Fibromyalgia is a polysymptomatic central sensitisation disorder characterised by widespread pain, fatigue, sleep disturbances and neuropsychiatric features. Hyperbaric oxygen therapy modulates neuroinflammation, mitochondrial function and neuroplasticity, thereby yielding analgesic and functional benefits. Evaluate the efficacy and optimal timing of hyperbaric oxygen therapy as an adjunct to standard care for fibromyalgia. This single-centre, randomised, cross-over group, assessor-blinded clinical trial was conducted in the Department of Rheumatology at the University Hospital of the Federal University of Juiz de Fora, Juiz de Fora, Brazil, and adhered to Consolidated Standards of Reporting Trials (CONSORT) guidelines. Women (18-70 years) with a diagnosis of fibromyalgia for ≥2 years were randomised 1:1 to early hyperbaric oxygen therapy plus standard care or standard care alone (delayed group). Intention-to-treat (ITT) analysis was conducted with all 56 participants (mean age: 51.0±9.8 years; mean body mass index: 30.5±5.1 kg/m²). Standardised care (education, exercise and pharmacotherapy) plus hyperbaric oxygen therapy was delivered at 2.3 atmospheres absolute for 90 min, five times per week, over 8 weeks (total 32-40 sessions). The early group received hyperbaric oxygen therapy during weeks 0-8, while the delayed group received it during weeks 8-16, following the same protocol. Primary endpoints included the Fibromyalgia Impact Questionnaire-Brazilian Portuguese (FIQR-Br), the pain visual analogue scale (VAS) and the Symptoms Assessment Scale-40 (EAS-40) for psychopathology. Secondary endpoints included the 12-Item Short-Form Health Survey (SF-12) physical and mental components and adverse effects. Assessments were conducted at baseline, 8 weeks and 16 weeks, and analysed using a mixed-design 2×3 analysis of variance (group: early vs delayed; time: baseline, 8 weeks and 16 weeks) with Greenhouse-Geisser corrections as needed, followed by Bonferroni post hoc tests. Missing data were assessed using Little's missing completely at random (MCAR), and considering the ITT analysis, the means imputed for missing data were estimated through expectation maximisation. Effect sizes were reported as partial η² and Cohen's d with α=0.05. 44 participants completed the study, and the overall withdrawal rate was 21.4% with no baseline between-group differences. Significant time effects were observed for all primary outcomes and the SF-12 outcome (p<0.001; η²=0.23-0.60). Group×time interactions were significant for FIQR-Br, VAS, EAS-40 and SF-12 physical and mental (p≤0.02; interaction η² up to 0.23), indicating improvements during active hyperbaric oxygen therapy exposure. Compared with standard care alone over 8 weeks, combined treatment achieved greater gains: FIQR-Br, -31.1% vs -14.4%; VAS, -54.0% vs -33.5%; EAS-40, -28.4% vs -3.7%; SF-12 physical, +39.1% vs +14.8%; SF-12 mental, +57.4% vs +31.9%. Large within-group effect sizes were observed (eg, VAS d=2.5-2.7; FIQR-Br d=1.4-1.7). Efficacy was equivalent regardless of time started, and the benefits converged by the end of each hyperbaric oxygen therapy phase. After stopping hyperbaric oxygen therapy, the FIQR-Br and SF-12 mental component scores regressed towards standard care levels, whereas residual improvements persisted for up to 8 weeks in VAS, EAS-40 and SF-12 physical component scores. Adverse events were infrequent; one case of otalgia required extended management. Withdrawals were primarily due to non-compliance or intolerance to chamber confinement. No serious or unexpected safety concerns were reported. Hyperbaric oxygen therapy, delivered under a standardised protocol, is an effective and well-tolerated adjunct to multimodal fibromyalgia care. Timing can be individualised: early initiation for rapid relief or stepped introduction after optimised usual care, with comparable overall efficacy. The durability of the benefit appears to be exposure dependent, and maintenance or booster schedules merit further evaluation. RBR-6prps8g.
Pulmonary vein isolation (PVI) is an established rhythm-control therapy for atrial fibrillation (AF), yet the electrophysiological response of post-PVI individuals exposed to hyperbaric environments remains undocumented. Similarly, the in-vivo performance of implantable loop recorders (ILRs) and external patch-based electrocardiographic (ECG) devices under increased ambient pressure has never been reported. We describe the first hyperbaric electrophysiology assessment in a post-PVI diver undergoing both underwater immersion and dry hyperbaric exposure with dual-modality cardiac rhythm monitoring. A 46-year-old experienced diver with successful PVI underwent: a scuba dive to 42 m in a warm water pool, monitored with a marinised 12-lead ECG Holter system; and a stepwise hyperbaric chamber compression to 284 kPa (2.8 atmospheres absolute) in ambient air, with single-lead surface ECG recordings obtained at static pressure plateaus. In both cases, the subject was monitored as well by his ILR. No AF recurrence or other dysrhythmias were detected during either exposure, with stable heart rate trends. The ILR maintained full functional integrity after both the 42 m dive and the 284 kPa chamber compression. The external ECG patch yielded interpretable tracings during static phases. Telemetry failed due to electromagnetic shielding by the steel chamber walls. This case suggests that carefully selected post-PVI individuals may tolerate controlled underwater and hyperbaric exposure without rhythm destabilisation. Both implantable and external monitoring devices preserved operational integrity under moderate hyperbaric conditions, providing a foundation for the emerging field of hyperbaric electrophysiology monitoring and informing fitness-to-dive assessment in post-ablation patients.
Background/Objectives: Diving exposure can cause auditory injury involving both the middle and inner ear structures. Inner ear barotrauma (IEB) and inner ear decompression sickness (IEDCS) are the major inner ear disorders and frequently present with auditory and vestibular symptoms. This study examined how diving characteristics relate to patterns of auditory trauma. Methods: A retrospective chart review of 30 patients, with 36 affected ears, was performed. Diving depth, clinical manifestations, and treatment responses were analyzed to identify factors influencing related prognosis. Results: Diving depth was an important factor associated with symptom severity and the type of injury. Dives deeper than 30 m of seawater were linked to a higher incidence of sudden sensorineural hearing loss and vertigo. In contrast, transient symptoms with minimal objective abnormalities were typically observed in shallow dives. Patients with concomitant decompression sickness (DCS) showed poorer auditory and vestibular recovery following hyperbaric oxygen therapy, while those without DCS showed better hearing improvement. Vertigo was observed in 80% of IEB cases and 66.7% of IEDCS cases. Hearing recovery appeared to be more frequently observed in cases presenting with middle ear symptoms, suggesting a relatively favorable prognosis for IEB compared with IEDCS. Conclusions: The findings suggest potential associations between diving depth and DCS, and its involvement may play a role in the severity and prognosis of diving-related inner ear injury. IEB appeared to be associated with more favorable auditory outcomes compared with IEDCS; however, this observation should be interpreted with caution due to potential diagnostic uncertainty. Given the descriptive nature of the study, further studies with larger cohorts are needed to refine prognostic indicators and optimize management strategies.
Background/Objectives: Central retinal artery occlusion (CRAO) is a vision-threatening condition with limited evidence-based treatment options. Hyperbaric oxygen therapy (HBOT) has emerged as a potential intervention, but its efficacy remains debated. This systematic review and meta-analysis evaluated the therapeutic efficacy and safety of HBOT in CRAO. Methods: Relevant studies were identified across seven databases using optimized Boolean and MeSH-based strategies. Eligible studies evaluated HBOT in CRAO and reported visual or safety outcomes. Extracted data included demographics, intervention details, treatment timing, visual acuity outcomes, and adverse events. Risk of bias was assessed using ROBINS-I. Visual acuity outcomes were standardized to logMAR whenever directly reported or convertible, and subgroup analyses were stratified by HBOT initiation time (<12 h vs. >12 h), study type, and baseline visual severity when reported. A random-effects model was used, and pooled estimates were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Results: Twelve studies were included. The pooled efficacy analysis favored HBOT (OR = 0.47; 95% CI: 0.26-0.87; p = 0.02), although heterogeneity was substantial (Tau2 = 0.64; I2 = 78%). Stratified synthesis showed that studies in which HBOT was initiated within 12 h consistently reported greater visual improvement, whereas delayed or variably timed treatment showed attenuated and inconsistent benefits. After outcome harmonization, studies reporting logMAR-compatible data generally demonstrated clinically relevant visual improvement, while adverse-event rates did not differ significantly between HBOT and non-HBOT groups (OR = 0.70; 95% CI: 0.43-1.16; p = 0.17; I2 = 0%). Conclusions: HBOT appears most beneficial when initiated early, particularly within the first 12 h. However, heterogeneity in treatment timing, study design, and baseline severity reporting limits the certainty of these results and supports the need for standardized outcome reporting and protocol-driven prospective studies.
Hyperbaric oxygen therapy (HBOT) has been proposed as a treatment for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), but evidence remains limited. This study evaluated its clinical effectiveness and feasibility, as well as associated functional brain changes. Thirty patients with ME/CFS (mean age 42.3 ± 11.7 years; 7 males, 23 females) received 40 HBOT sessions. Clinical outcomes were assessed at baseline, during treatment, and four weeks post-treatment. The primary outcome was change in the physical functioning subscale of the Short Form-36 Health Survey (SF-36 PF). Secondary outcomes included severity of core symptoms assessed via questionnaires, exercise capacity, handgrip strength, cognitive performance, orthostatic intolerance, and brain magnetic resonance imaging (MRI; volumetry and functional connectivity [FC]). Thirty age- and sex-matched healthy controls (mean age 42.3 ± 11.3 years; 7 males, 23 females) were included for MRI comparison. SF-36 PF significantly improved during HBOT compared with baseline (g = 0.71, p = 0.006). SF-36 pain (p = 0.002, g = 0.79) and Chalder Fatigue Scale also showed clinically meaningful reductions (p < 0.001, g = -0.87). Exercise capacity (g = 0.66), muscle strength (g = 0.40), and information processing speed (g = 0.52) improved significantly after treatment (all p < 0.05). Treatment adherence was high and tolerability was favorable, with no major adverse events reported. Functional MRI analyses revealed increased thalamic FC in ME/CFS patients compared to healthy controls in bilateral sensorimotor (p < 0.001, t = 5.65, FDR-corrected) and visuo-occipital regions (p < 0.001, t = 5.40, FDR-corrected) at baseline. Following HBOT, thalamic hyperconnectivity shifted toward patterns observed in healthy controls. Responders, defined as a ≥ 10 points increase in SF-36 PF, showed greater reductions in thalamic hyperconnectivity than non-responders (p < 0.001, t = -4.34 to -5.18, FDR-corrected). HBOT was well tolerated and associated with significant improvements in physical functioning, fatigue, pain, and cognitive performance in ME/CFS. The post-treatment shift in thalamocortical connectivity toward healthy control patterns and its association with clinical response support the hypothesis that functional thalamic dysregulation contributes to ME/CFS pathophysiology and may be modulated by HBOT. This provides a network-level rationale for controlled trials to confirm therapeutic efficacy. ClinicalTrials.gov NCT06118138. Registered 01 November 2023 - Retrospectively registered, https://clinicaltrials.gov/study/NCT06118138?cond=ME%2FCFSamp;term=HBOTamp;rank=1 .
Military deep divers experience extreme environmental stressors, particularly with prolonged diving. Alterations such as hyperbaric conditions and variable O2 levels can prompt systemic/local oxidative stress (OxS) and elevated nitric oxide (NO.) post-dive release, heightening the risk of inflammation and cardiovascular events. Yet, deep diving (e.g. saturation diving) can also lead to cognitive impairment, whose mechanisms remain largely elusive but relevant to determine. Three Deep Divers (Italian Navy-Comsubin), with an average age of 31.00 ± 2.64 years, carried out a technical surface-supplied bounce diving in open water (-89m) in the Mediterranean Sea. From them, we collected saliva and urine samples before diving (T0), after deep diving followed by water-surface decompression (T1), and after complete subemersion (T2). To assess for pro-inflammatory and stress conditions, we evaluated reactive oxygen species (ROS) production, DNA oxidation (8-OHdG), total antioxidant capacity (TAC), nitric oxide (NO.) oxidation products, and the levels of interleukin-6, cortisol, brain-derived neurotrophic factor (BDNF), dopamine, and glutamate. At T1, ROS production increased (+ 121%) and continued to increase just to T2, coupled to a continuous rise in 8-OHdG, and a contemporary decline in TAC. Simultaneously, cortisol levels increased while those of dopamine decreased (-27%). BDNF levels were also sizably elevated (+ 175%). Conversely, no changes in pro-inflammatory markers and NO concentrations were evident. Oxidative stress and neurotransmitter increase and/or decrease (according to biomarkers evaluated) occur post-deep diving, suggesting preventative strategies to mitigate cognitive impairment.
Simulated diving and decompression can impair endothelial function, but the upstream oxidant sources and their relationship with endothelial nitric oxide synthase (eNOS) coupling in the pulmonary circulation remain unclear. We investigated whether NADPH oxidase 2 (NOX2) is associated with oxidative stress, tetrahydrobiopterin (BH4) depletion, altered eNOS coupling, and pulmonary endothelial dysfunction after simulated air diving. Eighteen male Sprague-Dawley rats were assigned to three groups: control, decompression stress, and decompression stress with the NOX2 inhibitor GSK2795039 (100 mg/kg, intraperitoneal) administered before pressurization. Decompression stress was induced by hyperbaric exposure to 600 kPa for 1 h followed by decompression to ambient pressure; pulmonary arteries were collected 1 h after decompression. We evaluated NOX2 expression, oxidative stress indices, BH4 content, eNOS phosphorylation and dimer/monomer ratio, nitric oxide metabolites (nitrate plus nitrite), markers associated with endothelial activation, and vasoreactivity. Compared with controls, decompression stress increased NOX2 expression, reactive oxygen species and lipid peroxidation, decreased superoxide dismutase activity, reduced BH4 and nitric oxide metabolites. It also caused a shift in eNOS towards a lower dimer/monomer ratio, increased endothelin-1 and adhesion molecules, and impaired endothelium-dependent relaxation, though endothelium-independent relaxation remained intact. GSK2795039 pretreatment attenuated oxidative stress, improved BH4 availability, restored nitric oxide metabolites, and decreased markers of endothelial activation, partially improving endothelium-dependent relaxation. These findings suggest that NOX2-associated oxidative stress contributes to reduced BH4 availability and eNOS coupling imbalance, leading to pulmonary endothelial dysfunction after decompression.
Unlike traditional hyperbaric oxygen treatment, which involves the inhalation of 100% oxygen by individuals enclosed in a pressurized treatment chamber at greater than sea level, mild hyperbaric oxygen treatment is performed in a pressurized chamber using shallower treatment depths and lower oxygen concentrations. This narrative review examines the physiological differences between mild and traditional hyperbaric oxygen treatment, the clinical uses of mild hyperbaric oxygen treatment, and the safety considerations of both treatment modalities. The systemic hyperoxia induced by traditional hyperbaric oxygen treatment promotes wound healing but is associated with adverse events, including oxygen free radical damage. Mild hyperbaric oxygen treatment may benefit peripheral microcirculation, parasympathetic activity, and metabolism but has not been studied extensively as a wound treatment modality. Due to the lower oxygen concentrations used in mild hyperbaric oxygen treatment, the risk of oxidative damage may be lower with this treatment than with traditional hyperbaric oxygenation. However, both mild and traditional hyperbaric oxygenation are associated with potentially life-threatening adverse events, including chamber explosion and/or fire. Careful adherence to safety standards may reduce the occurrence risk of such incidents, but compliance with those standards is not universally mandated and may vary among facilities. Traditional and mild hyperbaric oxygen treatment differ in physiology and clinical uses. Both treatments are associated with significant risks, but adherence to safety standards may reduce the incidence of adverse events and optimize patient care.
Bipolar disorder is a recurrent psychiatric condition characterised by episodic mood disturbances, residual functional impairment, and high rates of psychiatric and medical comorbidity. While many individuals achieve symptomatic remission, persistent deficits in cognition, emotional regulation, and insight may remain, raising concerns for participation in safety-critical activities such as scuba diving. This systematic review synthesised evidence from psychiatric, occupational, aviation, and diving medicine literature to examine the clinical course of bipolar disorder, treatment considerations, functional outcomes, and safety-relevant factors pertinent to fitness-to-dive assessments. Bipolar disorder exhibits marked heterogeneity in syndromal and functional outcomes. Even during euthymia, subtle impairments in attention, executive functioning, and decision-making may persist. Pharmacological stability is essential for diving, but treatment regimens, particularly lithium use, polypharmacy, and antidepressant therapy, introduce additional considerations. Comorbidity, circadian disruption, sleep deprivation, and reduced insight during early relapse further complicate risk assessment. Empirical data on diving outcomes in individuals with bipolar disorder are scarce, necessitating reliance on expert opinion and extrapolation from related safety-critical domains. Fitness-to-dive assessments in bipolar disorder should prioritise sustained functional stability, reliable treatment adherence, and illness insight over symptom absence alone. A cautious, individualised approach is warranted, incorporating medication effects, comorbidity, operational context, and relapse-prevention planning, supported by collaboration between mental health professionals and diving medical examiners.
Professional divers work in safety-critical environments that require sustained attention, rapid judgment, and stable emotional control. Neuroticism is a vulnerability trait related to negative affectivity, perceived stress reflects appraisal of recent demands, and psychological resilience may be associated with weaker stress-related associations. This study examined how these factors were associated with pre-dive state anxiety in professional divers. This cross-sectional study used a de-identified, code-linked, two-component survey design in China from January to February 2026. A total of 300 professional divers completed the baseline web-based questionnaire, and 277 were included in the final analysis after eligibility and data-quality screening. The baseline questionnaire assessed demographic characteristics, neuroticism, perceived stress, and psychological resilience. The State scale of the State-Trait Anxiety Inventory (STAI-S) was completed separately on the day of a scheduled diving task, shortly before the dive. Pearson correlations, adjusted linear regression models, and exploratory interaction analyses were conducted controlling for age, education, and years of diving experience. Neuroticism was positively correlated with state anxiety (r = 0.77, p < 0.001) and perceived stress (r = 0.29, p < 0.001), whereas resilience was negatively correlated with neuroticism (r = -0.49, p < 0.001) and state anxiety (r = -0.58, p < 0.001). After adjustment, neuroticism was strongly associated with state anxiety (B = 0.81, SE = 0.04, β = 0.78, p < 0.001), and perceived stress was also associated with state anxiety after accounting for neuroticism (B = 0.16, SE = 0.05, β = 0.13, p = 0.001). Resilience did not significantly moderate the direct neuroticism-state anxiety association (B ≈ 0.000, p = 0.837), but it moderated the neuroticism-perceived stress and perceived stress-state anxiety associations (both B = -0.011, p < 0.001). These associations were weaker at higher resilience. In this convenience sample of Chinese professional divers, higher neuroticism and perceived stress were associated with higher pre-dive state anxiety, whereas greater resilience was associated with lower state anxiety and with weaker selected stress-related associations. The mean STAI-S score was in a low-to-moderate range; therefore, the findings should not be interpreted as showing clinically elevated anxiety or as implying that all pre-dive arousal is maladaptive. Longitudinal and repeated-measures studies are needed to clarify temporal ordering, practical significance, and intervention implications.
During clinical use of extracorporeal membrane oxygenation (ECMO) in hyperbaric conditions at our centre, upward titration of indicated sweep gas flow rates is required to maintain adequate CO₂ clearance. This project measured the impact of hyperbaric pressure on oxygen flow rates delivered by the Comweld Ezi-Flow flowmeters used in our centre. Oxygen flow rates through Comweld Ezi-flow standard and low oxygen gas flowmeters were set at 101.3 kPa (1 atmosphere absolute [atm abs]) and then measured at intervals up to 284 kPa (2.8 atm abs) using a calibrated gas flow analyser, with cross verification against a small Douglas bag test type apparatus. During testing, the chamber was compressed and decompressed at a rate of 10 kPa·min⁻¹. Flow rates during chamber compression and decompression were compared. The indicated rate of oxygen gas flow through the unadjusted flowmeters changed minimally - typically rising by a maximum of half of the diameter of the indicator ball. The actual (volumetric) flow, tested across indicated flow rates from 3 to 12 L·min⁻¹, was consistently reduced by approximately 50% as the chamber pressure increased from 101.3 to 284 kPa (1 to 2.8 atm abs). A slightly smaller reduction was observed when assessing the low flowmeter across the same pressure range; reductions of 40.0 and 43.3% were demonstrated at 0.3 to 0.6 L·min⁻¹ respectively. Differences in flow rates between compression and decompression were minor except at the very lowest flows. At 284 kPa (2.8 atm abs), actual volumetric flow of oxygen through Comweld Ezi-Flow flowmeters is dramatically reduced and this needs appropriate compensation to ensure therapeutic aims are achieved.
Technical diving, involving rebreathers and/or helium-based gas mixtures for deeper and longer dives, may influence risk and clinical presentation of injuries due to helium's properties, equipment constraints, or exposure conditions. This study aims to describe the specific characteristics of this accidentology. A retrospective study was conducted across five French coastline hyperbaric units. Medical records of technical divers presenting with decompression sickness (DCS), immersion pulmonary oedema (IPO), or gas-toxicity between 2010 and 2024 were reviewed. 127 technical divers were included, three declined participation, leaving 124 cases for analysis. DCS was the most frequent condition (n = 105) followed by IPO (n = 16) and gas toxicity (n = 3). Median age was 45 [IQR 37-53] years, and 113 (91%) were male. Rebreathers were used in 94 (75.8%) cases and helium-based mixtures in 77 (62%). Previous diving-related accidents were reported in 36 (29%) cases. IPO occurred mainly after shallower dives in wetsuits and was frequently associated with procedural errors. Among DCS cases isolated musculoskeletal DCS predominated (n = 36), whereas spinal involvement was less frequent. When indicated, median recompression delay was 238 [IQR 135-555] minutes. Unfavourable outcomes occurred in 26 (25%) DCS cases, primarily with bone or inner-ear involvement. Technical diving accidents exhibit distinct patterns from recreational diving, notably greater musculoskeletal involvement and a possible increased risk of dysbaric osteonecrosis (DON). Current evidence does not support different management, but the risk of potential initially silent bone lesions should not be overlooked. Further research on helium-related risks and hyperbaric treatment's role in DON prevention is needed.
The Divers Alert Network (DAN) aims to provide safety information for all types of diving. Assessing the number of active closed-circuit rebreather (CCR) divers is difficult, as pertinent information is often not available. This review aims to give an overview of global use and safety of CCR diving equipment from 2013-2022. Data were combined and assessed from various DAN internal and public sources on CCR diver demographics, fatalities, and CCR sales. Over the past 10 years, the number of certified CCR divers has increased from an estimated 2,000 in 2013, to 3,000 in 2022. There has been an increase in growth in CCR sales over a five-year period from 2018, with around 25,000 to 35,000 units on the market today; rebreather divers are a growing community. There were 241 confirmed CCR fatalities from 2013-2022, mean 24 (SD 6) per year. Most fatal accidents involved dives made between 40-80 m (130-260 ft) depth. Cause of death is difficult to establish due to lack of detail and dive-specific training for the medical examiner. The estimated death rate is 1.8-3.8 deaths per 100,000 CCR dives although these values are derived from limited data. Not enough information is made available to address CCR accident analysis effectively, perhaps stemming from family reticence to discuss the incident, fear of litigation, and/or lack of diving knowledge reducing the useful information. DAN continues to collect CCR data, but increased collaboration between training bodies, equipment providers, and comprehensive reporting of incidents is needed to reveal the true picture.
Ultrasound-guided regional anesthesia (UGRA) is an essential skill in anesthesiology, yet non-regional anesthesia fellowship-trained anesthesiologists often have limited opportunities to perform it. Using the Theoretical Domains Framework(TDF), we aimed to explore the barriers to and facilitators of anesthesiologists' performing UGRA without fellowship training in Canada. We conducted a qualitative study following ethics approval, using semistructured interviews with 15 Canadian staff anesthesiologists who did not complete a regional anesthesia fellowship. Interviews were audio-recorded, transcribed, and analyzed using NVivo 12 (QSR International, Burlington, MA, USA) with a deductive coding approach based on the TDF. We used predefined criteria to identify relevant TDF domains that influence the performance of ultrasound-guided regional anesthesia. We achieved data saturation by the 15th interview. Eight TDFdomains were identified as most relevant to performing UGRA. Key facilitators were institutional support and dedicated resources, training and practice opportunities, mentorship and teamwork, and confidence. Major barriers were lack of resources/staff/time, surgeon resistance, fear of complications/workflow disruption and provider anxiety, low confidence, and insufficient training/practice. Ultrasound-guided regional anesthesia adoption by non-regional anesthesia fellowship-trained anesthesiologists is influenced by a complex interplay of individual, social, and environmental factors. These findings highlight clear targets for implementation strategies, including more training, resource allocation, and strengthened interdisciplinary collaboration across departments such as anesthesia, surgery, and emergency medicine. Addressing these barriers and leveraging enablers through theory-informed interventions may increase UGRA uptake and ultimately lead to better perioperative patient care. RéSUMé: OBJECTIF: L’anesthésie locorégionale échoguidée est une compétence essentielle en anesthésiologie, mais les anesthésiologistes n’ayant pas effectué de fellowship en anesthésie locorégionale disposent souvent de peu d’occasions de la pratiquer. En nous appuyant sur le Cadre des domaines théoriques (CDT), nous avons cherché à explorer les obstacles et les facteurs facilitants associés à la pratique de l’anesthésie locorégionale échoguidée sans formation par fellowship au Canada. MéTHODES: Après avoir obtenu l’approbation éthique, nous avons mené une étude qualitative reposant sur des entretiens semi-structurés auprès de 15 anesthésiologistes en poste au Canada n’ayant pas complété de fellowship en anesthésie locorégionale. Les entretiens ont été enregistrés, transcrits et analysés à l’aide de l’outil NVivo 12 (QSR International, Burlington, MA, États-Unis) selon une approche de codage déductif fondée sur le CDT. Nous avons eu recours à des critères prédéfinis pour repérer les domaines du CDT les plus pertinents quant à la pratique de l’anesthésie locorégionale échoguidée. RéSULTATS: La saturation des données a été atteinte dès le 15e entretien. Huit domaines du CDT ont été recensés comme étant les plus pertinents pour la pratique de l’anesthésie locorégionale échoguidée. Les principaux facteurs facilitants étaient le soutien institutionnel et la disponibilité de ressources dédiées, les occasions de formation et de pratique, le mentorat et le travail d'équipe, ainsi que la confiance en soi. Les obstacles majeurs comprenaient le manque de ressources, de personnel et de temps, la résistance des chirurgiennes et chirurgiens, la crainte de complications et de perturbations du flux de travail, l’anxiété des prestataires de soins, le manque de confiance en soi et une formation ou une pratique insuffisante. CONCLUSION: L’adoption de l’anesthésie locorégionale échoguidée par des anesthésiologistes sans fellowship en anesthésie locorégionale est influencée par une interaction complexe de facteurs individuels, sociaux et environnementaux. Ces résultats mettent en évidence des cibles claires pour l'élaboration de stratégies de mise en œuvre, notamment l’amélioration de la formation, l’allocation de ressources et le renforcement de la collaboration interdisciplinaire entre les départements concernés, comme l’anesthésie, la chirurgie et la médecine d’urgence. La prise en charge de ces obstacles et l’optimisation des facteurs facilitants par des interventions fondées sur des modèles théoriques pourraient favoriser l’adoption de l’anesthésie locorégionale échoguidée et, à terme, améliorer la qualité des soins périopératoires.
Chronic fatigue syndrome (CFS) is frequently accompanied by persistent cognitive deficits and neuroinflammation, yet effective interventions remain limited. Here we tested whether hyperbaric oxygen (HBO) improves CFS-related cognitive impairment in mice and examined a glycerophospholipid-metabolic mechanism. CFS was induced by a 3-week multi-stressor paradigm, and mice received HBO (100% O2, 2.5 ATA, 60 min/session, 4 sessions/week for 3 weeks). HBO improved fatigue-/depressive-like behaviors and rescued spatial and recognition memory. Histology and ultrastructure analyses showed that HBO reduced hippocampal neuronal injury and preserved blood-brain barrier (BBB) integrity, accompanied by decreased pro-inflammatory cytokines and attenuated microglial activation. Untargeted LC-MS metabolomics revealed that HBO partially reversed CFS-associated metabolic shifts and enriched glycerophospholipid metabolism. Hippocampal Western blot further showed that HBO reduced CFS-associated elevation of PLA2G4A signaling. In parallel, PGE2 levels were decreased by HBO and by AACOCF3, supporting a PLA2G4A-related downstream inflammatory lipid mediator axis. In BV2 microglia and in vivo CFS mice, pharmacological PLA2G4A inhibition with AACOCF3 attenuated inflammatory and behavioral abnormalities, and subsequent HBO did not confer additional significant benefit. Together, these data support that HBO alleviates CFS-related cognitive impairment in this model, at least in part, through suppression of neuroinflammation involving a PLA2G4A-linked glycerophospholipid metabolic pathway.
Fitness-to-dive after otologic surgery is often approached conservatively, with some procedures historically labelled as absolute contraindications despite limited empirical evidence. The available literature is heterogeneous and includes clinical reports, experimental pressure studies, guidance documents, and manufacturer specifications, leading to uncertainty in clinical counseling. We aimed to characterise the available evidence regarding fitness-to-dive after otologic surgery and to develop an evidence-informed clinical decision aid. A scoping review was conducted in accordance with PRISMA-ScR guidance. PubMed/MEDLINE, Embase, Scopus, and relevant non-indexed sources were searched. Eligible sources included clinical reports and series, experimental or hyperbaric chamber studies, guidance or consensus documents, and manufacturer statements providing explicit pressure- or depth-related information. Data were charted descriptively by procedure type and evidence stream. The search identified 324 records; after removal of duplicates and screening, 40 sources were included. The evidence base was predominantly non-comparative. Across procedures, recommendations emphasised postoperative stability and reliable pressure equalisation rather than surgical history alone. Canal wall down mastoidectomy was consistently portrayed as incompatible with diving, whereas selected middle ear reconstructions and stapes surgery were commonly described as potentially compatible in appropriately selected individuals. For cochlear implantation, guidance was mainly conditional and based on hyperbaric testing, limited clinical diving reports, and manufacturer-specified pressure or depth limits. Communication emerged as an additional practical consideration in cases of significant hearing loss. Relevant evidence is limited and heterogeneous, and does not consistently support blanket prohibitions for all otologic procedures. A function-based, individualised approach is supported, while specific higher-risk scenarios warrant restriction. Prospective registries and standardised outcome reporting are needed to refine procedure-specific recommendations.
Hyperbaric oxygen treatment (HBO₂) uses increased atmospheric pressure and fractional oxygen to enhance tissue oxygen delivery. HBO₂ has gained attention as a tool for athletic recovery and performance, but past reviews in the literature are limited or inconclusive. This systematic review and meta-analysis aim to provide an update and assess the effect of HBO₂ on athletic recovery. Literature searches were performed across PubMed, Cochrane Central, Google Scholar, and Embase (January 1, 2015-September 15, 2024), following PRISMA guidelines. Studies included healthy athletes undergoing HBO₂ to assess athletic performance, metabolic recovery, and physiological responses. Quality assessment was performed using Cochrane's risk of bias tools (ROB2 and ROBINS-1). A meta-analysis with subgroup analyses by age, body mass index, and body fat mass percentage was conducted, along with a meta-regression examining HBO₂ protocol characteristics and outcomes. Eleven met the eligibility criteria; six studies were included in the meta-analysis. The meta-analysis showed that HBO₂ significantly reduced post-recovery blood lactate levels (effect size: -1.71; 95% CI: -3.10 to -0.32). Subgroup analysis revealed that younger athletes and those with lower fat mass receiving HBO₂ exhibited significant reductions in post-recovery lactate levels. Meta-regression was inconclusive but suggested treatment effect heterogeneity based on HBO₂ protocol characteristics. HBO₂ showed limited application in short-term power output and force production. Hyperbaric oxygen treatment is an efficient method for improving athletic performance, particularly by reducing post-exercise lactate levels, thereby supporting faster metabolic recovery. Future studies should focus on standardized protocols, diverse populations, and long-term outcomes to better understand HBO₂'s potential in orthopedics and sports medicine.
Hyperbaric oxygen therapy (HBOT) is widely used as a therapeutic intervention for various types of wounds. Studies have shown that in addition to improving local oxygen supply to the wound site, HBOT can also influence cytokine activity, promote the survival of tissue mesh, and thereby facilitate wound healing. Moreover, HBOT inhibits the growth and reproduction of various pathogenic bacteria and enhances the phagocytic capacity of leukocytes, effectively preventing and controlling infection. This case study involves a 61-year-old female diagnosed with invasive micropapillary carcinoma, who underwent a combination of treatments including radiotherapy, chemotherapy, immunotherapy, and targeted therapy. Nine years post-surgery, the patient experienced a recurrence of left breast cancer, accompanied by cancer wounds with exudate, edema, and ulceration in multiple areas such as the chest and back. Following comprehensive treatment consisting of anti-infective therapy, nutritional support, and edema management, along with three courses of adjuvant HBOT, the patient showed significant improvement in wound exudate and odor, resolution of lymphedema, and a reduction in wound volume, although the wound area did not show notable change. This study implemented a comprehensive care plan for patients with malignant wounds, including measures such as wound debridement, anti-infection treatment, nutritional support, and HBOT. Following the integrated intervention, symptoms including wound exudate, odor, and lymphedema were alleviated, and wound volume was reduced, although no significant change was observed in wound area. The primary benefit of HBOT in malignant wound management lies in symptom control, while its effect on structural wound healing appears limited. Its specific role within multidisciplinary comprehensive care requires further investigation.
Quantifying inert gas uptake and washout is critical for understanding decompression sickness (DCS). However, the limited amount of data has made it difficult to integrate inert gas kinetics into risk models for DCS. Measuring whole-body inert gas kinetics during submersion is technically challenging. This study presents a novel method for quantifying inert gas uptake and washout in human divers using a rebreather-based system. During constant-depth diving with a closed-circuit system that maintains a constant oxygen partial pressure, changes in buoyancy will reflect the kinetics of inert gas. Two divers completed four dives each, with a bottom phase at 2.5 bar and a decompression phase at 1.3 bar or 1.4 bar. Load cell data were converted into equivalent changes in volume of nitrogen standardised for temperature and pressure (VN₂, STP). Power analysis was conducted to quantify the resolution by which the method could detect nitrogen uptake and washout volumes. Distinct uptake and washout curves were obtained, comparable to previous studies using other techniques. Mean VN₂ uptake during the bottom phase was 0.96 L (SD 0.29), while mean washout during decompression was 0.67 L (SD 0.26). The minimal mean detectable difference (MDD) with eight dives was 0.28 L for the bottom phase and 0.26 L for the decompression phase, considering standard 80% power and a 0.05 significance level. This novel method quantifies inert gas kinetics during submersion with acceptable precision and accuracy. It could facilitate the collection of inert gas kinetics data during submersion, potentially yielding valuable correlations with the risk of DCS.
Hyperbaric oxygen (HBO) therapy involves the administration of 100% oxygen at elevated atmospheric pressure and has long been utilized for both therapeutic and prophylactic purposes. While early applications of HBO pretreatment primarily emphasized denitrogenation and denucleation to prevent decompression sickness in diving and aerospace settings, accumulating preclinical studies and clinical evidence now indicate that HBO pretreatment's broader protective effects are mediated by preconditioning. Central to this process is the generation of reactive oxygen species (ROS), which serve as critical signaling molecules that trigger adaptive cellular responses upon exposure to HBO. ROS induced by HBO activates key transcriptional regulators, including nuclear factor erythroid 2-related factor 2, heat shock factor 1, and hypoxia-inducible factor-1α, leading to the upregulation of protective proteins such as heme oxygenase-1, heat shock proteins, and vascular endothelial growth factor. These molecular responses enhance tissue resilience, promote cellular survival, and improve tolerance to ischemic, inflammatory, and oxidative injuries observed across diverse clinical conditions. This review focuses on HBO-induced protective proteins, synthesizing current knowledge of their molecular mechanisms, expression dynamics, and clinical relevance, as well as the role of exposure protocols in regulating their expression. The findings provide a framework for designing and interpreting future clinical applications of HBO preconditioning.