Hyperbaric Oxygen Therapy Group Research Articles

Hyperbaric oxygen therapy improves the efficacy of conventional supportive treatment for late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation

ABSTRACT Objective This study aims to investigate the efficacy and safety of hyperbaric oxygen therapy (HBOT) in the treatment of late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation. Methods This retrospective analysis included 16 patients with late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation between 2016 and 2022. Among them, 8 patients received HBOT in addition to conventional treatment, while the other 8 received only conventional treatment. The clinical efficacy and safety of HBOT were evaluated by comparing the Numeric Rating Scale pain scores and clinical grades of hematuria before and after treatment, reflecting the patients’ urinary pain and hematuria status. Results The patients were divided into two groups based on whether they received HBOT. The group that received HBOT (n = 8) had a shorter duration of illness compared to the non-HBOT group (n = 8) (p < 0.05). The time for the NRS to decrease to below 2 was also shorter in the HBOT group. Furthermore, the patients who received HBOT did not experience any significant adverse reactions. Conclusion The combination of conventional treatment and hyperbaric oxygen therapy (HBOT) has been shown to improve symptoms such as urinary pain, frequency, urgency, and hematuria in patients with late-onset hemorrhagic cystitis after transplantation. This approach has been proven to be safe and effective.

Hyperbaric oxygen therapy vs. pharmacological intervention in adults with fibromyalgia related to childhood sexual abuse: prospective, randomized clinical trial

Fibromyalgia syndrome (FMS) is a chronic pain syndrome characterized by disruptions in pain processing within the central nervous system. It exhibits a high prevalence among patients with a history of traumatic experiences, notably childhood sexual abuse (CSA). This study compared the efficacy of hyperbaric oxygen therapy (HBOT) to the current pharmacological standard of care for individuals suffering from CSA-related FMS. Forty-eight participants diagnosed with FMS and a history of CSA were randomly assigned to either the HBOT group (60 sessions of 100% oxygen at 2 ATA for 90 min, with air breaks every 5 min) or the medication (MED) group (FDA-approved medications, Pregabalin and Duloxetine). The primary endpoint was the Fibromyalgia impact questionnaire (FIQ) score, while secondary endpoints encompassed emotional status and daily functioning questionnaires, as well as pain thresholds and conditioned pain modulation tests. Brain activity was evaluated through single photon emission computed tomography (SPECT). Results revealed a significant group-by-time interaction for the FIQ score favoring HBOT over MED (p < 0.001), with a large effect size (Cohen's d = − 1.27). Similar findings were observed in emotional symptoms and functional measures. SPECT imaging demonstrated an increase in activity in pre-frontal and temporal brain areas, which correlated with symptoms improvement. In conclusion, HBOT exhibited superior benefits over medications in terms of physical, functional, and emotional improvements among FMS patients with a history of CSA. This associated with increased activity in pre-frontal and temporal brain areas, highlighting the neuroplasticity effect of HBOT.

The effects of hyperbaric oxygen therapy on snake-bite-associated wounds in dogs.

To assess the effect of hyperbaric oxygen therapy (HBOT) on Crotalinae envenomation-induced wound swelling and severity and pain in dogs, and to describe the safety and complications of HBOT. Prospective, randomized, controlled, blinded study (2017-2021). University teaching hospital, private veterinary practice. Thirty-six client-owned dogs presenting within 24hours of a confirmed or suspected naturally occurring Crotalinae snake bite injury were enrolled between 2017 and 2021. In addition to the standard of care treatment, dogs received 2 interventions with either HBOT (n=19) or control (n=16) within 24hours of hospital admission. Dogs receiving HBOT were pressurized over 15 minutes (1psi/min), maintained at a target pressure of 2 atmosphere absolute (ATA) for 30 minutes, and decompressed over 15 minutes. Control dogs received 1 ATA for 1hour. Local wound swelling, wound severity score, and pain score were assessed at admission, before and after each intervention, and at hospital discharge. There was no significant difference in wound swelling (P=0.414), severity score (P=1.000), or pain score (P=0.689) between HBOT and control groups. Pain decreased significantly over time regardless of the study intervention (P<0.001). There were no major adverse effects associated with either study intervention. HBOT did not significantly alter the short-term recovery from Crotalinae envenomation in this study population. However, the study might be underpowered to detect a significant treatment effect.

Would hyperbaric oxygen therapy be a supportive treatment method for refractory idiopathic granulomatous mastitis?

BackgroundRefractory IGM causes patients to use antibiotics, steroid therapy, immunosuppressive agents for a very long time and even leads to surgical procedures resulting in the loss of breast tissue. Hyperbaric Oxygen Therapy (HBOT) is a frequently used method in the treatment of wounds that are difficult to heal. We thought that HBOT would be an alternative treatment method for refractory IGM patients. MethodsIt is a retrospective cohort study on refractory IGM patients conducted at three tertiary care treatment centers between January 2021 and July 2023. The patients were evaluated in two groups: those who only took steroid treatment and those who received HBOT and steroid treatment. The demographic and clinical characteristics of the patients, the types of treatment applied and their responses to treatment were evaluated. ResultsThere were no significant differences generally in the demographic and clinical features in both groups. The incidence of multicentric GM was found to be higher in the HBOT group (66.67%; p = 0.044). Although the recovery results were similar in both groups, the average daily steroid dose and duration of drug use were found to be higher in the group receiving only steroid treatment (16 mg vs. 4 mg and 270 days vs. 30 days) (p<0.001). ConclusionIn our study, we showed for the first time in the literature that HBOT is effective in the treatment of refractory IGM patients. Our study needs to be supported by prospective studies evaluating cost effectiveness and possible long term complications..

Contemporary national outcomes of hyperbaric oxygen therapy in necrotizing soft tissue infections.

The role of hyperbaric oxygen therapy (HBOT) in necrotizing soft tissue infections (NSTI) is mainly based on small retrospective studies. A previous study using the 1998-2009 National Inpatient Sample (NIS) found HBOT to be associated with decreased mortality in NSTI. Given the argument of advancements in critical care, we aimed to investigate the continued role of HBOT in NSTI. The 2012-2020 National Inpatient Sample (NIS) was queried for NSTI admissions who received surgery. 60,481 patients between 2012-2020 were included, 600 (<1%) underwent HBOT. Primary outcome was in-hospital mortality. Secondary outcomes included amputation, hospital length of stay, and costs. A multivariate model was constructed to account for baseline differences in groups. Age, gender, and comorbidities were similar between the two groups. On bivariate comparison, the HBOT group had lower mortality rate (<2% vs 5.9%, p<0.001) and lower amputation rate (11.8% vs 18.3%, p<0.001) however, longer lengths of stay (16.9 days vs 14.6 days, p<0.001) and higher costs ($54,000 vs $46,000, p<0.001). After multivariate analysis, HBOT was associated with decreased mortality (Adjusted Odds Ratio (AOR) 0.22, 95% CI 0.09-0.53, P<0.001) and lower risk of amputation (AOR 0.73, 95% CI 0.55-0.96, P = 0.03). HBO was associated with longer stays by 1.6 days (95% CI 0.4-2.7 days) and increased costs by $7,800 (95% CI $2,200-$13,300), they also had significantly lower risks of non-home discharges (AOR 0.79, 95%CI 0.65-0.96). After correction for differences, HBOT was associated with decreased mortality, amputations, and non-home discharges in NSTI with the tradeoff of increase to costs and length of stay.

Effects of hyperbaric oxygen therapy on autistic behaviors and GRIN2B gene expression in valproic acid-exposed rats.

Autism is a complex neurodevelopmental condition characterized by deficits in social interaction, communication, and restricted repetitive behaviors. Hyperbaric oxygen therapy (HBOT) has emerged as a potential treatment for autism, although its effects on behavior and gene expression are not well understood. The GRIN2B gene, known for its involvement in encoding a glutamate receptor subunit crucial for neuron communication and associated with autism, was a focus of this study. Using a rat model induced by prenatal exposure to valproic acid, we examined the impact of HBOT on autism-like behaviors and GRIN2B gene expression. Male Wistar rats were categorized into four groups: control, VPA (valproic acid-exposed), VPA+HBOT [2 atmosphere absolute (ATA)], and VPA+HBOT (2.5 ATA). The rats underwent several behavioral tests to assess social behavior, anxiety, stereotype and exploratory behaviors, and learning. Following the behavioral tests, the HBOT groups received 15 sessions of HBOT at pressures of 2 and 2.5 (ATA), and their behaviors were re-evaluated. Subsequently, real-time PCR was employed to measure GRIN2B gene expression in the frontal lobe. Our results indicated that HBOT significantly increased social interaction and exploratory behaviors in VPA-exposed rats, alongside elevated GRIN2B gene expression in their frontal lobe. Our findings imply that HBOT might have a potential role in ameliorating autism-related behaviors in the VPA rat model of autism through potential modulation of GRIN2B gene expression. However, additional research is essential to fully comprehend the underlying mechanisms and refine the HBOT protocol for optimizing its effectiveness in improving autism-related symptoms.

(108) Evaluation the Efficacy and Safety of Hyperbaric Oxygen Therapy in Sildenafil Citrate Non Responder Organic Erectile Dysfunction Patients: a Randomized Double Blinded Controlled Clinical Trial

Abstract Introduction Although the phosphodiesterase 5 inhibitors (PDE5i) are the first-line oral agents for erectile dysfunction (ED) treatment, there is growing number of PDE5i- non responder patients. Management of those patients is challenging and one of the new suggested regenerative therapies is the hyperbaric oxygen therapy (HBOT). HBOT is the application of oxygen under pressure to increase tissue oxygen levels. Few clinical reports were published about HBOT and ED. Objective To evaluate the efficacy and safety of HBOT in sildenafil citrate non- responder organic ED patients. Methods The current study included 30 sildenafil citrate non-responder ED patients. Patients were divided into two groups (randomly assigned and comparably cross-matched for age). Both patients and the investigators were blinded as regards the treatment until the end of the study. Group 1: Patients assigned to the HBOT group (20 patients) were treated with (30) sessions in 5 days/week (90 minutes of 100% oxygen at 2.2 ATA); Group 2: Patients assigned to the control group (10 patients) were exposed to (30) sessions of air oxygen tension at 1 ATA with room oxygen. Baseline laboratory investigations were done (random blood sugar, lipid profile, total &amp; free testosterone). All patients were evaluated with the sexual health inventory for men (SHIM), erection hardness score (EHS), the sexual health encounter profile (SEP), and penile color Doppler initially, at 1 &amp; 3 months after the end of treatment. Results The age mean ± SD in the HBOT group was 56.35±7.43 years and in the control group was 61.7±7.14 years. The current study showed that sildenafil citrate non-responders ED patients with 30 sessions of HBOT in 5 days/week, demonstrated a significant improvement of the total SHIM score, EHS, and SEP after 1 month of stoppage of treatment as compared to the control group. Also, penile color Doppler evaluation showed a significant improvement of 10 &amp;20 minutes peak systolic velocity (PSV) between patients receiving HBOT compared to the control after 1 month of stoppage of treatment. More interestingly, the improvement of the total SHIM score, EHS, and SEP continued after 3 months of stoppage of the HBOT treatment as compared to the baseline evaluation. In addition, 10 &amp;20 minutes PSV with penile color Doppler evaluation demonstrated maintained improvement after 3 months of stoppage of the HBOT treatment as compared to the baseline evaluation. In addition, the linear regression analysis was done for factors affecting SHIM score improvement (1 month/baseline) in the HBOT treatment group, revealing that hypertension was an independent predictor for SHIM score improvement. Hypertensive patients showed 4.6 times more SHIM score improvement as compared to non-hypertensive patients. As regards HBOT safety, there was no significant difference in adverse effects between the HBOT treatment group and the control group. Conclusions HBOT might be a potential therapeutic modality for sildenafil citrate non-responder ED patients especially in hypertensive patients with good safety profile. Further a multi-centric trial with a larger sample size and a longer follow-up period is recommended. Disclosure No.

Effectiveness of Repetitive Hyperbaric Oxygen Therapy for Chronic Limb-Threatening Ischemia.

Lower extremity artery disease is strongly associated with morbidity and is typically addressed through revascularization interventions. We assessed the clinical outcomes of patients with chronic limb-threatening ischemia (CLTI) without revascularization who did and did not undergo repetitive hyperbaric oxygen therapy (HBOT). Between April 2002 and March 2017, the records of 58 patients with CLTI (Rutherford classification 4 in 19% and 5 in 81%) were evaluated retrospectively. HBOT was performed at 2.8 atm of oxygen (HBOT group). The control group included those who could not continue HBOT and historical controls. Patients in poor general health or with an indication for revascularization therapy were excluded. We examined major adverse events (MAEs) and limb salvage rates. Independent predictors and risk stratification were analyzed using a multivariate regression analysis. The mean age was 71±13 years. Of all patients, 67% had diabetes and 43% were undergoing hemodialysis. The mean follow-up period was 4.3±0.8 years. The overall survival rate was 84.5% and 81.0% at 1 and 3 years, respectively. The Cox regression analysis indicated that high body mass index (odds ratio [OR]: 0.86; 95% confidence interval [CI]: 0.76-0.97; p=0.01), well-nourished (OR: 1.21; 95% CI: 1.01-1.45), and HBOT (OR: 0.05; 95% CI: 0.01-0.26; p<0.001) independently predicted absence of MAEs. For major limb amputation, the ankle-brachial index (OR: 0.2; 95% CI: 0.05-0.86; p=0.03) and HBOT (OR: 0.04; 95% CI: 0.004-0.32; p=0.003) were independent predictors. Repetitive, stand-alone HBOT was associated with MAE-free survival and limb salvage in patients with CLTI.

Enriched oxygen improves age-related cognitive impairment through enhancing autophagy.

Age-related cognitive impairment represents a significant health concern, with the understanding of its underlying mechanisms and potential interventions being of paramount importance. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) on cognitive function and neuronal integrity in aged (22-month-old) C57BL/6 mice. Male mice were exposed to HBOT for 2 weeks, and spatial learning and memory abilities were assessed using the Morris water maze. We employed transcriptome sequencing and Gene Ontology (GO) term enrichment analysis to examine the effects of HBOT on gene expression profiles, with particular attention given to synapse-related genes. Our data indicated a significant upregulation of postsynapse organization, synapse organization, and axonogenesis GO terms, likely contributing to improved cognitive performance. Moreover, the hyperphosphorylation of tau, a hallmark of many neurodegenerative diseases, was significantly reduced in the HBO-treated group, both in vivo and in vitro. Transmission electron microscopy revealed significant ultrastructural alterations in the hippocampus of the HBOT group, including an increase in the number of synapses and the size of the active zone, a reduction in demyelinated lesions, and a decreased number of "PANTHOS." Furthermore, Western blot analyses confirmed the upregulation of PSD95, BDNF, and Syn proteins, suggesting enhanced synaptic plasticity and neurotrophic support. Moreover, HBOT increased autophagy, as evidenced by the elevated levels of Beclin-1 and LC3 proteins and the reduced level of p62 protein. Finally, we demonstrated that HBOT activated the AMPK-mTOR signaling pathway, a critical regulator of autophagy. Notably, our findings provide novel insights into the mechanisms by which HBOT ameliorates age-related cognitive impairment, suggesting the potential therapeutic value of this approach.

The therapeutic effect of hyperbaric oxygen therapy in patients with severe to profound idiopathic sudden sensorineural hearing loss

The optimal treatment for sudden sensorineural hearing loss (SSNHL) is unclear. Hyperbaric oxygen therapy (HBOT) has been suggested as a viable option for treatment of SSNHL as it improves vascular dysfunction. In this study, we evaluated the therapeutic effects of HBOT by retrospectively reviewing the records of 2206 patients with SSNHL. 54 who had received HBOT were selected for the HBOT groups, while 59 age-matched controls who had not were selected for the control groups. The HBOT and control groups were divided into subgroups according to intratympanic steroid (ITS) use. Groups A–D had received oral steroids + HBOT, oral steroids only, oral steroids + ITS + HBOT, and oral steroids + ITS, respectively. Of the 113 SSNHL patients, 21 had diabetes mellitus (DM) (2, 0, 9, and 10 patients in Groups A–D, respectively). There was no notable difference in hearing improvement between patients receiving HBOT and those in the control group. However, among diabetic patients, those who underwent HBOT demonstrated a significant improvement in hearing when compared to the control group. The combination of HBOT and steroids could potentially be beneficial for treating severe to profound SSNHL patients with DM.

The use of hyperbaric oxygen therapy in the treatment of hand crush injuries.

Hyperbaric oxygen therapy (HBOT) has been used as an adjuvant treatment for crush injury because it can improve tissue hypoxia and stimulate wound healing. However, the actual role of HBOT in crush hand injury is still unknown. This study is to assess the efficacy of HBOT for crush hand patients, as well as the impact of HBOT initiation timing. Between 2018 and 2021, 72 patients with crush hand injury were retrospectively reviewed. The patients were divided into the HBOT and control group, and each group had 36 patients. The average session of HBOT was 18.2 (5-32 sessions) per patient, and no patient had a complication related to the treatment. The two groups had similar demographics, but HBOT group had larger injured area (73.6 ± 51.0 vs. 48.2 ± 45.5 cm2 , p = 0.03). To better control the confounding factors, we performed the subgroup analysis with cut-off injured area of 50 cm2 . In the patients with smaller injured area (≦50 cm2 ), the HBOT group had shorter wound healing time (29.9 ± 12.9 vs. 41.0 ± 18.9 days, p = 0.03). The early HBOT group (first session ≤72 h post-operatively) had shorter hospital stay (8.1 ± 6.4 vs. 15.5 ± 11.4 days, p = 0.04), faster wound healing (28.7 ± 17.8 vs. 41.1 ± 18.1 days, p = 0.08) and less operations (1.54 ± 0.78 vs. 2.41 ± 1.62, p = 0.06) although the latter two didn't achieve statistical significance. HBOT is safe and effective in improving wound healing of hand crush injury. Early intervention of HBOT may be more beneficial. Future research is required to provide more evidence.

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.

The Effectiveness of Salvage Hyperbaric Oxygen Therapy Following Combined Steroid Therapy for Refractory Sudden Sensorineural Hearing Loss.

Hyperbaric oxygen therapy (HBOT) is an accepted treatment option for sudden sensorineural hearing loss (SSNHL), but it is still recommended in combination with corticosteroids. We investigated the efficacy of salvage HBOT in refractory SSNHL that does not respond to corticosteroid combination therapy. Eighty-four patients were included, who had unilateral SSNHL with an improvement of pure-tone average (PTA) less than 10 dB after using intratympanic plus systemic corticosteroids (combined therapy) as the initial therapy. The control group (n = 66) received no further treatment, and the HBOT group (n = 18) received additional treatment with HBOT (10 sessions in total with 2.5 atmospheres absolute for 1 hour). No differences in PTA or WDS were found between the 2 groups. However, the mean hearing gain in the HBOT group (16.8 ± 4.49 dB) was significantly higher than that in the control group (4.45 ± 1.03 dB) (P = .015). The proportion of patients with hearing recovery (hearing gain of 10 dB or more) after treatment was significantly higher in HBOT group (38.9%) than in the control group (10.6%). In patients with refractory SSNHL after steroid combined therapy, salvage HBOT showed a significant effect on hearing gain and recovery rate.

Effect of hyperbaric oxygen therapy combined with repetitive transcranial magnetic stimulation on vascular cognitive impairment: a randomised controlled trial protocol

IntroductionVascular cognitive impairment (VCI) has an increasing prevalence worldwide, accounting for at least 20%–40% of all diagnoses of dementia. The decline in cognitive function seriously impairs patients’ activities of daily...

Hyperbaric oxygen therapy counteracts Pseudomonas aeruginosa biofilm micro-compartment phenomenon in murine thermal wounds

BackgroundBiofilm antibiotic tolerance is partly explained by the behavior of a biofilm as an independent pharmacokinetic micro-compartment. Hyperbaric oxygen therapy has been shown to potentiate antibiotic effects in biofilms. The present study investigates the effect of hyperbaric oxygen therapy (HBOT) on the biofilm micro-pharmacokinetic/pharmacodynamic behavior of tobramycin in an animal biofilm model. MethodsFull-thickness necroses were created mid-scapular on mice by means of a thermal lesion. After four days, three 16 h seaweed alginate biofilm beads containing Pseudomonas aeruginosa PAO1 were inserted under the necrosis, and three beads were inserted under the adjacent non-affected skin. The mice were randomized to three groups I) HBOT for 1.5 h at 2.8 atm and 0.8 mg tobramycin/mouse subcutaneously; II) Tobramycin as monotherapy, same dose; III) Saline control group. Half the number of mice from group 1 and 2 were sacrificed, and beads were recovered in toto after 3 h and the other half and the placebo mice were sacrificed and beads collected after 4.5 h. ResultsLower CFUs were seen in the burned group receiving HBOT at 3 and 4.5 h compared to beads in the atmospheric environment (p = 0.043 and p = 0.0089). At 3 h, no CFU difference was observed in the non-burned skin (HBOT vs atmospheric). At 4.5 h, CFU in the non-burned skin had lower CFUs in the group receiving HBOT compared to the corresponding atmospheric group (p = 0.02). CFU was higher in the burned skin than in the non-burned skin at 3 h when HBOT was applied (p = 0.04), effect faded out at 4.5 h.At both time points, the tobramycin content in the beads under burned skin were higher in the HBOT group than in the atmospheric groups (p = 0.031 and p = 0.0078). Only at 4.5 h a higher tobramycin content was seen in the beads under the HBOT-treated burned skin than the beads under the corresponding non-burned skin (p = 0.006). ConclusionHBOT, as an anti-biofilm adjuvant treatment of chronic wounds, counteracts biofilm pharmacokinetic micro-compartmentalization through increased available tobramycin and augmented bacterial killing.

Compare the effectiveness of extracorporeal shockwave and hyperbaric oxygen therapy on enhancing wound healing in a streptozotocin-induced diabetic rodent model.

Studies have revealed that both extracorporeal shock-wave therapy (ESWT) and hyperbaric oxygen therapy (HBOT) can accelerate wound healing. This study aimed to compare the effectiveness of ESWT and HBOT in enhancing diabetic wound healing. A dorsal skin defect in a streptozotocin-induced diabetes rodent model was used. Postoperative wound healing was assessed once every 3 days. Histologic examination was performed with hematoxylin and eosin staining. Proliferation marker protein Ki-67 (Ki-67), endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), and 8-hydroxy-2-deoxyguanosine (8-OHdG) were evaluated with immunohistochemical (IHC) staining. The wound area was significantly reduced in the ESWT and HBOT groups compared to that in the diabetic controls. However, the wound healing time was significantly increased in the HBOT group compared to the ESWT group. Histological findings showed a statistical increase in neovascularization and suppression of the inflammatory response by both HBOT and ESWT compared to the controls. IHC staining revealed a significant increase in Ki-67, VEGF, and eNOS but suppressed 8-OHdG expression in the ESWT group compared to the HBOT group. ESWT facilitated diabetic wound healing more effectively than HBOT by suppressing the inflammatory response and enhancing cellular proliferation and neovascularization and tissue regeneration.

Hyperbaric oxygen therapy: a possible choice for patients with resistant thin endometrium during frozen embryo transfer treatments

BackgroundThin endometrium is considered suboptimal for embryo implantation, leading to compromised pregnancy rates without effective therapies. While some studies have reported promoted endometrial growth after a period of hyperbaric oxygen therapy (HBOT) in patients with intrauterine adhesion, there have been no reports in patients with resistant thin endometrium. The purpose of this study was to investigate the impact of HBOT on endometrium growth and pregnancy outcomes in patients with resistant thin endometrium during frozen embryo transfer (FET) treatments.MethodsThis prospective pre-post cohort study was conducted at a university-affiliated assisted reproductive medical center between October 2021 and December 2022. Patients who had experienced at least one canceled transfer cycle due to a thin endometrium(< 7 mm) on the endometrium transformation day, despite the use of standard therapies as well as adjuvant therapies, were enrolled in the study. Patients were assigned voluntarily to either the HBOT group or the concurrent control group. The HBOT group received daily HBOT for at least 10 days during the proliferative phase, in addition to the routine endometrium preparation methods and the concurrent control group underwent cycles without HBOT. Propensity score matching (PSM) was used to ensure comparability between the groups. Both self-control and case-control comparisons were conducted. The primary outcome measured was endometrial thickness (ET) on the day of endometrium transformation. Secondary outcomes included intrauterine pregnancy rate (IPR), embryo implantation rate (IR), miscarriage rate, and others.ResultsPatients in the HBOT group demonstrated a significantly thicker endometrial thickness on the day of endometrium transformation after undergoing therapy (5.76 ± 1.66 vs. 6.57 ± 1.23, P = 0.002). This improvement was accompanied by a decreased rate of cycle cancellations. Baseline parameters and endometrial thickness were comparable between the HBOT group and the concurrent control group during the cycle. The IPR was similar in patients who received cleavage-stage embryos (0.0% vs. 6.7%, P = 1.00), but significantly higher in patients in the HBOT group who received blastocysts (53.8% vs. 18.2%, P = 0.017).ConclusionsA period of HBOT prior to endometrium transformation contributes to increased endometrial thickness and facilitates blastocyst implantation in patients with resistant thin endometrium during FET treatments.Trial registrationThe trial was registered on the Chinese Clinical Trial Registry (registration no. ChiCTR2300072831, retrospectively registered).

Idiopathic sudden sensorineural hearing loss: effectiveness of salvage treatment with intratympanic dexamethasone or hyperbaric oxygen therapy in addition to systemic steroids.

The development of standardized treatments for idiopathic sudden sensorineural hearing loss (ISSNHL) is hampered by uncertainty over the etiology of this disorder. Systemic steroids are historically the primary therapy, with variable hearing outcomes. Over the last two decades, intratympanic steroids (ITS) and hyperbaric oxygen therapy (HBOT) have been proposed as salvage treatments in case of failure of systemic steroids. The present study aims to evaluate the effectiveness of these salvage treatments in addition to systemic steroids. We performed a retrospective study on 75 consecutive patients with a diagnosis of ISSNHL who were admitted to the Department of Otorhinolaryngology of our hospital between December 2018 and December 2022. All patients received primary treatment with systemic steroids. In case of slight or no hearing recovery within the 5th day from the beginning of the therapy (T1), a salvage treatment with ITS or HBOT was proposed. Patients were divided into three groups according to the therapy received: systemic steroids (group A), systemic steroids + HBOT (group B), and systemic steroids + ITS (group C). Pure-tone average at 500, 1000, 2000, and 3000 Hz and the mean gain were evaluated at T1 and 3 months after the beginning of the salvage treatment (T2). The hearing recovery was assessed according to the Siegel's criteria. Sixty-two patients (31 men and 31 women, mean age 56 years) with failure of the primary treatment were definitively enrolled in the study: 34 (54.8%) in group A, 16 (25.8%) in group B, and 12 (19.4%) in group C. The ratio of patients responding to therapy was higher in group A (29.4%) than in groups B (18.75%) and C (16.7%). We did not find any statistically significant difference between groups in terms of mean hearing gain at T2 (17.4 ± 15.4 dB in group A vs. 18.6 ± 21.1 dB in group B and 15.7 ± 14.2 dB in group C, p = 0.9). In our experience, ITS or HBOT associated with systemic steroids, as salvage treatment, did not show significant improvement in hearing outcomes. The evolution of ISSNHL, regardless of the treatment, remains unpredictable.

HBO treatment enhances motor function and modulates pain development after sciatic nerve injury via protection the mitochondrial function

BackgroundPeripheral nerve injury can cause neuroinflammation and neuromodulation that lead to mitochondrial dysfunction and neuronal apoptosis in the dorsal root ganglion (DRG) and spinal cord, contributing to neuropathic pain and motor dysfunction. Hyperbaric oxygen therapy (HBOT) has been suggested as a potential therapeutic tool for neuropathic pain and nerve injury. However, the specific cellular and molecular mechanism by which HBOT modulates the development of neuropathic pain and motor dysfunction through mitochondrial protection is still unclear.MethodsMechanical and thermal allodynia and motor function were measured in rats following sciatic nerve crush (SNC). The HBO treatment (2.5 ATA) was performed 4 h after SNC and twice daily (12 h intervals) for seven consecutive days. To assess mitochondrial function in the spinal cord (L2–L6), high-resolution respirometry was measured on day 7 using the OROBOROS-O2k. In addition, RT-PCR and Immunohistochemistry were performed at the end of the experiment to assess neuroinflammation, neuromodulation, and apoptosis in the DRG (L3–L6) and spinal cord (L2–L6).ResultsHBOT during the early phase of the SNC alleviates mechanical and thermal hypersensitivity and motor dysfunction. Moreover, HBOT modulates neuroinflammation, neuromodulation, mitochondrial stress, and apoptosis in the DRG and spinal cord. Thus, we found a significant reduction in the presence of macrophages/microglia and MMP-9 expression, as well as the transcription of pro-inflammatory cytokines (TNFa, IL-6, IL-1b) in the DRG and (IL6) in the spinal cord of the SNC group that was treated with HBOT compared to the untreated group. Notable, the overexpression of the TRPV1 channel, which has a high Ca2+ permeability, was reduced along with the apoptosis marker (cleaved-Caspase3) and mitochondrial stress marker (TSPO) in the DRG and spinal cord of the HBOT group. Additionally, HBOT prevents the reduction in mitochondrial respiration, including non-phosphorylation state, ATP-linked respiration, and maximal mitochondrial respiration in the spinal cord after SNC.ConclusionMitochondrial dysfunction in peripheral neuropathic pain was found to be mediated by neuroinflammation and neuromodulation. Strikingly, our findings indicate that HBOT during the critical period of the nerve injury modulates the transition from acute to chronic pain via reducing neuroinflammation and protecting mitochondrial function, consequently preventing neuronal apoptosis in the DRG and spinal cord.

Abstract P2073: Hyperbaric Oxygen Therapy Protects The Myocardium From Reductive Stress-induced Proteotoxic Remodeling

Background: Oxygen is the prime source of reactive oxygen species (ROS) in cells. We hypothesize that hyperbaric oxygen therapy (HBOT) can be used as an effective intervention to maintain redox homeostasis in the myocardium. Here, we assessed whether HBOT could prevent RS through enhanced ROS signaling, thereby protecting the hearts from proteotoxic stress. Methods: Cardiac-specific human Nrf2 transgenic (hNrf2-TG) and their non-transgenic littermates (NTG) were used in this study. Mice at the age of 8 weeks were exposed to hyperbaric oxygen (2.5 Bars, 2 hr/day) for 8 weeks. The TG and NTG (n=6) mice without HBOT served as controls. Pre- and post- echocardiography (Vevo 2100) analysis were carried out to assess the structural and functional changes over time in response to HBOT exposure. The influence of HBOT on matrixins (MMP2/9), redox (GSH &amp; NQO1), and cardiac hypertrophy markers (ANF, BNF) were examined using zymography, immunoblotting, and qPCR analysis. The aggregation of proteins in myocardial tissues was detected by Proteostat staining. Results: While the expression of hNrf2 induces RS in the mouse heart, we noticed that HBOT ameliorates the RS through enhanced ROS signaling. A decrease in systemic GSH levels along with the downregulation of ANF and BNF mRNA levels observed in the HBOT group indicates the restoration of the redox homeostasis as well as reduced remodeling of the myocardium. Interestingly, hNRF2-induced RS was suppressed by HBOT as supported by changes in the protein levels for NQO1, GCLC, and GCLM. The degree of protein aggregation in RS hearts was significantly reduced by HBOT. Vevo strain analysis reveals that 8 weeks of HBOT restored the diastolic stretch seen in the RS hearts to a normal diastole-systole velocity equal to NTG mice. A significant decrease in the ejection fraction (80% vs. 55% in TG vs. TG-HBOT), was evident in the TG mice that received HBOT. Repression of matrixins, observed in the hearts of HBOT-TG mice signifies the benefits of HBOT in RS hearts. Conclusion: HBOT directly improves myocardial structure at the tisuue level; maintain the redox status at systemic level, and improves the myocardial performance at functional level. Our study established that HBOT can rescue the myocardium from RS-induced proteotoxic insults.