Nephroprotective effects of hyperbaric oxygen therapy in murine models of acute kidney injury: A systematic review and meta-analysis.

AIMS: Acute kidney injury (AKI) is a life-threatening condition marked by sudden kidney function loss and azotemia. While its management is limited to supportive care, the effects of hyperbaric oxygen therapy (HBO) on AKI remain a subject of conflicting animal research. This study aimed to systematically review and meta-analyze HBO's effects on renal function biomarkers serum creatinine (SCr) and blood urea nitrogen (BUN) in murine AKI models, also exploring tissue-level nephroprotection. MAIN METHODS: The PUBMED, SciELO, and LILACS databases were searched until September 5, 2024. Effect sizes of HBO on SCr and BUN levels were expressed as standardized mean difference (SMD) alongside 95 % confidence interval (CI), calculated by random-effects model. Extracted data also included murine specie/strain, HBO parameters, AKI induction method (toxic, ischemic, others), and histological findings. Study quality and publication bias were respectively assessed using the CAMARADES checklist and Egger's test. This review adhered to PRISMA guidelines and was registered in PROSPERO (CRD42022369804). KEY FINDINGS: Data synthesis from 21 studies demonstrates that HBO effectively reduces azotemia in AKI-affected animals (SCr's SMD = -1.69, 95 % CI = -2.38 to -0.99, P < 0.001; BUN's SMD = -1.51, 95 % CI = -2.32 to -0.71, P < 0.001) while mitigating histological damage. Subgroup analyses indicate that HBO particularly benefits ischemic and other AKI types (P < 0.05). In contrast, data from toxic AKI models were inconclusive due to insufficient statistical power (P > 0.05, 1-ß < 30 %). SIGNIFICANCE: This meta-analysis provides compelling evidence supporting the adjunctive use of HBO in AKI management.

Bispectral index with density spectral array (BIS-DSA) monitoring in a patient with inner ear and cerebral decompression sickness.

Bispectral index with density spectral array (BIS-DSA) monitoring during hyperbaric oxygen therapy of a case with inner ear and cerebral decompression sickness is described. During the initial treatment, a particular DSA pattern was found, which resolved after four treatments. Clinical resolution of the symptoms accompanied this improvement. The particular BIS-DSA pattern described in this case is concordant with a potential hypo-perfusion of the cortex related to decompression stress. This case suggests that BIS-DSA monitoring may be an easy, cost-effective, and viable form of neuro-monitoring during hyperbaric oxygen treatment for decompression sickness.

Mild hyperbaric oxygen exposure protects heart during ischemia/reperfusion and affects vascular relaxation.

Mild hyperbaric oxygen therapy (mHBOT) is an adjuvant therapy used in conditions where tissue oxygenation is reduced and is implemented using pressures less than 1.5 ATA and 100% O2 (instead of the classical HBOT at 1.9-3 ATA) which results in cheaper, easier to implement, and equally effective. mHBOT is offered for wellness and beauty and as an anti-aging strategy, in spite of the absence of studies on the cardiovascular system. Consequently, we investigated the impact of mHBOT on the cardiovascular system. Mechanical and energetic parameters of isolated heart submitted to ischemia/reperfusion injury and arterial contractile response from mHBOT-exposed rats were evaluated. In the heart, mHBOT increased pre-ischemic velocity of contraction and ischemic end-diastolic pressure and developed pressure and contractile economy during reperfusion. mHBOT decreased infarct size and increased the plasma nitrite levels. In the artery, mHBOT increased acetylcholine sensitivity. mHBOT protects the heart during ischemia/reperfusion and affects vascular relaxation.

Hyperbaric Medicine in Pediatrics - reality of a Portuguese reference center.

OBJECTIVE: To identify and characterize the population of Pediatric patients referred to our hyperbaric oxygen therapy center. METHODS: Retrospective and observational study, including pediatric patients treated with hyperbaric oxygen therapy, from 2006 to 2021, at the hyperbaric medicine reference center in the north of Portugal. Variables of interest were extracted from electronic medical records. RESULTS: Our study included 134 patients. The most frequent reasons for referral were carbon monoxide poisoning (n=59) and sudden sensorineural hearing loss (n=41). In 75 cases (56%), treatment was initiated in an urgent context. Symptom presentation at Emergency Department varied among patients, the most frequent being headache and nausea/vomiting. Concerning carbon monoxide poisoning, the most common sources were water heater, fireplace/brazier, and boiler. Regarding adverse effects, it was identified one case of intoxication by oxygen and four cases of middle ear barotrauma. CONCLUSIONS: The most frequent cause for referral was carbon monoxide poisoning. All patients evolved favorably, with few side effects being reported, emphasizing the safety of this therapy. While most pediatricians may not be aware of the potential benefits arising with hyperbaric oxygen therapy, it is of upmost importance to promote them, so that this technique is increasingly implemented.

Hyperbaric oxygen therapy increases the effect of 5-fluorouracil chemotherapy on experimental colorectal cancer in mice.

Tumor hypoxia may compromise the results of chemotherapy for treating colorectal cancer because it stimulates angiogenesis and the release of tumor growth factors. Hyperbaric oxygen (HBO) supplementation may potentiate the effects of chemotherapy in such cases. This study aimed to assess the effect of HBO therapy combined with chemotherapy on the treatment of colorectal cancer in mice. C57BL6 mice were submitted to the intrarectal instillation of N-methyl-N-nitrosoguanidine (MNNG) and treated with 5-fluorouracil (5FU) and/or HBO therapy. The MNNG group presented the highest dysplastic crypt rate. The 5FU + HBO group presented the highest rate of apoptotic cells per dysplastic crypt. The 5FU group presented the highest expression of hypoxia-inducible factor-1 alpha and CD44. HBO therapy increased the effect of 5FU on the treatment of the experimental colorectal neoplasia in mice.

[Cerebral gas embolism as a complication of diffuse interstitial lung disease] / Embolismo gaseoso cerebral como complicación de una enfermedad pulmonar intersticial difusa.

Introduction: Cerebral gas embolism is an unusual but extremely serious condition that occurs when air is introduced into the arterial or venous circulation of the brain. Although rare, it can lead to significant neurological deficits and even the death of the patient. Clinical Case: 76-year-old patient with pre-existing diffuse interstitial lung disease, who experienced a massive stroke due to spontaneous pneumomediastinum. Her presentation included confusion, seizures, and motor weakness. Imaging tests revealed air bubbles in the cerebral sulci and hypodense areas in the cerebellum and parietooccipitals. In addition, pneumothorax and air in the upper mediastinum were noted on chest radiographs and chest CT scan. Despite therapeutic measures such as hyperbaric oxygen, the patient unfortunately died due to multiple organ failure. Discussion: The diagnosis of cerebral gas embolism generally involves performing a cerebral computed tomography, which is highly sensitive for detecting the presence of air in the cerebral vessels. Management includes monitoring of vital and neurological signs, as well as specific measures such as airway closure, venous catheter aspiration, Trendelenburg positioning, and hyperbaric oxygen. Conclusion: Cerebral gas embolism is a potentially fatal condition that requires a brain computed tomography for diagnosis and it is vitally important to know the prevention measures to avoid the appearance of this complication and also to know the general measures to adopt when it occurs.

Introducción: La embolia gaseosa cerebral es una afección inusual pero extremadamente grave que se produce cuando se introduce aire en la circulación arterial o venosa del cerebro. Aunque poco común, puede derivar en déficits neurológicos significativos e incluso la muerte del paciente. Caso Clínico: Paciente de 76 años con una enfermedad pulmonar intersticial difusa preexistente, que experimentó un ictus masivo debido a un neumomediastino espontáneo. Su presentación incluyó confusión, convulsiones y debilidad motora. Las pruebas de imagen revelaron burbujas de aire en los surcos cerebrales y áreas hipodensas en el cerebelo y parietooccipitales. Además, se observó neumotórax y aire en el mediastino superior en las radiografías de tórax y la tomografía torácica. A pesar de las medidas terapéuticas como el oxígeno hiperbárico, la paciente lamentablemente falleció debido al fallo multiorgánico. Discusión: El diagnóstico de embolia gaseosa cerebral generalmente implica la realización de una tomografía computarizada cerebral, que es altamente sensible para detectar la presencia de aire en los vasos cerebrales. El manejo incluye el control de las constantes vitales y neurológicas, así como medidas específicas como cierre de la entrada de aire, aspiración de catéteres venosos, posicionamiento de Trendelenburg y oxígeno hiperbárico. Conclusión: La embolia gaseosa cerebral es una afección potencialmente mortal que requiere una tomografía computarizada cerebral para el diagnóstico y de vital importancia conocer las medidas de prevención para evitar la aparición de esta complicación y así mismo conocer las medidas generales a adoptar cuando ésta se presenta.

Oxigenoterapia hiperbárica. Sus aplicaciones en Cirugía Plástica / Hyperbaric oxygen therapy. Its applications in Plastic Surgery

La oxigenoterapia hiperbárica (OHB) puede mejorar la cicatrización de las heridas. La hipoxia, la alteración de la angiogénesis y la inflamación prolongada son condiciones constantes que la OHB favorece su reversibilidad; hace ya muchos años que, en el listado de indicaciones reconocidas por Sociedades Científicas que rigen esta práctica, se encuentra como indicación aceptada para el tratamiento coadyuvante en injertos o colgajos en riesgo isquémico, como también en heridas refractarias; en la última década, paulatinamente, con la difusión y el aumento de las facilidades para acceder a equipos hiperbáricos, las indicaciones se extendieron al área de la cirugía plástica, para tratamiento de complicaciones posoperatorias en tejidos isquémicos o necrosados y también para preacodicionamiento preoperatorio y sostén posoperatorio de cierto grupo de pacientes con mayor riesgo de sufrir una complicación, en las lipotransferencias como coadyuvante para aumento de la preservación de una mayor cantidad de tejido graso. Las publicaciones al respecto son cada día más frecuentes, algunas presentan un pequeño número de casos, otras son estudios de cohorte retrospectivos, con un nivel de evidencia elevado. El objetivo de este artículo es presentar el concepto básico de los efectos de la OHB, referencia al estado actual de las distintas indicaciones en uso en cirugía plástica y medicina cosmética y la experiencia personal al respecto.

Hyperbaric oxygen therapy (HOT) can improve wound healing, hypoxia, alteration of angiogenesis and prolonged infl ammation are constant conditions that HOT favors its reversibility for many years now, in the list of indications recognized by Scientifi c Societies. that govern this practice, is a recognized indication for adjuvant treatment in grafts or fl aps at ischemic risk, as well as in refractory wounds; In the last decade, gradually, with the dissemination and increase in the facilities to access hyperbaric equipment, the indications were extended to the area of plastic surgery, for the treatment of post-operative complications in ischemic or necrotic tissues as well as for preconditioning. operative and post-operative support of a certain group of patients with a higher risk of suff ering a complication, in lipotransferences as an adjuvant to increase the preservation of a greater amount of fatty tissue. Publications in this regard are becoming more frequent every day, some present a small number of cases, others are retrospective cohort studies, with a high level of evidence. The objective of this article is to present the basic concept of the eff ects of HOT, reference to the current state of the diff erent indications in use in plastic surgery, and cosmetic medicine and personal experience in this regard

The effect of hyperbaric oxygen therapy in head and neck cancer patients with radiation induced dysphagia-a systematic review.

PURPOSE: The aim of this systematic review was to assess the role of hyperbaric oxygen therapy  (HBOT) in patients with dysphagia after radiation therapy for head and neck cancer. METHOD: A systematic search was conducted in the electronic databases Ovid MEDLINE, Ovid Embase, and Cochrane Central Register of Controlled Trials for relevant studies until March 14, 2023. No restriction on language or publication date. The criteria for inclusion: patients with HNC who had received both radiation therapy and HBOT as 1) a preventive treatment against swallowing difficulties, 2) to preserve swallowing function, or 3) to promote swallowing difficulties. RESULTS: We identified 1396 records. After removal of 31 duplicates, 1365 records were accessible for title and abstract screening. This yielded 53 studies for full text assessment. Six studies met the eligibility criteria and were included for qualitative analysis. CONCLUSION: Evidence of HBOT benefits in patients with dysphagia after radiation therapy for head and neck cancer is inconsistent. Well-designed studies using validated outcome measures and long-term follow-up are warranted.

Paciente con enfermedad descompresiva del oído interno / Patient with inner ear decompression sickness

Introducción: La enfermedad descompresiva es un síndrome clínico complejo causado por la sobresaturación de gases respiratorios en la sangre y los tejidos, después de una reducción abrupta de la presión ambiental, que puede presentarse como parte de los accidentes de buceo. Dada su baja prevalencia se da a conocer una de sus formas de presentación en los servicios de urgencias, que requiere rapidez en el diagnóstico y conducta terapéutica inmediata. Objetivo: Presentar un caso grave de enfermedad descompresiva del oído interno. Caso clínico: Paciente masculino de 71 años de edad, buzo aficionado y antecedente de un accidente vascular encefálico isquémico hace aproximadamente 1 año. Realizó inmersiones, luego de las cuales comenzó a presentar síntomas como mareos, náuseas, vómitos copiosos, inestabilidad para la marcha y manifestaciones sensitivas en la cara. Horas después de ser evaluado en centro médico de urgencia, sin diagnóstico específico, se trasladó al cuerpo de guardia del hospital, para su valoración por el especialista en medicina subacuática. Conclusiones: La orientación diagnóstica de un paciente con enfermedad descompresiva requiere derivación urgente a un centro de tratamiento de enfermedades disbáricas(AU)

Introduction: Decompression illness is a complex clinical syndrome caused by supersaturation of respiratory gases in the blood and tissues, after an abrupt reduction in environmental pressure, which can occur as part of diving accidents. Given its low prevalence, one of its forms of presentation is revealed in emergency services, which requires speed in diagnosis and immediate therapeutic conduct. Objective: To present a severe case of decompressive disease of the inner ear. Clinical case: 71-year-old male patient, amateur diver, with a history of an ischemic stroke approximately 1 year ago. He performed dives, after which he began to present symptoms such as dizziness, nausea, copious vomiting, unsteadiness in walking, and sensitive manifestations on the face. Hours after being evaluated at the emergency medical center, without a specific diagnosis, he was transferred to the hospital's emergency room, for evaluation by the underwater medicine specialist. Conclusions: The diagnostic orientation of a patient with decompression illness requires urgent referral to a center for the treatment of dysbaric diseases(AU)

Hyperoxia: Effective Mechanism of Hyperbaric Treatment at Mild-Pressure.

HBOT increases the proportion of dissolved oxygen in the blood, generating hyperoxia. This increased oxygen diffuses into the mitochondria, which consume the majority of inhaled oxygen and constitute the epicenter of HBOT effects. In this way, the oxygen entering the mitochondria can reverse tissue hypoxia, activating the electron transport chain to generate energy. Furthermore, intermittent HBOT is sensed by the cell as relative hypoxia, inducing cellular responses such as the activation of the HIF-1α pathway, which in turn, activates numerous cellular processes, including angiogenesis and inflammation, among others. These effects are harnessed for the treatment of various pathologies. This review summarizes the evidence indicating that the use of medium-pressure HBOT generates hyperoxia and activates cellular pathways capable of producing the mentioned effects. The possibility of using medium-pressure HBOT as a direct or adjunctive treatment in different pathologies may yield benefits, potentially leading to transformative therapeutic advancements in the future.

Hyperbaric oxygen therapy enhances graft healing and mechanical properties after anterior cruciate ligament reconstruction: An experimental study in rabbits.

Hyperbaric oxygen therapy (HBOT) has proven successful in wound healing. However, its potential effects on anterior cruciate ligament (ACL) injuries remain uncertain. This study aimed to investigate the impact of HBOT on graft healing following ACL reconstruction in rabbits. Male New Zealand rabbits underwent ACL reconstruction and were randomly divided into two groups: the HBOT group and the ambient air group. The HBOT group received 100% oxygen at 2.5 atmospheres absolute for 2 h daily for 5 consecutive days, starting from the first day after surgery. The ambient air group was maintained in normal room air throughout the entire period. After 12 weeks following the surgery, animals were euthanized, and their knees were harvested for analysis. The HBOT group demonstrated superior graft maturation and integration in comparison to the ambient air group, as evidenced by lower graft signal intensity on magnetic resonance imaging, decreased femoral and tibial tunnel size, and higher bone mineral density values on high-resolution peripheral quantitative computed tomography scans. Additionally, biomechanical testing indicated that the HBOT group had greater load to failure and stiffness values than the ambient air group. In conclusion, the adjuvant use of HBOT improved ACL graft maturation and integration, reduced tunnel widening, and enhanced the biomechanical properties of the graft. These results may provide important insights into the potential clinical application of HBOT as a therapeutic intervention to enhance graft healing after ACL reconstruction, paving the way for further research in this area.

Evaluation of oxidative stress in an experimental model of Crohn's disease treated with hyperbaric oxygen therapy.

INTRODUCTION: Treatments of Inflammatory Bowel Disease (IBD) are able to control symptoms in most cases, however, a fraction of patients do not improve or have a loss of response to treatments, making it important to explore new therapeutic strategies. Hyperbaric oxygen therapy (HBO) may represent one of them. The aim of this study was to evaluate the effects of HBO therapy in an experimental model of IBD. METHODS: Sixty male BALBc mice were divided into six groups. Group 1 was colitis-induced with trinitrobenzene sulfonic acid (TNBS) + ethanol, group 2 received TNBS + ethanol plus HBO, group 3 received only ethanol, group 4 received ethanol plus HBO, group 5 received saline solution, and group 6 received saline solution plus HBO. HBO was performed for four days, subsequently, the mice were evaluated daily. At the end of the study, samples from the intestine were collected for histological analysis as well as for measurement of antioxidant enzymes and cytokine levels. RESULTS: HBO significantly improved the clinical and histological status of the animals. Treatment with HBO increased the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) in all of the groups; moreover, the difference was only significant between the TNBS and TNBS + HBO groups and treatments promoted a reduction in the proinflammatory cytokines IFN-γ, IL-12, IL-17 and TNF-α and increased the anti-inflammatory cytokines IL-4 and IL-10, with no changes in IL-13. CONCLUSION: HBO effectively treats TNBS-induced colitis by increasing the activity of antioxidant enzymes and modulating cytokine profiles.

Hyperbaric oxygen treatment increases intestinal stem cell proliferation through the mTORC1/S6K1 signaling pathway in Mus musculus.

BACKGROUND: Hyperbaric oxygen treatment (HBOT) has been reported to modulate the proliferation of neural and mesenchymal stem cell populations, but the molecular mechanisms underlying these effects are not completely understood. In this study, we aimed to assess HBOT somatic stem cell modulation by evaluating the role of the mTOR complex 1 (mTORC1), a key regulator of cell metabolism whose activity is modified depending on oxygen levels, as a potential mediator of HBOT in murine intestinal stem cells (ISCs). RESULTS: We discovered that acute HBOT synchronously increases the proliferation of ISCs without affecting the animal's oxidative metabolism through activation of the mTORC1/S6K1 axis. mTORC1 inhibition by rapamycin administration for 20 days also increases ISCs proliferation, generating a paradoxical response in mice intestines, and has been proposed to mimic a partial starvation state. Interestingly, the combination of HBOT and rapamycin does not have a synergic effect, possibly due to their differential impact on the mTORC1/S6K1 axis. CONCLUSIONS: HBOT can induce an increase in ISCs proliferation along with other cell populations within the crypt through mTORC1/S6K1 modulation without altering the oxidative metabolism of the animal's small intestine. These results shed light on the molecular mechanisms underlying HBOT therapeutic action, laying the groundwork for future studies.

Hyperbaric oxygen therapy as an adjunctive treatment for COVID-19-associated mucormycosis: a report of two cases. / Oxigenoterapia hiperbárica como tratamiento complementario en mucormicosis asociada con la COVID-19: a propósito de dos casos.

OBJECTIVE.: We present the first two cases reported in Peru of the use of adjuvant hyperbaric oxygen therapy (HBOT) in patients with COVID-19-associated mucormycosis (CAM). The first case is a 41-year-old woman, with pain in the left side of the face and palatine region with purulent rhinorrhea for a month. Only an oroantral fistula was found during physical examination. The second case is a 35-year-old male, with decreased left visual acuity and palatal pain with a fistula, draining purulent secretion for four months. Both patients have history of diabetes, had moderate COVID-19 four months prior to admission, and received corticosteroid therapy for this diagnosis. Tomographic evaluation of both patients showed involvement of the maxillary sinus and surrounding bone tissue; both received diagnostic and therapeutic nasal endoscopy for debridement. Histological analysis showed that the samples were compatible with mucormycosis. The patients underwent debridement and were treated with amphotericin B deoxycholate; however, they presented torpid evolution. Then, HBOT was added and the patients showed an evident improvement after four weeks of treatment with subsequent controls without the presence of mucormycosis. We highlight the favorable evolution of these patients while receiving HBOT as treatment for a disease with high morbimortality, which emerged during the pandemic.

Clinical and biochemical short-term effects of hyperbaric oxygen therapy on SARS-Cov-2+ hospitalized patients with hypoxemic respiratory failure.

BACKGROUND: Hyperbaric oxygen therapy (HBOT) has been proposed to address COVID-19- associated respiratory failure. However, its biochemical effects are poorly known. METHOD: 50 patients with hypoxemic COVID-19 pneumonia were divided into C group (standard care) and H group (standard care plus HBOT). Blood was obtained at t = 0 and t = 5 days. Oxygen saturation (O2 Sat) was followed up. White blood cell (WC) count, lymphocytes (L) and platelets (P) and serum analysis (glucose, urea, creatinine, sodium, potassium, ferritin, D dimer, LDH and CRP) were carried out. Plasma levels of sVCAM, sICAM, sPselectin, SAA and MPO, and of cytokines (IL-1ß, IL-1RA, IL-6, TNFα, IFNα, IFNγ, IL-15, VEGF, MIP1α, IL-12p70, IL-2 and IP-10) were measured by multiplex assays. Angiotensin Converting Enzyme 2 (ACE-2) levels were determined by ELISA. RESULTS: The average basal O2 Sat was 85 ± 3%. The days needed to reach O2 Sat >90% were: H: 3 ± 1 and C: 5 ± 1 (P < 0,01). At term, H increased WC, L and P counts (all, H vs C: P < 0,01). Also, H diminished D dimer levels (H vs C, P < 0,001) and LDH concentration (H vs C, P < 0.01]. At term, H showed lower levels of sVCAM, sPselectin and SAA than C with respect to basal values (H vs C: ΔsVCAM: P < 0,01; ΔsPselectin: P < 0,05; ΔSAA: P < 0,01). Similarly, H showed diminished levels of TNFα (ΔTNFα: P < 0,05) and increased levels of IL-1RA and VEGF than C respect to basal values (H vs C: ΔIL-1RA and ΔVEGF: P < 0,05). CONCLUSION: Patients underwent HBOT improved O2 Sat with lower levels of severity markers (WC and platelets count, D dimer, LDH, SAA). Moreover, HBOT reduced proinflammatory agents (sVCAM, sPselectin, TNFα) and increased anti-inflammatory and pro-angiogenic ones (IL-1RA and VEGF).

Protocol of HOTFy: randomised clinical trial to hyperbaric oxygen therapy in fibromyalgia.

INTRODUCTION: Fibromyalgia is a polysymptomatic syndrome with a prevalence between 0.2% and 13% of the population and causes work disabilities in approximately half of affected patients. Several treatments to fibromyalgia have been proposed with partial improvement. This study aims to evaluate the efficacy of hyperbaric oxygen therapy and when it should be introduced to fibromyalgia. METHODS AND ANALYSIS: This is a protocol for an open-label, crossover, randomised clinical trial comparing treatment with hyperbaric oxygen therapy and standardised treatment to fibromyalgia. In the proposed study, 56 individuals with fibromyalgia will be randomised in a 1:1 ratio into a single, fixed, random block, in which one group will receive hyperbaric oxygen therapy and another will receive standard treatment. Subsequently, the groups will be crossed. Participants will be evaluated at baseline, eight and 16 weeks based on functional impairment assessed with the Fibromyalgia Impact Questionnaire-Brazilian Portuguese version, psychopathological symptoms questionnaire and short-form quality of life questionnaire. The improvement of symptoms concerning the moment of therapy used will be compared between groups. For sample size calculation, a moderate effect size, 80% power and 95% CI will be estimated, in a total of 46 patients. Considering a dropout of 20%, 56 patients should be recruited. ETHICS AND DISSEMINATION: The study was approved by the Universidade Federal de Juiz de Fora Teaching Hospital ethics committee and assigned the number 53058421.9.0000.5133 (version 3). The results will be disseminated via publications in peer-reviewed journals and presentations in medical meetings. TRIAL REGISTRATION NUMBER: RBR-6prps8g)/UTN U1111-1278-3224.

Revisiting the role of hyperbaric oxygen therapy in knee injuries: Potential benefits and mechanisms.

Knee injury negatively impacts routine activities and quality of life of millions of people every year. Disruption of tendons, ligaments, and articular cartilage are major causes of knee lesions, leading to social and economic losses. Besides the attempts for an optimal recovery of knee function after surgery, the joint healing process is not always adequate given the nature of intra-articular environment. Based on that, different therapeutic methods attempt to improve healing capacity. Hyperbaric oxygen therapy (HBOT) is an innovative biophysical approach that can be used as an adjuvant treatment post-knee surgery, to potentially prevent chronic disorders that commonly follows knee injuries. Given the well-recognized role of HBOT in improving wound healing, further research is necessary to clarify the benefits of HBOT in damaged musculoskeletal tissues, especially knee disorders. Here, we review important mechanisms of action for HBOT-induced healing including the induction of angiogenesis, modulation of inflammation and extracellular matrix components, and activation of parenchyma cells-key events to restore knee function after injury. This review discusses the basic science of the healing process in knee injuries, the role of oxygen during cicatrization, and shed light on the promising actions of HBOT in treating knee disorders, such as tendon, ligament, and cartilage injuries.

A oxigenoterapia hiperbárica veterinária integrada ao tratamento da necrose tecidual e osteomielite em cão: relato de caso / Veterinary hyperbaric oxygen therapy integrated to the treatment of tissue necrosis and osteomyelitis in a dog: case report

Na rotina veterinária, as lesões nas extremidades dos membros são constantes e representam um desafio especial pelas características anatômicas, susceptibilidade de exposição óssea e limitações de reparos e reconstruções quando comparado a outras regiões do corpo. A osteomielite, decorrente de mordeduras, tem alta prevalência e sua rápida evolução pode levar a medidas drásticas, como a amputação. Neste trabalho, é relatada a utilização da oxigenoterapia hiperbárica como terapia integrativa ao tratamento convencional e a avaliação de seus efeitos durante as 12 sessões realizadas em uma cadela vítima de mordedura, que apresentava necrose e exposição óssea com colonização por Staphylococcus sp e Pasteurella multocida. A avaliação evolutiva do quadro foi elaborada a partir de registro fotográfico da lesão, com escala, a cada três sessões e submetido à análise morfométrica por software analítico. A velocidade da marcha cicatricial revelou que a utilização desta terapia propiciou precocidade e efetiva atuação na cicatrização e no combate à osteomielite, evitando a amputação do restabelecendo as liberdades da paciente, contribuindo ao aprofundamento do emprego da oxigenoterapia hiperbárica na Medicina Veterinária.(AU)

In the veterinary routine, injuries in the extremities of the limbs are constant and represent a special challenge due to the anatomical characteristics, susceptibility of bone exposure and limitations of repairs and reconstructions when compared to other regions of the body. Osteomyelitis resulting from bites is highly prevalent and its rapid evolution can lead to drastic measures such as amputation. This work describes the use of hyperbaric oxygen therapy as an integrative therapy to conventional treatment and the evaluation of its effects during the 12 treatments performed in a female dog victim of a bite, that presented evolution to necrosis and bone exposure with colonization by Staphylococcus sp e Pasteurella multocida. The evolutionary assessment of the condition was elaborated from a photographic record of the lesion, with scale, every three treatments and submitted to morphometric analysis by analytical software. The speed of the healing gait demonstrated, that the use of this therapy proved precocity and effective action in healing and in the fight against osteomyelitis, avoiding the amputation of the limb, restoring the patient's freedoms. Thus contributing to the deepening on the use of hyperbaric oxygen therapy in veterinary medicine.(AU)

Eficacia y seguridad de la Oxigenoterapia Hiperbárica en el tratamiento de intoxicación por monóxido de carbono, oclusión de arteria central de la retina, Covid persistente, pérdida de audición súbita o encefalopatía post-anoxémica / Efficacy and safety of hyperbaric oxygen therapy in the treatment of carbon monoxide poisoning, central retinal artery occlusion, long Covid, sudden hearing loss and post-anoxic encephalopathy

La Oxigenoterapia Hiperbárica (HBOT) es una terapia no invasiva que pro duce un efecto revitalizador en todos los tejidos. Es un tratamiento médico defi nido como una inhalación intermitente de oxígeno al 100% en una cámara hiper bárica a una presión superior a 1,5 atmósferas absolutas. Su principal mecanismo de acción es la reducción del volumen de los gases en relación al incremento de la presión (Ley de Boyle-Mariotte) y el aumento de la presión parcial de oxígeno en los tejidos (leyes de Dalton y Henry). Las complicaciones de la HBOT son poco frecuentes y están relacionados con los cambios de presión y la toxicidad del oxígeno. Las más frecuentes son las lesiones por barotrauma. La solicitud de evaluación considera la HBOT en una serie de 15 patologías de las cuales, 10 fueron evaluadas en un informe previo, por lo que el presente informe se centra en evaluar la efectividad y seguridad de HBOT en el tratamiento de las siguientes 5 patologías: 1. Intoxicación por monóxido de carbono (CO). 2. Oclusión de la arteria central de la retina. 3. Covid persistente. 4. Pérdida de audición súbita. 5. Encefalopatía post-anoxémica. OBJETIVOS El objetivo es evaluar la eficacia, efectividad y seguridad de la HBOT en pacien tes con intoxicación por CO, oclusión de arteria central de la retina (CRAO), Covid persistente, pérdida de audición súbita (PAS) o encefalopatía post-anoxémica (EPA). 11 EFICACIA Y SEGURIDAD DE HBOT EN 5 INDICACIONES METODOLOGÍA Se ha llevado a cabo una revisión sistemática de los estudios científicos que evalúan la eficacia terapéutica del uso de la HBOT. Se llevó a cabo una búsqueda de guías clínicas, ensayos clínicos aleatorizados (ECA), revisiones sistemáticas (RS), meta-análisis (MA) e informes de evaluación en diferentes bases de datos (Medline, Embase, Cochrane Database, INAHTA Database), en bases de datos de Agencias de Evaluación de Tecnologías Sanitarias y en páginas web de ensayos clínicos. También se realizó una búsqueda manual a partir de las referencias de los estudios encontrados. Posteriormente, se procedió a realizar una lectura crítica de la literatura seleccionada y una extracción de los datos más importantes, así como una síntesis de la evidencia. RESULTADOS Intoxicación por CO Se incluyeron dos RS, una de calidad moderada-alta y otra de calidad baja. Ambas RS incluyeron estudios que comparaban la HBOT con la Oxigenoterapia normobárica (NBOT) o diferentes regímenes de HBOT. Los resultados de las dos RS no encontraron que la HBOT fuera superior a la NBOT. Oclusión de la arteria central de la retina (CRAO) Se han incluido dos RS que analizaba el efecto de HBOT en comparación con el control, una de calidad moderada-baja y otra de calidad críticamente baja. Los resultados no encontraron diferencias estadísticamente significativas en la mejora de agudeza visual (AV). Alguno de los estudios individuales concluye que el trata miento con HBOT podría mejorar la AV si se aplica de forma temprana. Covid Persistente Se incluyó un ECA con una calidad moderada-alta. Los resultados mostra ron diferencias estadísticamente significativas a favor de HBOT frente al grupo control en las variables de desempeño neurocognitivo y función ejecutiva, sínto mas psiquiátricos (depresión y somatización) y en los síntomas de interferencia del dolor y la fatiga. Pérdida de audición súbita (PAS) Se incluyeron 5 RS, dos mostraron una calidad metodológica alta y otras tres moderada. Una de las RS analizaba la eficacia de HBOT comparado con un con trol, mientras que las otras cuatro RS analizaron la efectividad de HBOT en com binación con tratamiento médico (TM) y comparado con el TM solo. Se ha observado una gran heterogeneidad en la metodología seguida en los estudios incluidos por las RS, tanto en el tiempo de inicio del tratamiento y la rea lización de los audiogramas tras la terapia, como diferencias en los comparadores. También se han observado diferencias en la gravedad de la pérdida de audición en los participantes incluidos por los diferentes estudios. Solo una de las RS inclui das analizó la eficacia del HBOT sola frente a otros tratamientos. Esta RS informó que la intervención con HBOT resultaba en un mayor número de pacientes con una ganancia igual o mayor del 25% de audición en comparación con el grupo control. Sin embargo, los autores indican que debido al pequeño número de participantes y la baja calidad de los estudios, estos resultados deben tomarse con cautela. Por otro lado, los autores también observaron una mayor mejora en la media de audio metría de tonos puros (ATP) en los participantes que recibieron HBOT frente a los que recibieron vasodilatadores, así como una mayor mejora en la audición, medida en decibelios (dB), de pacientes con PAS que recibieron HBOT en comparación con el grupo control. En el caso de las 4 RS que analizaron la eficacia de HBOT combinado con TM, tres de ellas estudiaron la eficacia de HBOT más esteroides comparado solo con el tratamiento con esteroides, los resultados indicaron que la adición de HBOT podría mejorar la audición en PAS grave y profunda. Por último, una RS analizó la eficacia del tratamiento de rescate con HBOT en pacientes con PAS refracta rios, no observando diferencias estadísticamente significativas entre añadir HBOT al tratamiento con esteroides. Encefalopatía post-anoxémica (EPA) No se han identificado estudios con comparador o RS que analizaran la efi cacia de HBOT en EPA. CONCLUSIONES Intoxicación por CO • La HBOT es menos efectiva que la NBOT en la mejora del dolor de cabeza y la incidencia de la fatiga. • La HBOT parece ser superior en algunas subescalas neuropsicológicas y en la valoración neuropsicológica flobal en comparación con NBOT. Oclusión de la arteria central de la retina (CRAO) • La HBOT puede mejorar la agudeza visual frente a la NBOT. Covid Persistente • La HBOT es superior a NBOT en la mejora del desempeño neurocogni tivo y la función ejecutiva. • La HBOT mejora la calidad de vida en los dominios de limitación física y energía en comparación con NBOT. • La HBOT mejora la depresión, su somatización, la interferencia del dolor y los trastornos del sueño en puntuación global del PSQI. Pérdida de audición súbita (PAS) Dado el pequeño tamaño muestral de los estudios primarios incluidos en las RS analizadas, la heterogeneidad en el régimen de HBOT en los regímenes de tratamiento aplicado y el alto riesgo de sesgo de los estudios primarios no se puede obtener una conclusión robusta sobre la eficacia y seguridad de la HBOT en el tra tamiento de la PAS. Encefalopatía post-anoxémica (EPA) La revisión sistemática no ha permitido identificar estudios comparativos que permitan obtener conclusiones sobre la efectividad y seguridad del tratamiento con HBOT en pacientes con EPA. Con la evidencia disponible no puede considerarse la HBOT como un único tratamiento de primera línea en las patologías estudiadas. Hace falta evidencia robusta de la eficacia específica de la HBOT sobre algu nas de estas enfermedades, combinada con otros tratamientos a través de estudios de calidad, para poder concluir claramente que es una terapia co-adyuvante efec tiva para las indicaciones evaluadas.

INTRODUCTION Hyperbaric Oxygen Therapy (HBOT) is a non-invasive therapy that produces a revitalising effect on all tissues. It is a medical treatment defined as an intermit tent inhalation of 100% oxygen in a hyperbaric chamber at a pressure greater than 1.5 absolute atmospheres. Its main mechanism of action is the reduction of gas volume in relation to the increase in pressure (Boyle-Mariotte's law) and the increase of oxygen partial pres sure in the tissues (Dalton's and Henry's laws). Complications of HBOT are rare and are related to pressure changes and oxy gen toxicity. The most frequent adverse events are barotraumatic damages. The evaluation request considers HBOT in 15 conditions of which 10 were evaluated in a previous assessment report, so the present report focuses on assess the effectiveness and safety of HBOT in the treatment of the following 5 conditions: 1. Carbon monoxide poisoning. 2. Central retinal artery occlusion. 3. Long Covid. 4. Sudden hearing loss. 5. Post-anoxemic encephalopathy. OBJECTIVE The objective is to evaluate the efficacy, effectiveness and safety of HBOT in patients with carbon monoxide poisoning, central retinal artery occlusion, Long Covid, sudden hearing loss or post-anoxemic encephalopathy. METHODS A systematic review (SR) of scientific studies evaluating the therapeutic effi cacy and effectiveness of HBOT was carried out. A search of clinical guidelines, randomised clinical trials (RCTs), systematic reviews, meta-analyses and evalu ation reports was carried out in different databases (Medline, Embase, Cochrane Database, INAHTA Database), in Health Technology Assessment Agencies data bases and on clinical trial websites. A manual search was also carried out based on the references of the studies found. Subsequently, a critical reading of the selected literature and an extraction of the most important data, as well as a synthesis of the evidence, was carried out. RESULTS Carbon monoxide poisoning Two SR were included, one of high and one of low quality. Both SRs included studies comparing HBOT with NBOT or different HBOT regimes. The results of the two SRs did not find HBOT to be superior to NBOT. Central retinal artery occlusion Two SR that analysed the effect of HBOT compared to control have been included, one of moderate-low quality and one of critically low quality. The results found no statistically significant difference in visual acuity (VA) improvement. Some of the individual studies concluded that HBOT treatment could improve VA if applied early. Long Covid One RCT with moderate high quality was included. The results showed statis tically significant differences in favour of HBOT versus the control group on neu rocognitive performance and executive function variables, psychiatric symptoms (depression and somatization) and on interfering symptoms of pain and fatigue. Sudden Hearing Loss (SHL) Five SR were included, two showed high and three moderate methodologi cal quality. One of the SR analysed the efficacy of HBOT compared to a control, while the other four SR assessed the effectiveness of HBOT in combination with medical treatment and compared to medical treatment alone. A great heterogeneity has been observed in the methodology followed in the studies included in the SRs, both in terms of time of treatment initiation, perfor mance of audiograms after therapy, and differences in comparators. Differences were also observed in the severity of hearing loss in the participants included in the different studies. Only one of the included SRs analysed the efficacy of HBOT alone versus other treatments. This SR reported that HBOT intervention resulted in a higher number of patients with a gain equal to or greater than 25% compared to the control group. However, the authors indicate that due to the small number of participants and the low quality of the studies, these results should be taken with caution. On the other hand, the authors also observed a greater improvement in mean pure tone audiometry in participants who received HBOT versus those who received vasodilators, as well as a greater improvement in hearing measured in decibels (dB) in SHL patients who received HBOT compared to the control group. For the 3 SRs that looked at the efficacy of steroid plus HBOT versus ster oid alone, the results indicated that the addition of HBOT could improve hearing in severe and profound SBP. Finally, an SR assessed the efficacy of HBOT relapse therapy in patients with refractory SHL, observing no statistically significant dif ference between adding HBOT to steroid therapy. Post-anoxemic encephalopathy No studies with comparator or SR that analysed the efficacy of HBOT in Post-anoxemic encephalopathy have been identified. CONCLUSIONS Carbon monoxide poisoning • HBOT is less effective than NBOT in improving headache and the inci dence of fatigue. • It appears to be superior in some neuropsychological subscales and in glo bal neuropsychological assessment compared to NBOT. Central retinal artery occlusion • HBOT may improve visual acuity compared to NBOT. Long Covid • HBOT is superior to NBOT in improving neurocognitive performance and executive function. • HBOT improves quality of life in the domains of physical limitation and energy compared to NBOT. • HBOT improves depression, its somatization, pain interference and sleep disorders in PSQI global score. Sudden hearing loss (SHL) The small sample size of the primary studies included in the analysed SR, the heterogeneity in the HBOT regimen applied and the high risk of bias of the pri mary studies do not allow a robust conclusion on the efficacy and safety of HBOT in the treatment of SHL. Post-anoxemic encephalopathy The systematic review has not identified any comparative studies that allow conclusions to be drawn on the effectiveness and safety of treatment with HBOT in patients with post-anoxemic encephalopathy. On the basis of the available evidence, HBOT cannot be considered as a sin gle first-line treatment in the studied conditions. Robust evidence of the specific efficacy of HBOT on some of these diseases, combined with other treatments through high-quality studies, is needed to be able to clearly conclude that it is an effective co-adjuvant therapy for the assessed conditions.