Gas Inhalation Research Articles

Mild hypercapnia before reperfusion reduces ischemia-reperfusion injury in hyperacute ischemic stroke rat model.

Endovascular thrombectomy has a recanalization rate over 80%; however, approximately 50% of ischemic stroke patients still experience dependency or mortality. Recently, clinical trials demonstrated the benefits of administering neuroprotective agents prior to endovascular thrombectomy. Additionally, recent studies showed neuroprotective effects of mild hypercapnia in patients resuscitated after cardiac arrest. However, its efficacy in ischemic stroke remains unclear. We aimed to investigate whether carbon dioxide (CO2) per-conditioning has neuroprotective effects in rat models with middle cerebral artery occlusion (MCAO). Rat models received intermittent inhalation of mixed gas during the MCAO period. After surgery, behavioral assessments, infarct size measurement, immunohistochemistry, and western blot analysis were performed. We found CO2 per-conditioning reduced infarct size and neurological deficit. The number of 8-hydroxy-2-deoxyguanosine (8-OHdG) positive cells and matrix metalloproteinase 9 (MMP-9)/platelet derived growth factor receptor beta (PDGFRβ) double positive cells were significantly decreased after CO2 per-conditioning. The expressions of tight junction protein and pericytes survival were preserved. This study underscores mild hypercapnia before reperfusion not only reduces neurologic deficit and infarct size, but also maintains the integrity of the blood-brain barrier and neurovascular unit, alongside mitigating oxidative stress in hyperacute stroke rat models. Therapeutic mild hypercapnia before reperfusion is promising and requires further clinical application.

Case report: Mixed hydrofluoric and nitric acid mist inhalation poisoning

IntroductionHydrofluoric and nitric acids are strongly acidic substances with strong oxidation and are widely used in industrial production. Chemical pneumonia caused by the inhalation of strong acids has occasionally been reported. Severe chemical pneumonia can lead to acute pulmonary edema and life-threatening acute respiratory distress syndrome. The treatment of chemical pneumonia mainly relies on symptomatic and supportive treatment such as anti-inflammatory and anti-infection.Case descriptionThis study reports three cases of chemical pneumonia caused by the inhalation of a mixed hydrofluoric and nitric acid mist during an occupational exposure accident. After appropriate emergency symptomatic treatment, such as oxygenation and excretion promotion, cough, and difficulty in breathing were alleviated but not completely cleared.DiscussionMost of the literature reports damage caused by hydrogen fluoride on the skin and mucosal burns, and reports on lung damage caused by the inhalation of large amounts of hydrogen fluoride gas are relatively rare. Usually in the early stage of this kind of patients can have elevated blood picture, hypoxemia, pulmonary CT inflammatory plaque changes, so as to have obvious respiratory irritation symptoms. When inhaling a large amount of hydrofluorine mixed nitric acid mist, in addition to considering the occurrence of severe pneumonia, we should also be alert to the occurrence of other organ damage and electrolyte disorder.ConclusionAs occupational hydrogen fluoride gas inhalation poisoning often occurs in groups, improving the safety facilities and standard operations of small- and medium-sized enterprises is necessary. For medical workers, it is necessary to be alert to the occurrence of severe toxic pneumonia and severe fluorosis.

Comparison of discussion-based and simulation-based learning methods using the Gas Man® on knowledge of the uptake and distribution of inhalation anesthetics of anesthesia resident: A randomized controlled trial

Abstract Background and Aims: Inhalation anesthetics is basic knowledge that must be mastered by an anesthesiologist. Lack of competencies can result in higher morbidity and mortality in anesthesiology practice. Various learning methods were developed to improve understanding and retention. With the advancement of technology, the utilization of screen-based simulation (SBS) using applications is common, such as the Gas Man® application, to help students understand physiology, pathophysiology, and kinetic inhalation anesthetic agents. The primary objective of this study was to compare the knowledge improvement of anesthesia residents between the simulation-based and discussion-based learning methods on the uptake and distribution of anesthetic inhalation. The secondary objective was to compare the satisfaction levels of participants in both learning methods. Material and Methods: This study is a randomized controlled trial involving anesthesiology and intensive care residents from the Faculty of Medicine, Universitas Indonesia (FKUI) 2022–2023. The participants were randomized into two groups (simulation and discussion groups). A senior attending anesthesiologist led the discussion. The participants answered a pretest, followed by a 1-hour lecture about inhalation gas. Lastly, participants answered a posttest and filled in the satisfaction survey. Statistical analyses used the Mann–Whitney test to compare the two groups. The Wilcoxon test was used to compare the knowledge improvement between the two groups. Results: Thirty-eight residents underwent simulation-based (n = 19) and discussion-based (n = 19) learning methods. The simulation group demonstrated a median (interquartile range) posttest score of 80 (76.67–83.33) compared with the discussion group with a score of 50 (40–66.67) (P value <0.05). More than half of the participants in both groups answered “satisfied.” Conclusion: The simulation-based learning method using the Gas Man® application performed better than the discussion-based learning method on increasing knowledge of the uptake and distribution of inhalation anesthetics in anesthesia residents. Key Message: Simulation-based learning method may improve understanding and retention. This study supported the conclusion that the simulation-based learning method with Gas Man is better than the discussion-based learning method for improving knowledge of the uptake and distribution of inhalation anesthetics.

A Review on Nanotechnological Approaches for the Management of Stored Insect-Pests: Present Scenario and Future Prospects

Approximately 10% to 30% of the stored agricultural produce is damaged out of which 26% is due to insect-pest infestation thus seriously impacting the food security. The infestation also leads to loss of quality and thereby affecting the overall profitability. In absence of enough storage space, usually farmers dispose-off their produce immediately after harvest and thus do not get remunerative prices. For those opting for storage, physical and chemical methods are in vogue to manage the storage insect-pests. Fumigation with chemical pesticides such as methyl bromide and aluminium phosphide is a common method, though it has its own health and environmental risks. Inhalation of phosphine gas released when aluminium phosphide is used could seriously affect human animal health, sometimes leading to deaths. Thus for using these fumigants, strict supervision of government recognized experts is required. Due to their wide usage, some insect-pests have developed resistance against these molecules. Nanotechnology has created numerous new opportunities in agriculture and allied sectors. Insecticide formulations based on nanotechnology could be a viable alternative to toxic chemicals like aluminium phosphide to manage storage insect-pests. In recent years, a variety of formulations including solid nanopesticides, controlled-release formulations, nano-emulsions, and nano-suspensions have been developed possessing different modes of actions and applications. Their small size is a significant advantage because it provides higher insect-body surface area coverage and thus enhanced efficacy as compared to traditional pesticides. Aside from their small size, they are reported to be safe for non-target beneficial organisms. Nano-pesticides can thus prove as effective and eco-friendly alternatives for insect pest control in storage. However, there is a need to establish their safety on the human and animal ecosystems to rule out their ecological hazards over time. In absence of such information, nanopesticides will not be widely accepted despite their other beneficial effects. In this article, an effort is made to review the current status of nano-formulations for the management of storage-insect-pests, the research and extension gaps and ways to bridge the gaps to ensure safe use of the technology for efficient management of postharvest storage losses.

Effect of Pilates exercises on pulmonary function, respiratory muscle strength, and functional capacity in patients with inhalation injury after flame thermal burn: A prospective randomized controlled trial

BackgroundInhalation injury is an acute respiratory tract injury that occurrs by inhalation of smoke, toxic gases, or steam. Early management is needed to reduce its mortality and morbidity. The purpose of this study was to ascertain whether Pilates training could help burn patients with inhalation injury after flame thermal burn in increasing pulmonary function, respiratory muscle strength, and functional ability. MethodsIn this prospective, randomized, controlled trial, sixty participants (26 males and 34 females) with inhalation injury and deep partial-thickness flame burns of 30–40 % total body surface area (TBSA) were randomized in blocks of four, with a 1:1 allocation ratio into two groups: Group A (Pilates Group); received Pilates training plus conventional physical therapy program, and Group B (Control Group); received conventional physical therapy program only. This study was conducted at the Faculty of Physical Therapy's outpatient clinic, Cairo University, 3 sessions/week for 12 weeks. The primary outcome measure was the forced vital capacity (FVC) measured by a spirometer, while the secondary outcome measures were peak expiratory flow rate (PEFR), forced expiratory volume in 1 s (FEV1), FEV1/FVC% assessed by a spirometer, strength of respiratory muscles (maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) assessed by the digital manovacuometer, and the functional capacity evaluated by 6-Minute Walk Test (6-MWT). ResultsA two-way mixed-design MANOVA was used to analyze the results within and between groups. There were no significant differences in demographic data between groups (P > 0.05). There were significant differences in all variables after treatment in group A compared with group B; FVC (95 % CI: 0.38, 1.13) (P = 0.001), FEV1 (95 % CI: 0.39, 0.97) (P = 0.001), FEV1/FVC % (95 % CI: 1.90, 17.19) (P = 0.02), PEFR (95 % CI: 0.47, 0.99) (P = 0.001), MIP (95 % CI: 5.12, 11.44) (P = 0.001), MEP (95 % CI: 2.57, 8.24) (P = 0.001), 6-MWT (95 % CI: 27.22, 54.96) (P = 0.001), FVC (% predicted) (95 % CI: 3.58, 12.58) (P = 0.001), FEV1 (% predicted) (95 % CI: 1.21, 11.11) (P = 0.02), PEFR (% predicted) (95 % CI: 1.33, 10.83) (P = 0.01), MIP (% predicted) (95 % CI: 2.26, 11.72) (P = 0.001) and MEP (% predicted) (95 % CI: 1.33, 10.37) (P = 0.01). ConclusionThe current study demonstrated that a Pilates exercise program in addition to a traditional physical therapy program for 12 weeks significantly improved the pulmonary function (FVC, FEV1, PEFR and FEV1/FEV), strength of respiratory muscles (MIP and MEP), and functional capacity (6-MWT) in patients with inhalation injury after flame burns. These results underscore the importance of including Pilates exercises in the rehabilitation plan for burn patients with inhalation injury. Future studies are needed to evaluate the effect of Pilates exercises on other degrees and TBSA of burn, long-term follow up, and to measure cardiopulmonary parameters.

Clinical characteristics and toxicological spectrum analysis of 493 cases of acute poisoning in children

ObjectiveThis retrospective study aimed to analyze the clinical characteristics and toxicological spectrum of acute poisoning in children treated at our pediatric intensive care unit. The findings provide a basis for the treatment and prevention of acute poisoning in children.MethodsClinical data of hospitalized children aged 0 to14 years with acute poisoning, treated between January 2015 and December 2023, were collected and analyzed. The analysis included the types of poisoning, sex and age distribution of children, routes and causes of poisoning, time from poisoning to medical consultation, length of hospital stays, and treatment outcomes.ResultsAmong the 493 cases of acute poisoning in children, pesticide poisoning (n = 252, 51.1%) was the most common type, followed by medication poisoning (n = 182, 36.9%). Chemical poisoning accounted for 7.7% (n = 38), while food poisoning and inhalation of harmful gases accounted for 3.0% (n = 15) and 1.2% (n = 6), respectively. The main route of poisoning was oral ingestion (n = 477, 96.8%), while accidental ingestion accounted for a large proportion (n = 379, 79.4%), and adolescents aged 11 to 14 years accounted for 20.6% (n = 98).Apart from the predominance of girls attempting suicide by self-administering antipsychotic medications (n = 88, 75.9%) due to depression, there was no significant difference in sex distribution among other types of poisoning children. The highest incidence of poisoning except children who self-administer antipsychotic drugs occurred in children aged 1–3 years (n = 267, 54.2%) and 8–14 years (n = 135, 27.4%), with the highest proportion in the preschool age group. The average time from poisoning to medical consultation was 33.4 ± 54.9 h, and majority of children received treatment within 48 h after poisoning (n = 423, 85.8%). The overall effective treatment rate was 96.8%.ConclusionAcute poisoning in children has complex and diverse causes, with accidental ingestion being the main route. Prevention should be emphasized, including strengthening child safety education and improving parental supervision. Moreover, psychological health education is crucial for adolescents during their puberty. In the event of acute poisoning, prompt medical consultation and appropriate treatment are necessary to mitigate adverse outcomes.

Pilot Feasibility and Safety Study of Hydrogen Gas Inhalation in Locally Advanced Head and Neck Cancer Patients

Pilot Feasibility and Safety Study of Hydrogen Gas Inhalation in Locally Advanced Head and Neck Cancer Patients

Measurement and modeling of xenon gas transfer in the human brain with 1H and hyperpolarized 129Xe MRI

BackgroundThe feasibility of imaging hyperpolarized 129Xe dissolved in brain tissue following inhalation of xenon gas in the lungs has recently been demonstrated in humans. The image contrast in 129Xe brain MRI represents a combination of factors, including regional perfusion, polarization decay and gas transfer rate across the blood-brain barrier. PurposeTo investigate the repeatability of hyperpolarized 129Xe brain MRI in healthy normal individuals and to identify the dominant mechanisms of image contrast by assessing voxel-wise correlation between HP 129Xe brain MRI and models of 129Xe brain uptake derived from 1H arterial spin labeling (ASL) perfusion mapping. Materials and MethodsTo assess repeatability, 3 sets of hyperpolarized 129Xe brain images were acquired from 5 healthy volunteers. Quantitative maps of the human brain, including cerebral blood flow, volume and predicted xenon uptake, were derived from 1H arterial spin labeling and T2-weighted MRI. These maps were then spatially cross-correlated with hyperpolarized 129Xe brain MRI. ResultsSignal to noise ratios of 8.7–17.7 were observed across volunteers for a voxel size of 8 × 8 × 50 mm3 with intra-subject repeatability of between 6 and 29 %. Hyperpolarized 129Xe brain images showed voxel-wise correlations with cerebral blood flow (R = 0.32 to 0.62), volume (R = 0.33 to 0.63) and predicted xenon uptake (R = 0.34 to 0.63), but did not correlate with arterial transit time (R = 0.05 to 0.26). ConclusionVoxel-wise cross correlation between 129Xe and 1H ASL suggests that the regional quantity of dissolved xenon delivered by cerebral blood flow is the dominant mechanism of image contrast in HP 129Xe brain MRI, assuming normal blood-brain barrier function. Combining 1H and 129Xe brain MRI provides new opportunities to quantitatively investigate brain pathophysiology and function.

Natural hydrogen gas and engineered microalgae prevent acute lung injury in sepsis

BackgroundHydrogen gas and microalgae both exist in the natural environment. We aimed to integrate hydrogen gas and biology nano microalgae together to expand the treatment options in sepsis. MethodsPhosphoproteomics, metabolomics and proteomics data were obtained from mice undergoing cecum ligation and puncture (CLP) and inhalation of hydrogen gas. All omics analysis procedure were accordance with standards. Multi R packages were used in single cell and spatial transcriptomics analysis to identify primary cells expressing targeted genes, and the genes’ co-expression relationships in sepsis related lung landscape. Then, network pharmacology method was used to identify candidate drugs. We used hydrophobic-force-driving self-assembly method to construct dihydroquercetin (DQ) nanoparticle. To cooperate with molecular hydrogen, ammonia borane (B) was added to DQ surface. Then, Chlorella vulgaris (C) was used as biological carrier to improve self-assembly nanoparticle. Vivo and vitro experiments were both conducted to evaluate anti-inflammation, anti-ferroptosis, anti-infection and organ protection capability. ResultsAs a result, we identified Esam and Zo-1 were target phosphorylation proteins for molecular hydrogen treatment in lung. Ferroptosis and glutathione metabolism were two target pathways. Chlorella vulgaris improved the dispersion of DQB and reconstructed morphological features of DQB, formed DQB@C nano-system (size = 307.3 nm, zeta potential = −22mv), with well infection-responsive hydrogen release capability and biosafety. In addition, DQB@C was able to decrease oxidative stress and inflammation factors accumulation in lung cells. Through increasing expression level of Slc7a11/xCT and decreasing Cox2 level to participate with the regulation of ferroptosis. Also, DQB@C played lung and multi organ protection and anti-inflammation roles on CLP mice. ConclusionOur research proposed DQB@C as a novel biology nano-system with enormous potential on treatment for sepsis related acute lung injury to solve the limitation of hydrogen gas utilization in clinics.

Inhalation of Hydrogen-rich Gas before Acute Exercise Alleviates Exercise Fatigue: A Randomized Crossover Study.

Hydrogen, as an antioxidant, may have the potential to mitigate fatigue and improve selected oxidative stress markers induced by strenuous exercise. This study focused on a previously unexplored approach involving pre-exercise inhalation of hydrogen-rich gas (HRG). Twenty-four healthy adult men first completed pre-laboratories to determine maximum cycling power (Wmax) and maximum cycling time (Tmax). Then they were subjected to ride Tmax at 80% Wmax and 60-70 rpm on cycle ergometers after inhaled HRG or placebo gas (air) for 60-minute in a double-blind, counterbalanced, randomized, and crossover design. The cycling frequency in the fatigue modeling process and the rating of perceived exertion (RPE) at the beginning and end of the ride were recorded. Before gas inhalation and after fatigue modeling, visual analog scale (VAS) for fatigue and counter-movement jump (CMJ) were tested, and blood samples were obtained. The results showed that compared to a placebo, HRG inhalation induced significant improvement in VAS, RPE, the cycling frequency during the last 30 seconds in the fatigue modeling process, the ability to inhibit hydroxyl radicals, and serum lactate after exercise (p<0.028), but not in CMJ height and glutathione peroxidase activity. The cycling frequency during the last 30 seconds of all other segments in the fatigue modeling process was within the range of 60-70 rpm. In conclusion, HRG inhalation prior to acute exercise can alleviate exercise-induced fatigue, maintain functional performance, and improve hydroxyl radical and lactate levels.

Release of ATP in the lung evoked by inhalation of irritant gases in rats.

Adenosine triphosphate (ATP) can be released into the extracellular milieu from various types of cells in response to a wide range of physical or chemical stresses. In the respiratory tract, extracellular ATP is recognized as an important signal molecule and trigger of airway inflammation. Chlorine (Cl2), sulfur dioxide (SO2), and ammonia (NH3) are potent irritant gases and common industrial air pollutants due to their widespread uses as chemical agents. This study was carried out to determine if acute inhalation challenges of these irritant gases, at the concentration and duration simulating the accidental exposures to these chemical gases in industrial operations, triggered the release of ATP in the rat respiratory tract; and if so, whether the level of ATP in bronchoalveolar lavage fluid (BALF) evoked by inhalation challenge of a given irritant gas was elevated by chronic allergic airway inflammation. Our results showed: 1) inhalation of these irritant gases caused significant increases in the ATP level in BALF, and the magnitude of evoked ATP release was in the order of Cl2 > SO2 > NH3. 2) Chronic airway inflammation induced by ovalbumin-sensitization markedly elevated the ATP level in BALF during baseline (breathing room air) but did not potentiate the release of ATP in the lung triggered by inhalation challenges of these irritant gases. These findings suggested a possible involvement of the ATP release in the lung in the regulation of overall airway responses to acute inhalation of irritant gases and the pathogenesis of chronic allergic airway inflammation.NEW & NOTEWORTHY Extracellular adenosine triphosphate (ATP) is a contributing factor and signaling molecule of airway inflammation. This study demonstrated for the first time that the ATP release in the lung was markedly elevated after acute inhalation challenges of three common industrial air pollutants; the order of the response magnitude was chlorine > sulfur dioxide > ammonia. These findings provided new information and improved our understanding of the adverse pulmonary effects caused by accidental inhalation exposures to these irritant gases.

Quantitative assessment of chlorine gas inhalation injury based on endoscopic OCT and spectral encoded interferometric microscope imaging with deep learning.

Chlorine exposure can cause severe airway injuries. While the acute effects of chlorine inhalation are well-documented, the structural changes resulting from the post-acute, high-level chlorine exposure remain less understood. Airway sloughing is one of the standards for doctors to evaluate the lung function. Here, we report the application of a high-resolution swept-source optical coherence tomography system to investigate the progression of injury based on airway sloughing evaluation in a chlorine inhalation rabbit model. This system employs a 1.2mm diameter flexible fiberoptic endoscopic probe via an endotracheal tube to capture in vivo large airway anatomical changes before and as early as 30minafter acute chlorine exposure. We conducted an animal study using New Zealand white rabbits exposed to acute chlorine gas (800 ppm, 6min) during ventilation and monitored them using optical coherence tomography (OCT) for 6h. To measure the volume of airway sloughing induced by chlorine gas, we utilized deep learning for the segmentation task on OCT images. The results showed that the volume of chlorine induced epithelial sloughing on rabbit tracheal walls initially increased, peaked around 30min, and then decreased. Furthermore, we utilized a spectral encoded interferometric microscopy system to study ex vivo airway cilia beating dynamics based on Doppler shift, aiding in elucidating how chlorine gas affects cilia beating function. Cilia movability and beating frequency were decreased because of the epithelium damage. This quantitative approach has the potential to enhance the diagnosis and monitoring of injuries from toxic gas inhalation and to evaluate the efficacy of antidote treatments for these injuries.

Trends in chlorine and chloramine gas exposures reported to United States poison centers

Introduction Chlorine and chloramine gas inhalation can occur when household cleaners are mixed. The increased emphasis on disinfecting practices during the COVID-19 pandemic may have contributed to an increase in chlorine and chloramine gas exposures in the United States, which has not been studied. Methods In a retrospective review, reported data on chlorine and chloramine gas exposures in the National Poison Data System were collected from January 1, 2015, to December 31, 2022. Data included demographics and exposure details, including location, dose, formulation, co-exposures, treatments, and outcomes. Demographic analyses and descriptive statistics were conducted. Results During the study period, 85,104 total exposures to chlorine and chloramine gas were reported, consisting of 79,281 isolated exposures and 5,823 co-exposures. Total exposures increased by 61% from 8,385 in 2015 to 13,503 in 2022, with the largest increase of 38.3% occurring from 2019 to 2020. Total exposures remained increased through 2022 with no return to pre-pandemic levels. Most exposures occurred in “own residence” (n = 72,213, 84.9%), with a larger proportion of exposures occurring at home peri-pandemic versus pre-pandemic (88.4% versus 81.7%). One percent (n = 1,030) of exposures were admitted to a non-critical care unit, 0.73% (n = 619) were admitted to a critical care unit, and 0.03% (n = 26) resulted in death. Discussion The onset of the COVID-19 pandemic and increased emphasis on cleaning practices were likely contributing factors to the marked increase in exposures in 2020, which persisted through 2022. Cleaning practices that developed during the beginning of the pandemic likely persisted despite returning to more normal daily routines, which may explain the ongoing increase in reported exposures. Most reported exposures were unintentional, mild in symptomatology, and required the use of non-invasive therapies, if any. Conclusions Future efforts should focus on public education on the safe use of cleaning products to prevent exposure to toxic chlorine and chloramine gases.

Impact of Earthquakes on Lung Health.

Earthquakes are catastrophic natural disasters that cause extensive damage to infrastructure and disrupt the lives of millions worldwide. Beyond the immediate physical and psychological damage caused by earthquakes, these events can significantly impact respiratory health. The inhalation of dust, smoke, particulates, toxic gases, and asbestos exposure can lead to various respiratory health pathologies. These include respiratory infections, exacerbations of pre-existing respiratory diseases, chest traumas, and pulmonary and venous thromboembolism. Longitudinal studies are necessary to assess the long-term respiratory health effects in affected populations. By addressing these knowledge gaps, future mitigation strategies and preparedness measures can be developed to minimize the respiratory health impacts of earthquakes and improve the well-being of affected communities. Robust building infrastructure and comprehensive earthquake preparedness are emerging as the most important determinants for not only mitigating building collapse but also significantly reducing the potential health impacts that follow. This comprehensive review aims to provide a systematic overview of the lung health impacts of earthquakes. It highlights the need for further research to identify specific pollutants, air contaminants, and environmental factors contributing to respiratory health issues following earthquakes.

Hypoxic irreversible brain cells damage, associated risk factors and antihypoxants

It is reported that in the final stage of many diseases the immediate cause of biological death in humans and warm-blooded animals is hypoxic irreversible damage to brain cells. This explains the fact that to prevent biological death in all critical conditions without exception, inhalation with breathing gases containing oxygen has long been successfully used. This is also why oxygenation of the blood is considered one of the main conditions for preserving human life in all critical situations and forms the basis of emergency medical care in the intensive care unit. However, inhalation of oxygen gas and increasing blood oxygen saturation should be carried out as early as possible, and more precisely - before the onset of the stage of hypoxic irreversible damage in brain cells. The fact is that after the onset of irreversible damage brain cells die even in the presence of oxygen. In this connection, the mechanisms of adaptation of the organism to oxygen deficiency play a great role for longer preservation of brain cells viability and human life in conditions of hypoxemia. In order to increase resistance to hypoxemia, antihypoxants are traditionally used. But they can preserve the viability of brain cells not always, but only if they are introduced into the body before the onset of hypoxic irreversible damage to brain cells and in the case of unused reserves of adaptation to hypoxemia in the body. Risk factors of hypoxic irreversible damage of brain cells are indicated, among which excessively long duration of hypoxemia and hyperthermia are emphasized. It is shown that the most important circumstance for the development of hypoxic irreversible damage of brain cells is not so much the degree of hypoxemia as the degree of hypoxia of brain tissue and its duration, which exceeds the period of human resistance to hypoxia. It has been shown that human resistance to hypoxia can be assessed using the Stange test. It has been reported that fever and local cerebral hyperthermia decrease, and hibernation and local cerebral hypothermia increase, the resistance of brain cells to hypoxia. In this regard, recommendations not only to eliminate fever and local inflammatory processes in the head, but also recommendations to reduce brain temperature are highly appropriate to improve resistance to hypoxia. It is pointed out that among the methods of local therapeutic hypothermia, targeted temperature management is the most advanced. In addition, it is reported that in recent years a new group of promising antihypoxants - alkaline solutions of hydrogen peroxide - has been created. It is shown that hydrogen peroxide is able to decompose very quickly into water and oxygen gas under the action of catalase, which is found in all tissues. The peculiarities of using alkaline solutions of hydrogen peroxide as antihypoxants we all have to study in the future.

Acute Neurobehavioral and Glial Responses to Explosion Gas Inhalation in Rats.

Military personnel, firefighters, and fire survivors exhibit a higher prevalence of mental health conditions such as depression and post-traumatic stress disorder (PTSD) compared to the general population. While numerous studies have examined the neurological impacts of physical trauma and psychological stress, research on acute neurobehavioral effects of gas inhalation from explosions or fires is limited. This study investigates the early-stage neurobehavioral and neuronal consequences of acute explosion gas inhalation in Sprague-Dawley rats. Rats were exposed to simulated explosive gas and subsequently assessed using behavioral tests and neurobiological analyses. The high-dose exposure group demonstrated significant depression-like behaviors, including reduced mobility and exploration. However, neuronal damage was not evident in histological analyses. Immunofluorescence revealed increased density of radial glia and oligodendrocytes in specific brain regions, suggesting hypoxia and axon damage induced by gas inhalation as a potential mechanism for the observed neurobehavioral changes. These findings underscore the acute impact of explosion gas inhalation on mental health, highlighting the habenula and dentate gyrus of hippocampus as the possible target regions. The findings are expected to support early diagnosis and treatment strategies for brain injuries caused by explosion gas, offering insights into early intervention for depression and PTSD in affected populations.

229 TCTR20230627002: Feasibility of hydrogen gas inhalation in chemoradiation for head and neck cancer

229 TCTR20230627002: Feasibility of hydrogen gas inhalation in chemoradiation for head and neck cancer

Recurrence-free survival after curative resection of non-small cell lung cancer between inhalational gas anesthesia and propofol-based total intravenous anesthesia: a multicenter, randomized, clinical trial (GAS TIVA trial): protocol description

BackgroundSurgery is the primary treatment for non-small cell lung cancer (NSCLC), but microscopic residual disease may be unavoidable. Preclinical studies have shown that volatile anesthetics might suppress host immunity and promote a pro-malignant environment that supports cancer cell proliferation, migration, and angiogenesis, whereas propofol may preserve cell-mediated immunity and inhibit tumor angiogenesis. However, clinical evidence that propofol-based total intravenous anesthesia (TIVA) can reduce tumor recurrence after curative resection remains inconsistent due to the retrospective observational nature of previous studies. Therefore, we will test the hypothesis that the recurrence-free survival (RFS) after curative resection of NSCLC is higher in patients who received TIVA than volatile anesthetics (GAS) in this multicenter randomized trial.MethodsThis double-blind, randomized trial will enroll patients at 22 international sites, subject to study registration, institutional review board approval, and patient written informed consent. Eligible patients are adult patients undergoing lung resection surgery with curative intent for NSCLC. Exclusion criteria will be contraindications to study drugs, American Society of Anesthesiologists physical status IV or higher, or preexisting distant metastasis or malignant tumor in other organs. At each study site, enrolled subjects will be randomly allocated into the TIVA and GAS groups with a 1:1 ratio. This pragmatic trial does not standardize any aspect of patient care. However, potential confounders will be balanced between the study arms. The primary outcome will be RFS. Secondary outcomes will be overall survival and complications within postoperative 7 days. Enrollment of 5384 patients will provide 80% power to detect a 3% treatment effect (hazard ratio of 0.83) at alpha 0.05 for RFS at 3 years.DiscussionConfirmation of the study hypothesis would demonstrate that a relatively minor and low-cost alteration in anesthetic management has the potential to reduce cancer recurrence risk in NSCLC, an ultimately fatal complication. Rejection of the hypothesis would end the ongoing debate about the relationship between cancer recurrence and anesthetic management.Trial registrationThe study protocol was prospectively registered at the Clinical trials (https://clinicaltrials.gov, NCT06330038, principal investigator: Hyun Joo Ahn; date of first public release: March 25, 2024) before the recruitment of the first participant.

A Comparative Investigation of the Pulmonary Vasodilating Effects of Inhaled NO Gas Therapy and Inhalation of a New Drug Formulation Containing a NO Donor Metabolite (SIN-1A).

Numerous research projects focused on the management of acute pulmonary hypertension as Coronavirus Disease 2019 (COVID-19) might lead to hypoxia-induced pulmonary vasoconstriction related to acute respiratory distress syndrome. For that reason, inhalative therapeutic options have been the subject of several clinical trials. In this experimental study, we aimed to examine the hemodynamic impact of the inhalation of the SIN-1A formulation (N-nitroso-N-morpholino-amino-acetonitrile, the unstable active metabolite of molsidomine, stabilized by a cyclodextrin derivative) in a porcine model of acute pulmonary hypertension. Landrace pigs were divided into the following experimental groups: iNO (inhaled nitric oxide, n = 3), SIN-1A-5 (5 mg, n = 3), and SIN-1A-10 (10 mg, n = 3). Parallel insertion of a PiCCO system and a pulmonary artery catheter (Swan-Ganz) was performed for continuous hemodynamic monitoring. The impact of iNO (15 min) and SIN-1A inhalation (30 min) was investigated under physiologic conditions and U46619-induced acute pulmonary hypertension. Mean pulmonary arterial pressure (PAP) was reduced transiently by both substances. SIN-1A-10 had a comparable impact compared to iNO after U46619-induced pulmonary hypertension. PAP and PVR decreased significantly (changes in PAP: -30.1% iNO, -22.1% SIN-1A-5, -31.2% SIN-1A-10). While iNO therapy did not alter the mean arterial pressure (MAP) and systemic vascular resistance (SVR), SIN-1A administration resulted in decreased MAP and SVR values. Consequently, the PVR/SVR ratio was markedly reduced in the iNO group, while SIN-1A did not alter this parameter. The pulmonary vasodilatory impact of inhaled SIN-1A was shown to be dose-dependent. A larger dose of SIN-1A (10 mg) resulted in decreased PAP and PVR in a similar manner to the gold standard iNO therapy. Inhalation of the nebulized solution of the new SIN-1A formulation (stabilized by a cyclodextrin derivative) might be a valuable, effective option where iNO therapy is not available due to dosing difficulties or availability.

Hydrogen-Rich Gas Enhanced Sprint-Interval Performance: Metabolomic Insights into Underlying Mechanisms.

(1) Background: The diversity of blood biomarkers used to assess the metabolic mechanisms of hydrogen limits a comprehensive understanding of its effects on improving exercise performance. This study evaluated the impact of hydrogen-rich gas (HRG) on metabolites following sprint-interval exercise using metabolomics approaches, aiming to elucidate its underlying mechanisms of action. (2) Methods: Ten healthy adult males participated in the Wingate Sprint-interval test (SIT) following 60 min of HRG or placebo (air) inhalation. Venous blood samples were collected for metabolomic analysis both before and after gas inhalation and subsequent to completing the SIT. (3) Results: Compared with the placebo, HRG inhalation significantly improved mean power, fatigue index, and time to peak for the fourth sprint and significantly reduced the attenuation values of peak power, mean power, and time to peak between the first and fourth. Metabolomic analysis highlighted the significant upregulation of acetylcarnitine, propionyl-L-carnitine, hypoxanthine, and xanthine upon HRG inhalation, with enrichment pathway analysis suggesting that HRG may foster fat mobilization by enhancing coenzyme A synthesis, promoting glycerophospholipid metabolism, and suppressing insulin levels. (4) Conclusions: Inhaling HRG before an SIT enhances end-stage anaerobic sprint capabilities and mitigates fatigue. Metabolomic analysis suggests that HRG may enhance ATP recovery during interval stages by accelerating fat oxidation, providing increased energy replenishment for late-stage sprints.