-flow heated humidified nasal oxygenation with standard preoxygenation using oxygen insufflation via a facemask for at least 5 minutes, before intubation during induction of general anesthesia. METHODS: This randomized, single-blinded, prospective study will be conducted in patients undergoing head and neck surgery. After standard monitoring, the artery catheter at the radial artery or dorsalis pedis artery will be placed and arterial blood gas analysis (ABGA) for baseline values will be performed simultaneously. Each group will be subjected to 1 of 2 preoxygenation methods (high-flow nasal cannula or simple facemask) for 5 minutes, and ABGA will be performed twice. After confirming intubation, we will start mechanical ventilation and check the vital signs and perform the final ABGA. DISCUSSION: This trial aims to examine the trajectory of PaO2 levels during the whole preoxygenation procedure and after intubation. We hypothesize that preoxygenation with the high-flow nasal cannula will be superior to that with the face mask. STUDY REGISTRATION: This trial was registered with the Clinical Trial Registry (NCT03896906; ClinicalTrials.gov).

Terapia de oxigenación hiperbárica en el tratamiento del dolor / Hyperbaric oxygenation therapy in pain treatment

El dolor crónico constituye un reto terapéutico especial. Se presenta una revisión narrativa sobre el papel del tratamiento de oxigenación hiperbárica (TOHB) en el tratamiento del dolor neuropático, y sus aplicaciones en dolor crónico, síndromes neurosensitivos disfuncionales y oncodolor. El conocimiento de las indicaciones de TOHB en algiología y su aplicación en la práctica médica puede contribuir a mejorar la calidad de vida del paciente. (AU)

Chronic pain represents a special therapeutic challenge. We present a narrative review on the role of Hyperbaric Oxygen Therapy (HBOT) in the treatment of neuropathic pain, and its applications in chronic pain, dysfunctional neurosensitive syndromes and oncological pain. The knowledge of the indications of HBOT in algiology and its application in medical practice can contribute to improve the quality of life of the patient. (AU)

Could Hyperbaric Oxygen Be a Solution in the Treatment of Spinal Infections?

Background and Objective: Pyogenic spinal infections are rare and potentially devastating, requiring prompt recognition and management. Parallel to the ever-increasing number of invasive spinal procedures, its incidence is on a steady rise, particularly in an expanding elderly population. The aim of this study was to evaluate the efficacy of hyperbaric oxygen (HBO2) therapy in the treatment of this heterogeneous group of disorders. Materials and Methods: Nineteen patients who were referred to our center for HBO2 with a clinical diagnosis of spinal infections (vertebral osteomyelitis, pyogenic spondylitis, spondylodiscitis, surgical site infection following spine surgery, epidural abscess) were retrospectively reviewed. Results: Infection resolution was adequately achieved in 12 of 13 patients (92.3%) on magnetic resonance imaging at the end of HBO2 treatment or during the first month of follow-up. The mean follow-up period was 11 months (range 1 month to 3 years). Conclusions: This study suggests that HBO2 therapy is efficacious in patients with pyogenic spinal infections complicated by primary therapy failure or by medical comorbidities that may impede the eradication of microbial infection and delay wound healing. HBO2 therapy may be useful for reducing long hospital stays, repeated surgeries, and morbidities.

Evaluation of hyperbaric oxygen therapy for spinal cord injury in rats with different treatment course using diffusion tensor imaging.

STUDY DESIGN: Animal study. OBJECTIVES: To evaluate the efficacy of hyperbaric oxygen (HBO) therapy for spinal cord injury (SCI) in rats with different treatment course using diffusion tensor imaging (DTI). SETTING: Hospital in Fuzhou, China. METHODS: Fifty adult Sprague-Dawley rats were grouped as: (A) sham-operated group (n = 10); (B) SCI without HBO therapy group (n = 10); (C) SCI with HBO therapy for 2 weeks (SCI+HBO2W) group (n = 10); (D) SCI with HBO therapy for 4 weeks (SCI+HBO4W) group (n = 10); (E) SCI with HBO therapy for 6 weeks (SCI+HBO6W) group (n = 10). Basso Beattie Bresnahan (BBB) scores and diffusion tensor imaging parameters including fractional anisotropy (FA), mean diffusivity (MD), radial diffusion (RD), and axial diffusion (AD) values in the injury epicenter, as well as 2 mm rostral and caudal to the injury epicenter were collected and analyzed 6 weeks post-injury. RESULTS: Higher BBB score and FA values were found in the SCI+HBO4W group than in the SCI and SCI+HBO2W groups (all P < 0.05), whereas no significant differences of these metrics were observed between the SCI+HBO4W and SCI+HBO6W groups. MD and RD values of the SCI+HBO4W group were significantly lower than those of the SCI group (all P < 0.01). FA values were positively correlated with BBB scores. MD and RD values were negatively correlated with BBB scores. CONCLUSION: DTI parameters, especially FA, could non-invasively and quantifiably evaluate the efficacy of HBO treatment for rats with SCI and 4 weeks may be the more appropriate treatment course.

Hyperbaric oxygen therapy: Antimicrobial mechanisms and clinical application for infections.

Hyperbaric oxygen therapy (HBOT) is a treatment procedure that involves breathing 100% O2 for a certain time and under a certain pressure. HBOT is commonly administrated as a primary or alternative therapy for different diseases such as infections. In this paper, we reviewed the general aspect of HBOT procedures, the mechanisms of antimicrobial effects and the application in the treatment of infections. Parts of the antimicrobial effects of HBOT are believed to result of reactive from the formation of reactive oxygen species (ROS). It is also said that HBOT enhances the antimicrobial effects of the immune system and has an additive or synergistic effect with certain antimicrobial agents. HBOT has been described as a useful procedure for different infections, particularly in deep and chronic infections such as necrotizing fasciitis, osteomyelitis, chronic soft tissue infections, and infective endocarditis. The anti-inflammation property of HBOT has demonstrated that it may play a significant role in decreasing tissue damage and infection expansion. Patients treated by HBOT need carful pre-examination and monitoring. If safety standards are strictly tracked, HBOT can be considered a suitable procedure with an apt rate of complication.

Hyperbaric oxygen and aerobic exercise in the long-term treatment of fibromyalgia: A narrative review.

Chronic pain is one of the most common clinical presentations in the primary care settings. In the US, Fibromyalgia (FM) affects about 1-3% of adults and commonly occurs in adults between the ages of 40-50 years. FM causes widespread muscular pain and tenderness with hyperalgesia and allodynia and may be associated with other somatic complaints. Hyperbaric oxygen therapy (HBOT) has been utilized and has recently shown promising effects in the management of FM and other chronic pain disorders. In HBOT, the intermittent breathing of 100% oxygen in a pressurized chamber where the pressure is higher than 1 atmosphere absolute (ATA) has been utilized. HBOT exhibits a significant anti-inflammatory effect through reducing production of glial cells and inflammatory mediators which results in pain alleviation in different chronic pain conditions. HBOT can also influence neuroplasticity and affects the mitochondrial mechanisms resulting in functional brain changes. In addition to that, HBOT stimulates nitric oxide (NO) synthesis which helps in alleviating hyperalgesia and NO-dependent release of endogenous opioids which seemed to be the primary HBOT mechanism of antinociception. Moreover, aerobic exercise and meditative movement therapies (MMT) have gained attention for their role in pain alleviation through different anti-inflammatory and antioxidant mechanisms. In this review, we aim to elucidate the different mechanisms of HBOT and aerobic exercise in attenuating pain as adjuvant therapy in the multidisciplinary treatment strategy of chronic pain, and more particularly fibromyalgia.

Hyperbaric Oxygen Therapy After Acute Thoracic Spinal Cord Injury: Improvement of Locomotor Recovery in Rats.

STUDY DESIGN: A controlled laboratory study. OBJECTIVE: The aim of this study was to analyze the effectiveness of hyperbaric therapy (HT) using mild and moderate models of spinal cord injury (SCI). SUMMARY OF BACKGROUND DATA: SCI can cause permanent impairment with socioeconomic consequences. The motor deficit occurs by two mechanisms: destruction of neuronal cells and local inflammatory response, resulting in hypoxia. HT acts by increasing oxygen in the injured area. METHODS: Thoracic laminectomy was performed in 72 female Wistar rats. The MASCIS impactor was used at 12.5 mm (n = 35) and 25 mm (n = 35) of height to perform, respectively, mild and moderate SCI. Muscle strength was assessed through the Basso, Beattie, and Bresnahan scale (BBB) on days 1, 7, 14, 21, and 28 after SCI. The animals were randomized into five subgroups with seven animals each: (1) control group had SCI without HT; (2) HT 30 minutes after SCI; (3) HT 30 minutes after SCI and daily for 7 days; (4) HT 12 hours after SCI; and (5) HT 12 hours after SCI and daily for 7 days. HT was performed at 2.5 atm for 1 hour. RESULTS: There was a linear relationship between injury severity and motor deficit until day 21, with similar BBB scores on day 28. A pattern of uniform lesions was observed in the mild SCI, with lower variation of BBB when compared with moderate SCI. All animals that underwent HT had significant improvement in motor function and histology when compared with control group. Regardless of the injury model, animals submitted to 7-day protocols had an early improvement in motor function and a smaller area of histological injury. CONCLUSION: The present study reported that the sooner HT is begun after mild and moderate SCI and the larger the number of sessions, the greater and earlier is the motor recovery and smaller is the tissue injury. LEVEL OF EVIDENCE: N/A.

Primum Non Nocere and the 5 Rights.

Overutilization of hyperbaric oxygen therapy (HBOT) is commonplace and primarily associated with outpatient wound care. While the number of hospitals providing HBOT is at an all-time high, the number of those willing to treat patients in immediate need is at an all-time low. Huge areas of the country, including major population areas, are now completely devoid of 24/7 HBOT availability and inpatient access. Purchasers of healthcare, including the Centers for Medicare and Medicaid Services, have become increasingly concerned to the point that several strategies have been introduced to constructively deal with this issue. This commentary serves as a counterpoint to concerns that one such approach, prior authorization of elective indications, adversely delays medically necessary care. The historical evolution of HBOT practice will be described to underscore how this problem has become so widespread and, to date, largely unchecked. It will also address the paradoxical national crisis of access for emergencies.

Hyperbaric medicine today: an historically noble discipline challenged by loss of critical access and overutilization - invited commentary.

As the title implies, much appears amiss with hyperbaric medicine. Long recognized for its life-saving, CNS-sparing,infection-fighting and tissue-salving attributes, its current application has been rightly called into question by a broad cross-section of health care delivery system stakeholders [1, 2, 3, 4, 5]. This paper will examine what lies behind the stunning loss of availability for a majority of the Federal Drug Administration-approved uses, arguably those for which patients have the most to gain. It will address overutilization in the context of an erosion of practice standards and widespread manipulation of the reimbursement process. It will make suggestions aimed at restoring its broader availability across the full extent of FDA-approved uses. Finally, it offers guidance to ensure that HBO2 therapy is employed only when medically necessary by adoption of the drug administration "rights" principle, namely the right indication for the right patient at the right time and only for the right amount of time.

Treating Decompression Sickness: Military Flight Simulation Site-Community Hospital Partnership.

BACKGROUND: High-altitude flight simulation familiarizes military trainees with the symptoms of hypoxia to prepare them for emergency situations. Decompression sickness (DCS) can occur as a result of these simulations. In cases when ground-level supplemental oxygen does not resolve symptoms, hyperbaric oxygen (HBO) therapy is indicated. Many military hyperbaric chambers have been closed because of cost reductions, necessitating partnerships with community hospitals to ensure access to treatment. MATERIALS AND METHODS: This article describes the unique arrangement between a community hospital in Colorado and a military training site to treat DCS cases emergently. We gathered cost data from the community hospital to estimate and compare the cost of providing HBO therapy in the hospital versus a standalone chamber similar to the former military hyperbaric chamber. RESULTS: Since the closure of the military hyperbaric chamber, the community hospital treated an estimated 50 patients with DCS requiring HBO therapy attributed to high-altitude flight simulation between October 2003 and April 2015. Cost to the institution providing HBO treatment varies widely on the basis of patient volume. Assuming a volume of five treatments, per-treatment cost at a standalone center is $95,380. In contrast, per-treatment cost at the hospital assuming a volume of 1,000 treatments commensurate with the hospital's ability to bill for other services is $698 per treatment. CONCLUSION: The cost analysis demonstrates that the per-treatment cost of operating a standalone HBO therapy center may be greater than 100 times that of operating a center at a community hospital, suggesting the arrangement is beneficial to the military.

Effects of Hyperbaric Oxygen Therapy on Inflammasome Signaling after Traumatic Brain Injury.

OBJECTIVE: Neuroinflammation plays an important role in secondary tissue damage after traumatic brain injury (TBI). Recently, the inflammasome-mediated inflammatory pathway has been observed in the inflammatory response of TBI. In this study, we investigated the influence of hyperbaric oxygen therapy (HBOT) on inflammasome activation after TBI. METHODS: The experimental mice were randomly divided into 4 groups as follows: sham-operated normobaric air (21% O2 at one absolute atmosphere), HBOT only, TBI + normobaric air and TBI + HBOT. Following the evaluation of motor deficits and brain edema, the expression of inflammasome components and effectors was measured by qRT-PCR and Western blotting. Moreover, alterations in IL-1ß, IL-18 and high-mobility group box 1 (HMGB1) were calculated by enzyme-linked immunosorbent assay at each time point after injury. RESULTS: HBOT improved motor score and reduced brain edema. Furthermore, it suppressed protein expression of inflammasome components and reduced the levels of IL-1ß and IL-18, accompanied by the reduction of HMGB1 in brain tissues and serum. CONCLUSION: These results suggest that HBOT may alleviate the inflammatory response after TBI by inhibiting the activation of inflammasome signaling.