Hyperbaric oxygen: its mechanisms and efficacy

Resistant Chronic Venous Leg Ulcers: Effect of Adjuvant Systemic Hyperbaric Oxygen Therapy Versus Venous Intervention Alone

The aim of this study was to assess the adjuvant efficacy of adding systemic hyperbaric oxygen therapy (HBOT) to definitive venous intervention for healing of resistant chronic venous leg ulcers (VLUs). From 97 chronic VLUs, 63 were subjected to a pre-study standard wound care. Thirty three ulcers failed to achieve 50% size reduction, after the 4-weeks standard care, and were allocated to be treated with: HBOT plus venous intervention (n = 17), or venous intervention alone (n = 16). Primary outcomes were the change in ulcer area, complete healing frequency and time, as well as ulcer recurrence. There was a history of recurrent ulcer (82.3% vs. 69%) in HBOT versus venous intervention groups, respectively. The comparison between both groups with regard to area change showed non-significant difference after 3 months of therapy, while there was a significant difference at 6 and 12 months. A significant positive correlation was found between the HBO sessions numbers (20-40) and the rate of ulcer size reduction. Ulcer complete closure after 3 months was observed in (41.7%) of HBOT group, versus (23%) in venous intervention group; (p = 0.33). After 12 months, complete closure was observed in (83.3%) of HBOT group, versus (53.8%) in venous intervention group; (p = 0.02). The mean time of complete closure was significantly shorter in HBOT group, (p = 0.001). HBOT may be effective as adjuvant to venous intervention in treatment of chronic resistant VLUs, it should be reserved for persistent ulcer. Randomized controlled trials with larger numbers is still needed to elucidate its exact role and specific indications.

Hyperbaric oxygen therapy for wounds of the face, head and neck

PURPOSE OF REVIEW

Wounds within the face, head, and neck region can have devastating aesthetic, functional, and potentially fatal outcomes for patients and often require multimodality treatment. Here we discuss the role of hyperbaric oxygen for a variety of wounds within the head and neck region and the clinically associated outcomes.

RECENT FINDINGS

Hyperbaric oxygen (HBO) treatment can be useful in the management of wounds and infections within the head and neck region. While there are few randomized controlled clinical trials evaluating the effectiveness of HBO therapy, there is a large amount of retrospective literature supporting its adjunctive role in the treatment of radiation associated head and neck wounds, compromised grafts and flaps, and necrotizing soft tissue infections. The most common treatment protocols are typically initiated at 2-2.4 atmosphere absolute (ATA) at 100% oxygen for 90 min for 30 daily sessions, though this varies significantly in the available literature. In the setting of osteoradionecrosis (ORN) and medication-induced osteonecrosis of the jaw (MRONJ), however, emerging treatments such as the Potentiation by Clodronate (PENTOCLO) protocol may provide more effective treatment that HBO therapy.

SUMMARY

Hyperbaric oxygen therapy should be considered as an adjuvant therapy for head and neck wounds involving radiated soft tissue, compromised local and free flaps, filler-induced soft tissue necrosis or blindness, and for necrotizing soft tissue infection; however, more randomized controlled trials are needed to better evaluate both their clinical impact as well as better establish treatment protocols, particularly in the setting of ORN and MRONJ.

Skull base osteoradionecrosis: from pathogenesis to treatment

PURPOSE OF REVIEW

This review aims to provide a comprehensive analysis of skull base osteoradionecrosis (ORN), a severe and rare complication of radiotherapy for head and neck malignancies. It explores pathogenesis, clinical presentation, diagnostic strategies, and management approaches, emphasizing the importance of multidisciplinary care in addressing this challenging condition.

RECENT FINDINGS

Skull base ORN results from radiotherapy-induced tissue damage, characterized by hypovascularity, hypoxia, and necrosis, often compounded by secondary infections. Advances in radiotherapy techniques, such as intensity-modulated radiotherapy and heavy particles, have reduced ORN incidence, though cases persist, particularly in high-dose radiotherapy fields. Emerging treatments, including hyperbaric oxygen therapy and the pentoxifylline-tocopherol protocol, show promise but lack robust evidence for standardized use. Surgical interventions, especially those incorporating vascularized tissue reconstruction, have demonstrated favorable outcomes in refractory cases. Recent studies underscore the utility of multimodal imaging techniques, including MRI and PET/CT, for distinguishing ORN from tumor recurrence.

SUMMARY

Skull base ORN represents a complex and potentially life-threatening condition requiring tailored, multidisciplinary management. Although advancements in diagnostics and therapeutics have improved outcomes, significant challenges remain, particularly in developing standardized protocols. Further research is needed to refine treatment strategies and improve evidence-based practices for this entity.

Oxy-inflammation in hyperbaric oxygen therapy applications

Hyperbaric Oxygen Therapy (HBOT) is a non-invasive method of O2 delivery that induces systemic hyperoxia. Hyperbaric chamber consists of a pressure vessel and a compressed breathing gas supply, which can regulate internal pressure. The chamber delivers 100% O2 to patients according to predetermined protocols and is monitored by trained personnel. HBOT relies on increasing the inspired O2 fraction (fiO2) and elevating the partial pressure of O2 (pO2). O2 is typically administered at pressures between 1.5 and 3.0 ATA for 60 to 120 minutes, depending on the clinical presentation. Currently, there are 15 indications for HBOT approved by the Undersea and Hyperbaric Medicine Society, categorized into three groups: emergency medicine, wound healing acceleration, and antimicrobial effects. The present narrative review aims to elucidate the mechanisms action underlying HBOT, particularly oxy-inflammation, in various pathologies within these categories.

The Impact of Recreational Diving to a Depth of 40 m on Selected Intracellular DAMPs

Increasingly popular, recreational diving is a physical activity that takes place under extreme environmental conditions, which include hyperoxia, hyperbaria and exposure to cold water. The effects of these factors on the human body induce increased levels of reactive oxygen and nitrogen species in divers' bodies, which may modulate damage-associated molecular pattern (DAMPs), their receptors and the antioxidant response. This study involved 21 divers who descended to a depth of 40 metres. Determinations of selected intracellular DAMPs (high-mobility group box protein 1,HMGB1, S100 calcium-binding proteins A9 and A8, S100A8 and S100A9, heat shock protein family A member 1A, HSPA1A (Hsp70), heat shock protein family B, (small) member 1, HSPB1(Hsp27), thioredoxin, TXN), their receptors (Toll-like receptor 4, TLR4 and receptors for advanced glycation end products, RAGE), nuclear factor-κB (NF-κB) and antioxidant defence markers were performed before, after and 1 h after the dive. A significant transient reduction in HMGB1 expression was observed immediately after the dive at both the mRNA and protein levels. We noted an increase in S100A9 expression, which occurred 1 h post-dive compared to the post-dive time point, and a post-dive decrease in TLR4 expression only at the mRNA level. Diving also influenced the expression of genes encoding key enzymes associated with glutathione synthesis, (glutamate-cysteine ligase, catalytic subunit, GCLC and glutathione synthetase, GSS), and reduced plasma glutathione levels. However, no significant changes were observed in the expression of NF-κB, nitric oxide synthase 2 (NOS2) or circulating DAMP receptors (TLR4 and RAGE). The findings suggest an adaptive response to diving-induced oxidative stress, which appears to be a protective mechanism against an excessive inflammatory response. To our knowledge, this is the first study to analyse the role of intracellular DAMPs in recreational divers.

Advancement of Nanomaterials- and Biomaterials-Based Technologies for Wound Healing and Tissue Regenerative Applications

Patients and healthcare systems face significant social and financial challenges due to the increasing number of individuals with chronic external and internal wounds that fail to heal. The complexity of the healing process remains a serious health concern, despite the effectiveness of conventional wound dressings in promoting healing. Recent advancements in materials science and fabrication techniques have led to the development of innovative dressings that enhance wound healing. To further expedite the healing process, novel approaches such as nanoparticles, 3D-printed wound dressings, and biomolecule-infused dressings have emerged, along with cell-based methods. Additionally, gene therapy technologies are being harnessed to generate stem cell derivatives that are more functional, selective, and responsive than their natural counterparts. This review highlights the significant potential of biomaterials, nanoparticles, 3D bioprinting, and gene- and cell-based therapies in wound healing. However, it also underscores the necessity for further research to address the existing challenges and integrate these strategies into standard clinical practice.

Hyperbaric oxygen therapy attenuated limb ischemia in mice with high-fat diet by restoring Sirtuin 1 and mitochondrial function

Hyperbaric oxygen therapy (HBO) shows promise as a treatment for peripheral artery disease (PAD), particularly when complicated by metabolic syndrome and diabetes. However, its precise effects on endothelial function remain unclear. This study explored the impact of HBO on angiogenesis and apoptosis in high-fat diet (HFD)-fed mice with limb ischemia, focusing on the role of sirtuin 1 (SIRT1). After 8 weeks on a chow or HFD, mice underwent unilateral femoral artery ligation and received HBO (3 ATA, 1 h/day for 5 days). HBO improved blood flow, enhanced vascular density, and reduced apoptosis in ischemic calf muscles of HFD-fed mice. In vitro, human umbilical vein endothelial cells (HUVECs) were subjected to high-glucose and oxygen-glucose deprivation (OGD) conditions, with or without HBO. HBO restored cell proliferation, migration, and tube formation under these conditions, reduced mitochondrial dysfunction, and decreased reactive oxygen species (ROS) production. However, these benefits were reversed by treatment with sirtinol, a SIRT1 inhibitor. HBO also increased SIRT1 expression and shifted mitochondrial dynamics toward fusion. Additionally, HBO upregulated angiogenesis-related proteins (VEGF, VEGFR, and SIRT1) while downregulating apoptosis-associated proteins (Bax, caspase-3, and p53). Collectively, these findings suggest that HBO enhances angiogenesis and reduces apoptosis in both in vivo and in vitro ischemia models, primarily through SIRT1 activation.

Hyperbaric Oxygen Therapy: An Evidence-Based Primer for Emergency Physicians

BACKGROUND

Hyperbaric medicine is a subspecialty that many emergency physicians may not encounter frequently in their daily practice. As such, we hope to provide a review, where we present an overview of hyperbaric oxygen therapy, complications from the therapy, and a description of how the treatments are administered. We also discuss seven emergency indications that may benefit from transfer to a hyperbaric facility for treatment.

OBJECTIVE OF THE REVIEW

Our aim is to provide an overview of hyperbaric oxygen therapy as it pertains to an emergency physician. We hope that this review will help emergency physicians identify conditions that may benefit from transfer to a hyperbaric facility.

DISCUSSION

We discuss seven emergency conditions that may benefit from transfer to a hyperbaric facility for management-decompression sickness, arterial gas embolism, central retinal artery occlusion, carbon monoxide poisoning, crush injury, necrotizing soft tissue infection, and symptomatic anemia. We also describe special considerations for how to transfer patients needing evaluation by a hyperbaric physician.

CONCLUSIONS

This review aims to describe hyperbaric oxygen therapy, identify conditions that may benefit from treatment with hyperbaric oxygen, and discuss management of patients with those conditions as it pertains to an emergency physician.

The role of hyperbaric oxygen therapy in the treatment of diabetic foot ulcers - A literature review

Diabetic Foot Ulcers (DFUs) are chronic foot wounds, in a person with diabetes, which are associated with peripheral arterial insufficiency and/or peripheral neuropathy of the lower limb. Recent UK audit figures report that approximately 50-60 % of DFUs remain unhealed after 12 weeks. Previous research has suggested that ischaemia plays a key role in the pathophysiology of many chronic wounds, including DFUs. For this reason, hyperbaric oxygen therapy (HOT) has been investigated. The study aimed to investigate 1) Current understanding of the physiology of normal wound healing and the pathological mechanisms that occur in DFUs to interrupt these processes; 2) Effectiveness of current DFU treatment approaches; 3) Effectiveness from clinical trials and meta-analyses for any demonstrated therapeutic benefits of HOT in the treatment of DFUs, 4) Patient selection criteria for HOT, and patients who stand to benefit most from treatment. The review found that wound healing is a complex process, involving many cells and signalling molecules, and it remains incompletely understood. However, current evidence suggests that hyperglycaemia, hypoxia, chronic inflammation (due to infection, immune-cell dysfunction or other causes), peripheral neuropathy, and macro- and micro-vascular dysfunction may all adversely affect DFU healing. The review found that current NICE guidelines do not approve HOT therapy in the UK for DFU's, despite encouraging clinical research findings. HOT shows theoretical promise and has been successfully used in the treatment of individual DFUs for several decades. Despite this, there remains a lack of strong clinical evidence of benefits to encourage HOT's wider use. The review found that there were four important patient selection criteria for HOT treatment, including glycaemic control, possible contraindications and complications associated with treatment, ulcer severity and resistance to first and second line treatments. The review concluded that further high-quality clinical research is needed to improve the evidence base.

Exosomes derived from human placental mesenchymal stem cells in combination with hyperbaric oxygen therapy enhance neuroregeneration in a rat model of sciatic nerve crush injury

Peripheral nerve damage continues to be a significant challenge in the field of medicine, with no currently available effective treatment. Currently, we investigated the beneficial effects of human placenta mesenchymal stem cells (PMSCs)- derived exosomes along with hyperbaric oxygen therapy (HBOT) in a sciatic nerve injury model. Seventy-five male mature Sprague-Dawley rats were allocated into five equal groups. In addition to the control group that received no intervention, damaged animals were allocated into four groups as follows: crush group, exosome group, HBOT group, and Exo+HBOT group. After the last neurological evaluations, tissue samples (sciatic nerve and dorsal root ganglion (DRG)) at the injury side, as well as spinal cord segments related to the sciatic nerve were collected to investigate histological, immunohistochemical, biochemical, and molecular characteristics. We found that the volume of the sciatic nerve, the thickness of the myelin sheath, the densities of nerve fibers and Schwann cells, the numerical densities of sensory neurons and glial cells in the DRG, as well as the numerical density of motor neurons in the anterior horn of the spinal cord, the levels of antioxidative factors (GSH, SOD, and CAT) in the sciatic nerve, as well as the neurological functions (EMG latency and SFI) in the treatment groups, especially the Exo+HBOT group, were significantly improved compared to the crush group. This is while the numerical density of glial cells in the spinal cord, the levels of an oxidative factor (MDA), and pro-inflammatory cytokines (IL-1β, TNF-α, and IFN- γ) considerably decreased in the treatment groups, particularly the Exo+HBOT group, compared to the crush group. We conclude that co-administration of PMSCs-derived exosomes and HBOT has synergistic neuroprotective effects in animals undergoing sciatic nerve injury.

Hyperbaric Oxygen Therapy for Managing Cancer Treatment Complications: A Safety Evaluation

Background and Objectives: Hyperbaric oxygen therapy (HBOT) has shown promise in managing complications due to cancer treatments, particularly those related to radiotherapy and surgery. Despite its clinical benefits, concerns persist regarding its potential to influence cancer progression. This study aimed to evaluate the safety and clinical outcomes of HBOT in patients with active or previously treated solid tumors. Methods: A retrospective analysis was conducted on patients with solid tumors who underwent at least five HBOT sessions. Comprehensive data, including patient demographics, cancer type, total number of HBOT sessions, imaging findings, and clinical outcomes (recurrence, metastasis, and mortality), were collected. Descriptive statistics and the relationship between the number of HBOT sessions and long-term cancer outcomes were analyzed. Results: This study included 45 patients (median age: 64 years; 60% male) who received a median of 27 HBOT sessions. At initiation, 27.9% of the patients were classified as cured, 53.5% were in remission, and 18.6% had active cancer. Over a median follow-up period of 783 days, 8.7% experienced recurrence, 2.7% had persistent active cancer, and 59.5% had no recurrence. No HBOT-related complications were observed during the course of HBOT. Statistical analyses revealed no significant correlations between the number of HBOT sessions and metastasis (p = 0.213) or mortality (p = 0.881). Conclusions: HBOT appears to be a safe and effective adjunctive therapy for managing complications in patients with solid tumors. No evidence was found to suggest HBOT contributes to tumor progression, recurrence, or metastasis. Future prospective studies with larger cohorts are needed to confirm these results and further evaluate the therapeutic role of HBOT in oncology.

Air emboli during neuroendovascular procedure treated with hyperbaric oxygen therapy

Air embolism is a rare complication of endovascular procedures with hyperbaric oxygen therapy (HBOT) as a potential treatment. We report a male patient in his 40s presented to the emergency department with the following fluctuating symptoms: headache, aphasia, bilateral arm and hand weakness, numbness and blurry vision. Medical history included remote vertebral artery dissection, hypertension and tobacco use. Initial head CT was normal; CT angiogram revealed bilateral internal carotid artery dissections with significant stenosis. He was taken for emergent carotid intervention. During the intervention, the patient developed agitation, bradycardia and respiratory distress, necessitating intubation. Dyna CT revealed air emboli. HBOT was initiated, leading to complete resolution of air emboli and small haemorrhages after one session. Post-treatment, the patient showed neurological improvement, was extubated and later discharged with mild residual aphasia and dysarthria. This case underscores air emboli as a rare complication in the neurointerventional suite and highlights HBOT as a feasible treatment.

Hyperbaric Oxygen Therapy in the Treatment of Crohn's Disease

Background/Objectives: Our study describes hyperbaric oxygen therapy (HBOT) as an additional therapy in the conservative treatment of Crohn's disease (CD) and its benefit in the early postoperative period to prevent surgical complications and improve gastrointestinal motility. Methods: This retrospective study evaluated HBOT in patients hospitalized at the Clinical Hospital Center Split for complications of CD between 2015 and 2020. Patients (N = 61) aged 19 to 67 with perianal fistulas, abscesses, fistulas, obstruction, stenosis, or bleeding were included, excluding those with ulcerative colitis or requiring intensive care. Patients were retrospectively divided into conservatively and surgically treated groups, and HBOT was administered over 15-25 days, with treatment lasting 60 min at 2.2 absolute atmospheres (ATA). We analyzed treatment outcomes between the HBOT-treated surgical and conservative groups and compared patients treated with HBOT to a cohort from the preceding five years who did not receive HBOT. Results: We treated 61 CD patients with HBOT, including 34 conservatively and 27 surgically treated patients. HBOT significantly reduced disease activity indices (311.7 ± 59.1 vs. 114 ± 29.8; 203.6 ± 24.1 vs. 83.8 ± 15, for conservatively treated patients, and 352.8 ± 45.7 vs. 109 ± 22.8; 270.4 ± 19.7 vs. 140.3 ± 10.6 for surgically treated patients) and accelerated bowel peristalsis recovery, with 94.1% of conservatively treated patients achieving remission. Comparison with a historical cohort showed faster recovery and improved outcomes in the HBOT group. Conclusions: HBOT is useful in postponing or avoiding surgical treatment, and in operated patients, it improves postoperative recovery and reduces the rate of postoperative complications.

Management of laryngeal chondroradionecrosis: A single-center experience

BACKGROUND

Laryngeal chondroradionecrosis (LCRN) is a rare but severe complication of radiation therapy. The study aimed to review the management of LCRN and evaluate the clinical benefit of hyperbaric oxygen therapy (HBOT).

METHODS

We retrospectively analyzed all radiation-induced LCRN patients between 2006 and 2019 at a tertiary medical center. Diagnosis was based on signs and symptoms of Chandler's classification, imaging, and/or histopathology report. The primary outcome was improvement in Chandler's grade after HBOT.

RESULTS

Of 678 irradiated laryngeal cancer patients, 29 (4.3%) were diagnosed with LCRN. The most common primary management was tracheostomy with intravenous steroids and antibiotics (59%). Ten patients received HBOT (34.5%), and six underwent total laryngectomy (21%). In HBOT-treated patients, Chandler's grade significantly improved from a median of 4 (range 2-4) to 2.5 (range 1-4; p = 0.005).

CONCLUSIONS

HBOT may benefit in the management of patients with persistence and unresponsive symptoms of LCRN following radiation therapy for laryngeal SCC.

Five consecutive cases of sensorineural hearing loss associated with inner ear barotrauma due to diving, successfully treated with hyperbaric oxygen

Introduction

This report describes the outcomes of sensorineural hearing loss (SNHL) due to cochlear inner ear barotrauma (IEBt) in five divers treated with hyperbaric oxygen (HBOT).

Methods

The case histories of five consecutive divers presenting with SNHL from IEBt due to diving, were reviewed. All divers provided written consent for their data to be included in the study. All had reference pre-injury audiograms. All noted ear problems during or post-dive. Independent audiologists confirmed SNHL in all divers prior to HBOT, then assessed outcomes after HBOT.

Results

Three divers breathed compressed air on low risk dives, and two were breath-hold. None had symptoms or signs other than hearing loss, and none had vestibular symptoms. All could equalise their middle ears. Inner ear decompression sickness was considered unlikely for all cases. All were treated with HBOT 24 hours to 12 days after diving. Two divers received no steroid treatment, one was treated with HBOT after an unsuccessful 10-day course of steroids, and two divers received steroids two days after commencing HBOT. All divers responded positively to HBOT with substantial improvements in hearing across multiple frequencies and PTA4 measurements. Median improvement across all frequencies (for all divers) was 28 dB, and for PTA4 it was 38 dB.

Conclusions

This is the first case series describing use of HBOT for IEBt-induced SNHL. The variable treatment latency and use/timing of steroids affects data quality, but also reflects pragmatic reality, where steroids have minimal evidence of benefit for IEBt. HBOT may benefit diving related SNHL from IEBt with no evidence of perilymph fistula, and provided the divers can clear their ears effectively. A plausible mechanism is via correction of ischaemia within the cochlear apparatus. More study is required including data collection via national or international datasets, due to the rarity of IEBt.

The efficacy of hyperbaric oxygen therapy for skin perfusion following peripheral tissue injury due to usage of inotropes and vasopressors: a case report

Hyperbaric oxygen therapy (HBOT) has garnered significant attention as a therapeutic modality with potential benefits across a variety of medical conditions, ranging from wound healing and ischemic conditions to neurologic disorders and radiation-induced tissue damage. HBOT involves the administration of 100% oxygen at higher-than-atmospheric pressures, which increases the amount of oxygen dissolved in body fluids and tissues. Those elevated oxygen levels are proposed to facilitate tissue repair, reduce inflammation, and promote angiogenesis. This case report presents a compelling instance of the usefulness of HBOT in promoting skin perfusion and healing following peripheral tissue injury caused by administration of inotropic and vasopressor agents to a septic shock patient.

Is Prompt Hyperbaric Oxygen Adjunctive Therapy Able to Reduce Mortality and Amputation in Management of Necrotizing Soft-Tissue Infection?

Background: Necrotizing soft-tissue infection (NSTI) is a rare and serious disease with high morbidity and mortality. Standard therapeutic concepts have included urgent surgical intervention, broad-spectrum antibiotic treatment, and intensive care. Hyperbaric oxygen therapy (HBOT) is used as adjuvant therapy in some centers, but its benefits remain controversial. Methods: A retrospective analysis was conducted in which 98 patients with a clinical diagnosis of NSTI were treated with standard treatments plus HBOT. The clinical outcomes were wound healing, performance status, hospital length, complication rate, recurrence rate, morbidity (amputation rate), and mortality. Primary or secondary outcomes were compared between the time interval of HBOT and the clinical outcomes. Results: The average times from diagnosis of NSTI to initial HBO treatment and from initial surgery to initial HBO treatment were both significantly longer in dead patients than in surviving patients (P = 0.031; P = 0.020). These two time intervals were both significantly longer in amputated patients than in preserved patients (P = 0.031; P = 0.037). Conclusions: Using combined treatment with early surgical debridement combined with HBOT, it is possible to reduce hospital stay, intensive care unit stay, number of debridements, improve complete wound healing rate, and lower amputation and mortality rates among patients with NSTI. The early onset of HBOT soon after diagnosis, especially during critical conditions, is proved to be associated with higher survival and preservation rates.

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

BACKGROUND

Refractory 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.

METHODS

It 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.

RESULTS

There 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).

CONCLUSION

In 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.

Superomedial Pedicle Technique and Management of Circulation Problems in Gigantomastia : Treatment of Gigantomastia

Breast reduction surgeries encompass a wide range of methods that are continuously evolving to discover more reliable and satisfactory techniques. This presentation aims to address the research gap by sharing outcomes and experiences using the superomedial pedicle in gigantomastia, as well as the implemented protocol for managing nipple-areola complex (NAC) ischemia. The Wise pattern and superomedial pedicle reduction mammaplasty method were utilized in treating 19 patients (38 breasts). The average age of the patients was 41.47 years, with a basal mass index (BMI) of 33.27 kg/m2. The mean sternal notch to nipple (SN-N) length for the entire population was found to be 40.97 cm. On both sides, this length was statistically similar at 41.11 cm on the right side and 40.84 cm on the left side. The average weight of resected tissue from all patients was calculated to be 1793.42 g, with slightly higher weight on the right side at 1800 g compared to the left side's weight of 1786.84 g. Postoperative NAC ischemia occurred in three patients, one bilateral case, and two unilateral cases. The study revealed that in both the groups with and without NAC ischemia, the average values were as follows: age, which ranged from 45.33 to 40.75 years; BMI, ranging from 35.01 kg/m2 to 32.95 kg/m2; SN-N distance, which varied from 40 cm to 41.09 cm; and excision material weights, ranging from 1650 g to 1810.29 g. The p-value in the comparisons was found to be greater than 0.05. These results indicate that age, BMI, SN-N distance, and excision material weight did not have an impact on NAC vascularity issues. All NACs were successfully saved through a protocol involving hyperbaric oxygen therapy (HOT) and vacuum-assisted therapy (VAT). The study suggests that utilizing a superomedial flap is a viable option for treating gigantomastia and highlights the effectiveness of their outlined protocol in managing postoperative complications. While acknowledging the need for comparative studies, the study proposes incorporating HOT and VAT into protocols aimed at saving NACs.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Survival Mechanisms and Retention Strategies in Large-Volume Fat Grafting: A Comprehensive Review and Future Perspectives

INTRODUCTION

Large-volume fat grafting is emerging as a promising technique in plastic and reconstructive surgery. However, the unpredictable graft volume retention rate remains a critical challenge. To address this issue, we need a profound understanding of the survival mechanisms following large-volume fat transplantation. This review summarizes known survival mechanisms and strategies to enhance graft retention.

METHODS

This review comprehensively examines the current literature on the survival mechanisms and retention strategies in large-volume fat grafting. A thorough literature search was conducted using PubMed, Medline and Google Scholar databases, focusing on studies published from 2009 to 2023.

CONCLUSION

In the current research on fat survival mechanisms, few have focused on large-volume fat grafting. This review provides an overview of the survival mechanisms specific to large-volume fat grafting and identifies a survival pattern distinct from that of small-volume fat grafting. Additionally, we have summarized existing strategies to improve graft retention across five stages (harvesting, processing, enrichment, grafting and post-graft care), analyzed their advantages and disadvantages and identified some of the most promising strategies.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266.

Emerging Indications for Hyperbaric Oxygen Treatment: Registry Cohort Study

BACKGROUND

Hyperbaric oxygen (HBO2) treatment is used across a range of medical specialties for a variety of applications, particularly where hypoxia and inflammation are important contributors. Because of its hypoxia-relieving and anti-inflammatory effects HBO2 may be useful for new indications not currently approved by the Undersea and Hyperbaric Medical Society. Identifying these new applications for HBO2 is difficult because individual centers may only treat a few cases and not track the outcomes consistently. The web-based International Multicenter Registry for Hyperbaric Oxygen Therapy captures prospective outcome data for patients treated with HBO2 therapy. These data can then be used to identify new potential applications for HBO2, which has relevance for a range of medical specialties.

OBJECTIVE

Although hyperbaric medicine has established indications, new ones continue to emerge. One objective of this registry study was to identify cases where HBO2 has been used for conditions falling outside of current Undersea and Hyperbaric Medical Society-approved indications and present outcome data for them.

METHODS

This descriptive study used data from a web-based, multicenter, international registry of patients treated with HBO2. Participating centers agree to collect data on all patients treated using standard outcome measures, and individual centers send deidentified data to the central registry. HBO2 treatment programs in the United States, the United Kingdom, and Australia participate. Demographic, outcome, complication, and treatment data, including pre- and posttreatment quality of life questionnaires (EQ-5D-5L) were collected for individuals referred for HBO2 treatment.

RESULTS

Out of 9726 patient entries, 378 (3.89%) individuals were treated for 45 emerging indications. Post-COVID-19 condition (PCC; also known as postacute sequelae of COVID-19; 149/378, 39.4%), ulcerative colitis (47/378, 12.4%), and Crohn disease (40/378, 10.6%) accounted for 62.4% (n=236) of the total cases. Calciphylaxis (20/378, 5.3%), frostbite (18/378, 4.8%), and peripheral vascular disease-related wounds (12/378, 3.2%) accounted for a further 13.2% (n=50). Patients with PCC reported significant improvement on the Neurobehavioral Symptom Inventory (NSI score: pretreatment=30.6; posttreatment=14.4; P<.001). Patients with Crohn disease reported significantly improved quality of life (EQ-5D score: pretreatment=53.8; posttreatment=68.8), and 5 (13%) reported closing a fistula. Patients with ulcerative colitis and complete pre- and post-HBO2 data reported improved quality of life and lower scores on a bowel questionnaire examining frequency, blood, pain, and urgency. A subset of patients with calciphylaxis and arterial ulcers also reported improvement.

CONCLUSIONS

HBO2 is being used for a wide range of possible applications across various medical specialties for its hypoxia-relieving and anti-inflammatory effects. Results show statistically significant improvements in patient-reported outcomes for inflammatory bowel disease and PCC. HBO2 is also being used for frostbite, pyoderma gangrenosum, pterygium, hypospadias repair, and facial filler procedures. Other indications show evidence for improvement, and the case series for all indications is growing in the registry.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/18857.

Hyperbaric Oxygen Therapy to Minimize Orthodontic Relapse in Rabbits

OBJECTIVES

 The purpose of the present study was to discover how hyperbaric oxygen therapy (HBOT) could reduce orthodontic relapse by altering the expressions of hypoxia-inducible factor (HIF)-1 messenger ribonucleic acid (mRNA), type I collagen (Col I), and matrix metalloproteinase-1 (MMP-1) in the gingival supracrestal fibers in rabbits.

MATERIALS AND METHODS

 This study involved 44 male rabbits (Oryctolagus cuniculus) randomly divided into the normal group (K0), the orthodontic group without HBOT (K1), and the orthodontic group with HBOT (K2). Following orthodontic separation of the two upper central incisors, a retention phase and relapse assessment were performed. The HBOT was performed for a period of 2, 4, 6, 8, and 10 days after retention. HIF-1α transcription was assessed employing real-time polymerase chain reaction, whereas Col I and MMP-1 proteins were examined using immunohistochemistry. The orthodontic relapse was measured clinically using a digital caliper.

STATISTICAL ANALYSIS

 We used the one-way analysis of variance followed by Tukey's post hoc for multiple comparisons to measure differences between pairs of means; a p-value of 0.05 was considered statistically significant.

RESULTS

 HBOT significantly increased the HIF-1α mRNA expression (p = 0.0140), increased Col I (p = 0.0043) and MMP-1 (p = 0.0068) on the tensioned and pressured side of the gingival supracrestal fibers, respectively, and clinically decreased the relapse (p = 3.75 × 10-40).

CONCLUSION

 HBOT minimizes orthodontic relapse by influencing HIF-1α expression, collagen synthesis (Col I), and degradation (MMP-1). This result suggests that HBOT has the potential to be used as an adjunctive method in the orthodontic retention phase.

The role of routine cardiac investigations before hyperbaric oxygen treatment

Cardiac complications are a rare but potentially serious consequence of hyperbaric oxygen treatment (HBOT), resulting from increased blood pressure and decreased heart rate and cardiac output associated with treatment. These physiologic changes are generally well-tolerated by patients without preexisting cardiac conditions, although those with known or undetected cardiac disease may be more vulnerable to treatment complications. Currently, there are no universally accepted guidelines for pre-HBOT cardiac screening to identify these patients at heightened risk, leading to variability in practice patterns. In the absence of HBOT-specific evidence, screening protocols might be adapted from the diving medicine community; however, given the important differences in physiological stressors, these may not be entirely applicable to patients undergoing HBOT. Traditional cardiac investigations such as electro- and echo-cardiograms are limited in their ability to detect relevant risk modifying states in the pre-HBOT patient, stymieing their cost-effectiveness as routine tests. In the absence of strong evidence to support routine cardiac investigation, we argue that a comprehensive history and physical exam - tailored to identify high-risk patients based on clinical parameters - may serve as a more practical screening tool. While certain unique patient groups such as those undergoing dialysis or with implanted cardiac devices may warrant specialised assessment, thorough evaluation may be sufficient to identify many patients unlikely to benefit from cardiac investigation in the pre-HBOT setting. A clinical decision-making tool based on suggested low-risk and high-risk features is offered to guide the use of targeted cardiac investigation prior to HBOT.

Exploring Photobiomodulation Therapy and Regenerative Medicine for Diabetic Foot Ulcers: Pathogenesis and Multidisciplinary Treatment Approach

Introduction: Diabetes is associated with several debilitating complications, including the development of diabetic foot ulcers (DFUs), which can have serious consequences. This study emphasizes a multidisciplinary approach, providing a thorough overview of DFU pathogenesis and available treatments. Methods: An extensive literature review, covering studies published between 2000 and 2023, was conducted to gather data on DFU pathophysiology and treatments, including wound dressings, photobiomodulation, off-loading devices, adjunct medicines, and stem cell therapy. Results: DFUs are complicated due to infection, ischemia, and neuropathy. Sufficient wound dressings maintain a moist environment, promoting autolytic debridement and facilitating the healing process. Through cellular mechanisms, photobiomodulation therapy (PBM) was observed to expedite the healing process. Additionally, off-loading devices were invented to reduce ulcer pressure and promote healing. Adjunct therapies such as negative pressure wound therapy and hyperbaric oxygen therapy were identified as valuable tools for enhancing healing outcomes. Furthermore, autologous and allogeneic stem cell treatments exhibited the potential for promoting tissue regeneration and expediting the healing process. Conclusion: The complex pathophysiology of DFUs necessitates a multimodal treatment approach. Essential components include PBM, wound dressings, off-loading devices, adjunct treatments, and stem cell therapy.

Hyperbaric Oxygenation: Can It Be a Novel Supportive Method in Acute Kidney Injury? Data Obtained from Experimental Studies

Despite constant achievements in treatment, acute kidney injury (AKI) remains a significant public health problem and a cause of mortality in the human population. In developed countries, AKI is a significant and frequent hospital complication, especially among patients admitted to intensive care units, where mortality rates can reach up to 50%. In addition, AKI has been implicated as an independent risk factor for the development of chronic kidney disease. Hyperbaric oxygenation (HBO) has been used as a primary or adjunctive therapy for the past 50 years, both in experimental and clinical studies. HBO is a treatment in which the patient is occasionally exposed to 100% oxygen at a pressure greater than atmospheric pressure at sea level. However, despite decades of extensive research, the potentially beneficial effects of this therapeutic approach are still not fully understood, although many potential mechanisms have been proposed, such as antioxidative, anti-inflammatory, anti-apoptotic, etc. Furthermore, the low cost and insignificant adverse events make HBO a potentially important strategy in the prevention and treatment of different diseases. Considering all of this, this review highlights the potential role of HBO in maintaining cellular homeostasis disrupted due to AKI, caused in different experimental models.

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.

Comparative analysis of linezolid, vancomycin, and hyperbaric oxygen therapies in a rat model of ventriculoperitoneal shunt infection

PURPOSE

Staphylococcus epidermidis is the most common causative microorganism of ventriculoperitoneal shunt infections. This study aimed to compare linezolid and vancomycin treatments and to examine the effect of these antibiotics alone and combined with hyperbaric oxygen therapy on the amount of bacterial colonies in the experimental S. epidermidis shunt infection model.

METHODS

A shunt catheter was placed in the cisterna magna of 49 adult male Wistar albino rats. The rats were randomly divided into seven groups, as follows: sterile control, infected control, vancomycin, linezolid, hyperbaric oxygen, vancomycin + hyperbaric oxygen, linezolid + hyperbaric oxygen. In all groups except the sterile control group, 0.2 ml 107 CFU/mL S. epidermidis was inoculated to the cisterna magna. Parenteral vancomycin was administered 40 mg/kg/day to the vancomycin groups, and 50 mg/kg/day of enteral linezolid to the linezolid groups. Hyperbaric oxygen groups were given 100% oxygen at a pressure of 2.4 ATA for 50 min a day. One day after the last treatment, colony quantities in the shunt catheters and CSF were analyzed.

RESULTS

The number of CSF colonies in the linezolid group was significantly lower than in the vancomycin group (p < 0.05). The number of CSF colonies in the linezolid + HBO group was significantly lower than in the vancomycin + HBO group (p < 0.05).

CONCLUSIONS

Linezolid treatment was found to be more effective than vancomycin in ventriculoperitoneal shunt infection caused by S. epidermidis. There was no statistical difference among other treatment groups. Hyperbaric oxygen therapy is shown to contribute to the sterilization of cultures.

Hyperbaric oxygen therapy ameliorates intestinal and systematic inflammation by modulating dysbiosis of the gut microbiota in Crohn's disease

BACKGROUND

Dysbiosis of the gut microbiota is pivotal in Crohn's disease (CD) and modulated by host physiological conditions. Hyperbaric oxygen therapy (HBOT) is a promising treatment for CD that can regulate gut microbiota. The relationship between HBOT and the gut microbiota in CD remains unknown.

METHODS

CD patients were divided into an HBOT group (n = 10) and a control group (n = 10) in this open-label prospective interventional study. The fecal samples before and after HBOT were used for 16 S rRNA gene sequencing and fecal microbiota transplantation (FMT). A colitis mouse model was constructed using dextran sulfate sodium, and intestinal and systematic inflammation was evaluated. The safety and long-term effect of HBOT were observed.

RESULTS

HBOT significantly reduced the level of C-reactive protein (CRP) (80.79 ± 42.05 mg/L vs. 33.32 ± 18.31 mg/L, P = 0.004) and the Crohn's Disease Activity Index (CDAI) (274.87 ± 65.54 vs. 221.54 ± 41.89, P = 0.044). HBOT elevated the declined microbial diversity and ameliorated the altered composition of gut microbiota in patients with CD. The relative abundance of Escherichia decreased, and that of Bifidobacterium and Clostridium XIVa increased after HBOT. Mice receiving FMT from donors after HBOT had significantly less intestinal inflammation and serum CRP than the group before HBOT. HBOT was safe and well-tolerated by patients with CD. Combined with ustekinumab, more patients treated with HBOT achieved clinical response (30%vs.70%, P = 0.089) and remission (20%vs.50%, P = 0.160) at week 4.

CONCLUSIONS

HBOT modulates the dysbiosis of gut microbiota in CD and ameliorates intestinal and systematic inflammation. HBOT is a safe option for CD and exhibits a promising auxiliary effect to ustekinumab.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2200061193. Registered 15 June 2022, https://www.chictr.org.cn/showproj.html?proj=171605 .

A Prospective, Blinded, Open-Label Clinical Trial to Assess the Ability of Fluorescent Light Energy to Enhance Wound Healing after Mastectomy in Female Dogs

Mammary gland tumors represent the most frequently diagnosed malignant neoplasm in intact female dogs, and surgical removal represents the current gold standard treatment. To promote wound healing and prevent possible bacterial contamination, perioperative antimicrobials are commonly used in clinical practice, even though there are no publications establishing guidelines for the use of such drugs in canine mastectomy. The aim of the present study was to evaluate the ameliorative effect of fluorescent light energy on the quality of the healing process after mastectomy surgery in female dogs, in the absence of perioperative antimicrobial administration. Nine female dogs received a multiple-gland mastectomy due to gland tumors and received FLE application immediately after surgery and then five days after. The surgical incisions were evaluated by a blind investigator over time using the Modified Hollander Cosmesis and Modified Draize Wound Healing Score systems. Statistical analysis revealed a significant ameliorative effect of FLE in the control of step-off borders, contour irregularities, and excessive distortion. In addition, erythema, edema, and serous discharge were lower for those wounds managed with FLE. These results underscore the advantageous impact of FLE on the healing of post-mastectomy wounds in female dogs, offering the dual benefits of reducing potential infection risks and lessening the home care burden for pet owners.

Hyperbaric Oxygen Reduces Oxidative Stress Impairment and DNA Damage and Simultaneously Increases HIF-1α in Ischemia-Reperfusion Acute Kidney Injury

The central exacerbating factor in the pathophysiology of ischemic-reperfusion acute kidney injury (AKI) is oxidative stress. Lipid peroxidation and DNA damage in ischemia are accompanied by the formation of 3-nitrotyrosine, a biomarker for oxidative damage. DNA double-strand breaks (DSBs) may also be a result of postischemic AKI. γH2AX(S139) histone has been identified as a potentially useful biomarker of DNA DSBs. On the other hand, hypoxia-inducible factor (HIF) is the "master switch" for hypoxic adaptation in cells and tissues. The aim of this research was to evaluate the influence of hyperbaric oxygen (HBO) preconditioning on antioxidant capacity estimated by FRAP (ferric reducing antioxidant power) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assay, as well as on oxidative stress parameter 3-nitrotyrosine, and to assess its effects on γH2AX(S139), HIF-1α, and nuclear factor-κB (NF-κB) expression, in an experimental model of postischemic AKI induced in spontaneously hypertensive rats. The animals were divided randomly into three experimental groups: sham-operated rats (SHAM, n = 6), rats with induced postischemic AKI (AKI, n = 6), and group exposed to HBO preconditioning before AKI induction (AKI + HBO, n = 6). A significant improvement in the estimated glomerular filtration rate, eGFR, in AKI + HBO group (p < 0.05 vs. AKI group) was accompanied with a significant increase in plasma antioxidant capacity estimated by FRAP (p < 0.05 vs. SHAM group) and a reduced immunohistochemical expression of 3-nitrotyrosine and γH2AX(S139). Also, HBO pretreatment significantly increased HIF-1α expression (p < 0.001 vs. AKI group), estimated by Western blot and immunohistochemical analysis in kidney tissue, and decreased immunohistochemical NF-κB renal expression (p < 0.01). Taking all of these results together, we may conclude that HBO preconditioning has beneficial effects on acute kidney injury induced in spontaneously hypertensive rats.

Hyperbaric oxygen therapy for poststroke insomnia: a systematic review and meta-analysis protocol

INTRODUCTION

Insomnia stands as a frequent consequence of a cerebrovascular event, afflicting a substantial fraction of those who endure the aftermath of stroke. The ramifications of insomnia following a stroke can further exacerbate cognitive and behavioural anomalies while hindering the process of neurological convalescence. While several randomised controlled trials (RCTs) have scrutinised the effects of hyperbaric oxygen therapy (HBOT) on poststroke insomnia, the advantages and drawbacks persist in a state of ambiguity. We advocate for a systematic review and meta-analysis of randomised clinical trials to comprehensively evaluate the effectiveness and safety of HBOT in the context of poststroke insomnia.

METHODS AND ANALYSIS

A systematic search will be conducted from nine major databases (PubMed, Web of Science, EMBASE, VIP Information Database, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, China Biomedical Literature Database and Wanfang Database, Physiotherapy Evidence Database (PEDro)) for HBOT for poststroke insomnia of RCTs. The search procedures will adhere to a rigorous approach, commencing from the inception date of each database and continuing until 1 November 2023, with inquiries conducted exclusively in English and Chinese. The primary outcome will focus on the alteration in the quality of sleep while secondary outcomes will encompass the evaluation of adverse events and the rate of reoccurrence. The process of selecting studies, extracting data and evaluating the quality of research will be carried out independently by two reviewers. The quality of the included literature will be assessed using the tools of the Cochrane Collaboration. Meta-analysis will be performed by using RevMan V.5.4 and STATA V.16.0.b software. Finally, the quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluation method.

ETHICS AND DISSEMINATION

As all data are derived from published investigations via databases without direct patient contact, ethical approval is obviated in this study. The scientific studies will be published in professional academic publications.

PROSPERO REGISTRATION NUMBER

CRD42023468442.

Engineering tumor-oxygenated nanomaterials: advancing photodynamic therapy for cancer treatment

Photodynamic therapy (PDT), a promising treatment modality, employs photosensitizers to generate cytotoxic reactive oxygen species (ROS) within localized tumor regions. This technique involves administering a photosensitizer followed by light activation in the presence of oxygen (O2), resulting in cytotoxic ROS production. PDT's spatiotemporal selectivity, minimally invasive nature, and compatibility with other treatment modalities make it a compelling therapeutic approach. However, hypoxic tumor microenvironment (TME) poses a significant challenge to conventional PDT. To overcome this hurdle, various strategies have been devised, including in-situ O2 generation, targeted O2 delivery, tumor vasculature normalization, modulation of mitochondrial respiration, and photocatalytic O2 generation. This review aims to provide a comprehensive overview of recent developments in designing tumor-oxygenated nanomaterials to enhance PDT efficacy. Furthermore, we delineate ongoing challenges and propose strategies to improve PDT's clinical impact in cancer treatment.

Oxygen Therapy to Enhance Wound Healing After Revascularization

Oxygen is one of the important factors for wound healing and infection control. The revascularization procedure is amended to correct the tissue hypoxia problem by increasing the blood flow to obtain an adequate amount of oxygen. Hypoxic wounds are still the issue in the cases of unsuccessful or incomplete revascularization. The issue needs to be clarified and confirmed by proper methods for management to achieve wound healing and prevent limb loss. Oxygen therapy may benefit in the case of remaining hypoxia or wound infection in postrevascularization.

Outcome of Chronic Foot Osteomyelitis Treated With Hyperbaric Oxygen: An Observational Study

Chronic refractory osteomyelitis of the foot stands as a formidable challenge in medical care, associated with significant morbidity and escalating healthcare costs. Traditional therapeutic approaches, including surgical debridement and systemic antibiotics, often fall short, leaving patients and clinicians in search of more efficacious interventions. Hyperbaric oxygen therapy (HBOT), an innovative therapeutic modality, has recently emerged as a promising adjunct therapy, offering a beacon of hope in this therapeutic conundrum. In this groundbreaking observational study, we meticulously analyzed the experiences of 80 patients suffering from chronic refractory osteomyelitis of the foot. Following surgical debridement and tailored antibiotic therapy, each patient was treated with HBOT at 2.5 atmospheres absolute for 120 min, 5 days a week, spanning an average of 50 days. Our primary endpoints focused on complete eradication of infection, recurrence metrics, and any adverse effects linked to HBOT. Astonishingly, 68 of the 80 patients (85%) achieved a total infection clearance, maintaining this status through a mean follow-up period of 36 months, all without a single report of HBOT-induced complications. Our compelling findings advocate that HBOT, synergized with standard surgical and antibiotic regimens, can revolutionize the treatment landscape for chronic refractory osteomyelitis of the foot. Given these promising preliminary results, there's an imperative need for extensive research to delineate the long-term advantages and to fine-tune HBOT protocols, potentially paving the way for a new therapeutic gold standard.

Fournier's gangrene: a review of predictive scoring systems and practical guide for patient management

This article aims to provide a practical guide for patient management and an overview of the predictive scorings for Fournier's gangrene (FG) that are available to aid clinicians. A literature was performed reviewing currently used scoring systems for FG and presenting a practical guide for its management based on the available evidence. There are four specific scoring systems available for the assessment of FG although few other non-specific and generic tools also exist. These specific tools include Laboratory Risk Indicator for Necrotizing Fasciitis, Fournier's Gangrene Severity Index, Uludag Fournier's Gangrene Severity Index, and Simplified Fournier's Gangrene Severity Index and help calculate expected mortality. Our proposed algorithm covers primary assessment, resuscitative interventions, initial investigations, urgent care, post-operative care, and long-term follow-up. The management of the FG patient can be divided into initial resuscitation, surgical debridement, ongoing ward management with antibiotic therapy, wound reconstruction, and long-term follow-up. Each facet of care is vital and requires multidisciplinary team expertise for optimal outcomes. Whilst mortality continues to improve, it remains significant, reflecting the severe and life-threatening nature of FG. More research is certainly needed into how this care is individualised, and to ensure that long-term outcomes in FG include quality of life measures after discharge.

Cryogenic Media in Biomedical Applications: Current Advances, Challenges, and Future Perspectives

This paper explores the crucial role of cryogenic mediums in driving breakthroughs within the biomedical sector. The objective was to investigate, critically discuss, and present the current knowledge and state-of-the-art practices, along with the challenges and perspectives of the most common applications. Through an extensive literature review, this work aims to supplement existing research, offering a comprehensive and up-to-date understanding of the subject. Biomedical research involving cryogenic mediums is advancing on multiple fronts, including the development of advanced medical technologies, clinical treatments for life-threatening conditions, high-quality biospecimen preservation, and antimicrobial interventions in industrial food processing. These advances open new horizons and present cutting-edge opportunities for research and the medical community. While the current body of evidence showcases the impressive impact of cryogenic mediums, such as nitrogen, helium, argon, and oxygen, on revolutionary developments, reaching definitive conclusions on their efficiency and safety remains challenging due to process complexity and research scarcity with a moderate certainty of evidence. Knowledge gaps further underline the need for additional studies to facilitate cryogenic research in developing innovative technological processes in biomedicine. These advancements have the potential to reshape the modern world and significantly enhance the quality of life for people worldwide.

Oral Surgery and Osteoradionecrosis in Patients Undergoing Head and Neck Radiation Therapy: An Update of the Current Literature

Osteoradionecrosis (ORN) is a serious long-term complication of head and neck radiotherapy (RT), which is often triggered by dental extractions. It results from avascular aseptic necrosis due to irradiated bone damage. ORN is challenging to treat and can lead to severe complications. Furthermore, ORN causes pain and distress, significantly reducing the patient's quality of life. There is currently no established preventive strategy. This narrative review aims to provide an update for the clinicians on the risk of ORN associated with oral surgery in head and neck RT patients, with a focus on the timing suitable for the oral surgery and possible ORN preventive treatments. An electronic search of articles was performed by consulting the PubMed database. Intervention and observational studies were included. A multidisciplinary approach to the patient is highly recommended to mitigate the risk of RT complications. A dental visit before commencing RT is highly advised to minimize the need for future dental extractions after irradiation, and thus the risk of ORN. Post-RT preventive strategies, in case of dento-alveolar surgery, have been proposed and include antibiotics, hyperbaric oxygen (HBO), and the combined use of pentoxifylline and tocopherol ("PENTO protocol"), but currently there is a lack of established standards of care. Some limitations in the use of HBO involve the low availability of HBO facilities, its high costs, and specific clinical contraindications; the PENTO protocol, on the other hand, although promising, lacks clinical trials to support its efficacy. Due to the enduring risk of ORN, removable prostheses are preferable to dental implants in these patients, as there is no consensus on the appropriate timing for their safe placement. Overall, established standards of care and high-quality evidence are lacking concerning both preventive strategies for ORN as well as the timing of the dental surgery. There is an urgent need to improve research for more efficacious clinical decision making.

Hyperbaric oxygen treatment in carbon monoxide poisoning - Does it really matter?

Carbon monoxide (CO) is an odorless and colorless gas that can lead to fulminant and life-threatening intoxications. Besides an early diagnosis, an appropriate treatment of the intoxication is important. In this context the reduction of CO concentration in blood and tissues is crucial revealing hyperbaric oxygen treatment (HBO) as a highly promising tool. However, the benefit of HBO in CO intoxications is still considered controversial. In this review, we discuss the evidence of the role of HBO treatment in isolated CO intoxication.

Evaluating the Efficacy of Hyperbaric Oxygen Therapy in Digital Frostbite

Frostbite is a limb threatening, cold-induced tissue injury most commonly affecting the extremities. Hyperbaric oxygen therapy (HBOT) is a proposed adjunctive treatment for this condition, which acts by increasing cellular oxygen availability in damaged tissues. Currently, there is a lack of data regarding the effectiveness of HBOT. Therefore, the purpose of this study is to further the research as one of the largest retrospective comparative cohort studies to date. We evaluated the efficacy of HBOT in the treatment of digital frostbite compared to a non-HBOT-treated group, with a focus on amputation outcomes between each group. A multicenter retrospective cohort study was performed from January 2016 to August 2021 observing patients seen for frostbite. Amputation characteristics and encounter outcomes of patients treated with HBOT were compared to those in patients treated without HBOT. A one-to-one matching of HBOT-treated and non-HBOT-treated patients was also performed, followed by chi-square and Fisher's exact test statistical analysis. The results of the study found a low overall amputation rate of 5.2% across both cohorts. Comparison between groups identified no statistical difference between HBOT and non-HBOT groups regarding amputation characteristics through matched cohort analysis. However, an increased length of hospital stay in patients treated with HBOT (22.2 days) compared to the non-HBOT group (6.39 days) was identified. Based on this study, recommendations for future HBOT studies should evaluate the efficacy of HBOT for more severe cases of frostbite, with additional consideration for cost analysis studies.

Exosomes: Potential key players towards novel therapeutic options in diabetic wounds

Diabetic wounds are usually difficult to heal, and wounds in foot in particular are often aggravated by infection, trauma, diabetic neuropathy, peripheral vascular disease and other factors, resulting in serious foot ulcers. The pathogenesis and clinical manifestations of diabetic wounds are complicated, and there is still a lack of objective and in-depth laboratory diagnosis and classification standards. Exosomes are nanoscale vesicles containing DNA, mRNA, microRNA, cyclic RNA, metabolites, lipids, cytoplasm and cell surface proteins, etc., which are involved in intercellular communication and play a crucial role in vascular regeneration, tissue repair and inflammation regulation in the process of diabetic wound healing. Here, we discussed exosomes of different cellular origins, such as diabetic wound-related fibroblasts (DWAF), adipose stem cells (ASCs), mesenchymal stem cells (MSCs), immune cells, platelets, human amniotic epithelial cells (hAECs), epidermal stem cells (ESCs), and their various molecular components. They exhibit multiple therapeutic effects during diabetic wound healing, including promoting cell proliferation and migration associated with wound healing, regulating macrophage polarization to inhibit inflammatory responses, promoting nerve repair, and promoting vascular renewal and accelerating wound vascularization. In addition, exosomes can be designed to deliver different therapeutic loads and have the ability to deliver them to the desired target. Therefore, exosomes may become an innovative target for precision therapeutics in diabetic wounds. In this review, we summarize the latest research on the role of exosomes in the healing of diabetic wound by regulating the pathogenesis of diabetic wounds, and discuss their potential applications in the precision treatment of diabetic wounds.

Human Placental Mesenchymal Stem Cell-derived Exosomes in Combination with Hyperbaric Oxygen Synergistically Promote Recovery after Spinal Cord Injury in Rats

Spinal cord injury (SCI) is a critical medical condition during which sensorimotor function is lost. Current treatments are still unable to effectively improve these conditions, so it is important to pay attention to other effective approaches. Currently, we investigated the combined effects of human placenta mesenchymal stem cells (hPMSCs)-derived exosomes along with hyperbaric oxygen (HBO) in the recovery of SCI in rats. Ninety male mature Sprague-Dawley (SD) rats were allocated into five equal groups, including; sham group, SCI group, Exo group (underwent SCI and received hPMSCs-derived exosomes), HBO group (underwent SCI and received HBO), and Exo+HBO group (underwent SCI and received hPMSCs-derived exosomes plus HBO). Tissue samples at the lesion site were obtained for the evaluation of stereological, immunohistochemical, biochemical, molecular, and behavioral characteristics. Findings showed a significant increase in stereological parameters, biochemical factors (GSH, SOD, and CAT), IL-10 gene expression and behavioral functions (BBB and EMG Latency) in treatment groups, especially Exo+HBO group, compared to SCI group. In addition, MDA levels, the density of apoptotic cells and gliosis, as well as expression of inflammatory genes (TNF-α and IL-1β) were considerably reduced in treatment groups, especially Exo+HBO group, compared to SCI group. We conclude that co-administration of hPMSCs-derived exosomes and HBO has synergistic neuroprotective effects in animals undergoing SCI.

Hyperbaric oxygen therapy and coenzyme Q10 synergistically attenuates damage progression in spinal cord injury in a rat model

BACKGROUND

Identifying effective spinal cord injury (SCI) treatments remains a major challenge, and current approaches are still unable to effectively improve its. Currently, we investigated the combined effects of hyperbaric oxygen (HBO) along with coenzyme Q10 (CoQ10) in the recovery of SCI in rats.

MATERIAL AND METHODS

Ninety female mature Sprague-Dawley rats were allocated into five equal groups, including; sham group, SCI group, HBO group (underwent SCI and received HBO), CoQ10 group (underwent SCI and received CoQ10), and HBO+CoQ10 group (underwent SCI and received HBO plus CoQ10). Tissue samples at the lesion site were obtained for evaluation of stereological, immunohistochemical, biochemical, molecular. Also, functional tests were performed to evaluate of behavioral properties.

RESULTS

We found that a significant increase in stereological parameters, biochemical factors (GSH, SOD and CAT), IL-10 gene expression and behavioral functions (BBB and EMG Latency) in the treatment groups, especially HBO+CoQ10 group, compared to SCI group. In addition, MDA levels, the density of apoptotic cells, as well as expression of inflammatory genes (TNF-α and IL-1β) were considerably reduced in the treatment groups, especially HBO+CoQ10 group, compared to SCI group.

CONCLUSION

We conclude that co-administration of HBO and HBO+CoQ10 has a synergistic neuroprotective effects in animals undergoing SCI.

Hyperbaric oxygen treatment in children: experience in 329 patients

INTRODUCTION

Paediatric patients, like adults, may undergo hyperbaric oxygen treatment (HBOT) in both life-threatening situations and chronic diseases. There are particular challenges associated with managing paediatric patients for HBOT. This paper documents the indications, results, complications, and difficulties that occur during HBOT for a large cohort of paediatric patients and compares them with adult data in the literature. Methods used to reduce these difficulties and complications in children are also discussed.

METHODS

This was a 15-year retrospective review of paediatric patients treated with HBOT at two hyperbaric centres. Between January 2006 and June 2021, patients under the age of 18 who received at least one session of HBOT were included.

RESULTS

Three hundred and twenty-nine paediatric patients underwent a total of 3,164 HBOT exposures. Two-hundred and fifty-four patients (77.2%) completed treatment as planned and 218 (66.5%) achieved treatment goals without complications. Two patients treated for carbon monoxide poisoning exhibited neurological sequelae. Amputation was performed in one patient with limb ischaemia. Middle ear barotrauma events occurred in five treatments. No central nervous system oxygen toxicity was recorded during the treatments.

CONCLUSIONS

This patient series indicates that HBOT can be safely performed in pediatric patients with low complication rates by taking appropriate precautions. The cooperation of hyperbaric medicine physicians and other physicians related to paediatric healthcare is important in order for more patients to benefit from this treatment. When managing intubated patients an anaesthesiologist may need to participate in the treatment in order to perform necessary interventions.

Identifying the Target Traumatic Brain Injury Population for Hyperbaric Oxygen Therapy

Traumatic brain injury (TBI) results from direct penetrating and indirect non-penetrating forces that alters brain functions, affecting millions of individuals annually. Primary injury following TBI is exacerbated by secondary brain injury; foremost is the deleterious inflammatory response. One therapeutic intervention being increasingly explored for TBI is hyperbaric oxygen therapy (HBOT), which is already approved clinically for treating open wounds. HBOT consists of 100% oxygen administration, usually between 1.5 and 3 atm and has been found to increase brain oxygenation levels after hypoxia in addition to decreasing levels of inflammation, apoptosis, intracranial pressure, and edema, reducing subsequent secondary injury. The following review examines recent preclinical and clinical studies on HBOT in the context of TBI with a focus on contributing mechanisms and clinical potential. Several preclinical studies have identified pathways, such as TLR4/NF-kB, that are affected by HBOT and contribute to its therapeutic effect. Thus far, the mechanisms mediating HBOT treatment have yet to be fully elucidated and are of interest to researchers. Nonetheless, multiple clinical studies presented in this review have examined the safety of HBOT and demonstrated the improved neurological function of TBI patients after HBOT, deeming it a promising avenue for treatment.

Therapeutic management of severe spinal cord decompression sickness in a hyperbaric center

Introduction

Spinal cord decompression sickness (scDCS) unfortunately has a high rate of long-term sequelae. The purpose of this study was to determine the best therapeutic management in a hyperbaric center and, in particular, the influence of hyperbaric treatment performed according to tables at 4 atm (Comex 30) or 2.8 atm abs (USNT5 or T6 equivalent).

Methods

This was a retrospective study that included scDCS with objective sensory or motor deficit affecting the limbs and/or sphincter impairment seen at a single hyperbaric center from 2010 to 2020. Information on dive, time to recompression, and in-hospital management (hyperbaric and medical treatments such as lidocaine) were analyzed as predictor variables, as well as initial clinical severity and clinical deterioration in the first 24 h after initial recompression. The primary endpoint was the presence or absence of sequelae at discharge as assessed by the modified Japanese Orthopaedic Association score.

Results

102 divers (52 ± 16 years, 20 female) were included. In multivariate analysis, high initial clinical severity, deterioration in the first 24 h, and recompression tables at 4 atm versus 2.8 atm abs for both initial and additional recompression were associated with incomplete neurological recovery. Analysis of covariance comparing the effect of initial tables at 2.8 versus 4 atm abs as a function of initial clinical severity showed a significantly lower level of sequelae with tables at 2.8 atm. In studying correlations between exposure times to maximum or cumulative O2 dose and the degree of sequelae, the optimal initial treatment appears to be a balance between administration of a high partial pressure of O2 (2.8 atm) and a limited exposure duration that does not result in pulmonary oxygen toxicity. Further analysis suggests that additional tables in the first 24-48 h at 2.8 atm abs with a Heliox mixture may be beneficial, while the use of lidocaine does not appear to be relevant.

Conclusion

Our study shows that the risk of sequelae is related not only to initial severity but also to clinical deterioration in the first 24 h, suggesting the activation of biological cascades that can be mitigated by well-adapted initial and complementary hyperbaric treatment.

Management of Fournier's gangrene: a practical guide for clinicians

Fournier's gangrene is a localised form of necrotising fasciitis affecting the external genitalia, perineal and perianal regions. Although rare, it is associated with high rates of morbidity and mortality, so clinician awareness is essential for prompt treatment. Risk factors include diabetes mellitus, hypertension, chronic alcoholism and immunosuppression. Perineal pain in patients with sepsis should be treated with a high level of suspicion and early surgical referral is required as prompt debridement can improve outcomes. Repeated surgical intervention and antimicrobial therapy are often needed and recovery can take a long time, with a long-term impact on quality of life. This article discusses the natural history of Fournier's gangrene, aetiology, risk factors, investigations and treatments with an algorithm to support clinical practice.