Inhalation Pneumonitis Caused by Nebulized Hydrogen Peroxide.

Hydrogen peroxide is a chemical commonly used as a household antiseptic for cleaning and disinfecting. No cases of acute hydrogen peroxide inhalation-induced lung injury are previously described. We present a case of acute chemical pneumonitis caused by mixing hydrogen peroxide in a nighttime continuous positive airway pressure device's humidifier used for obstructive sleep apnea to prevent COVID-19 infection. The patient endorsed mixing hydrogen peroxide with distilled water in his nighttime continuous positive airway pressure device's humidifier at a ratio of 1:3-1:2 for the previous week before admission based on a friend's advice in preventing COVID-19. The presenting chest X-ray showed new multifocal consolidations with interstitial markings and alveolar edema throughout both lungs. Chest computed tomography (CT) imaging demonstrated multifocal, bilateral, hazy consolidations with increased interstitial markings and bilateral pleural effusions. The patient was subsequently initiated on systemic glucocorticoid therapy, significantly improving hypoxemia and dyspnea. Inhalation of hydrogen peroxide may produce acute pneumonitis distinct from what has been described previously with chronic inhalation. Given this case, systemic glucocorticoid therapy may be considered a viable treatment option for acute hydrogen peroxide-associated inhalation lung injury causing pneumonitis.

Evaluating the effect of gargling with hydrogen peroxide and povidone-iodine on salivary viral load of SARS-CoV-2: A pilot randomized clinical trial.

Background and Aim: This study evaluates the salivary viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in hospitalized patients and outpatients before and after gargling with 1% hydrogen peroxide and 0.25% povidone-iodine in comparison with normal saline. Patients and Methods: This clinical trial was conducted on 120 participants with laboratory-confirmed coronavirus disease 2019 (COVID-19) in two groups: outpatients (n = 60) and hospitalized patients (n = 60). In each group, the patients were randomly divided into three subgroups of 20 based on their given mouthwash for gargling (hydrogen peroxide, povidone-iodine, or normal saline). Two saliva samples were taken from each patient: the first one before gargling and the second one 10 minutes after gargling 10 ml of the respected mouthwashes for 30 seconds. The TaqMan real-time polymerase chain reaction (PCR) amplification of SARS-CoV-2 was used to measure the viral load. Results: Saliva samples from 46% of patients were positive for coronavirus before gargling the mouthwashes. The percentage of patients with an initial positive saliva sample was significantly higher in the outpatient group (83.3%) than in the hospitalized group (5.4%) (P = 0.01). According to the findings, gargling any mouthwash similar to saline did not reduce the viral load (P > 0.05). Conclusion: The saliva of COVID-19 patients in the initial stage of the disease was more likely to contain SARS-CoV-2 than the saliva of the hospitalized patients. Gargling hydrogen peroxide or povidone-iodine did not reduce the salivary SARS-CoV-2 viral load.

Coronavirus Disease (COVID-19) Possible Transmission Routes and Alleviation Strategies

Coronavirus disease is a contagious respiratory ailment that has spread significantly around the world. Most cases of COVID-19 are spread from person to person by coming into contact with respiratory droplets that are released when an infected person coughs or sneezes. In this manuscript, we have highlighted the possible transmission of COVID-19 through food, water, air and paper. In the case of food, we have extensively covered the transmission of COVID-19 through meat, frozen foods, food packaging and food market along with the incidences worldwide. In the nextsection, we have highlighted the different components of air which are responsible for the transmission and also covered its relation with PM 2.5 incidence. The SARS-CoV-2 was isolated from sewage water/wastewater of various countries namely the United States, India, Australia, Netherlands and France signifying that wastewater can be a mode of virus transmission. The paper circulation by the infected COVID-19 patients can also be a virus conveyance route. It can be concluded that SARS-CoV-2 can therefore be transmitted indirectly through food via the workers involved in food packing or food marts.By following general safety precautions (wearing masks, using hand sanitisers, cleaning and disinfecting contact surfaces, and avoiding close contact), heating and using chemicals like ethanol (67-71%), sodium hypochlorite (0.1%) and hydrogen peroxide (0.5%) on environmental surfaces, along with vaccination, it is possible to reduce the spread of the SARS-CoV-2 virus.Copyright © 2023 The International Journal of Pharmaceutical Research and Allied Sciences (IJPRAS).

Post-Covid mucormycosis presenting as retropharyngeal abscess: a rare case report

Background: Post-Covid retropharyngeal mucormycosis is a rare presentation, and no case has been reported in literature until date. Case presentation: A-32-year-old female post Covid presented to our OPD with history of dysphagia and with a history of steroid intake. Radiology confirmed it as retropharyngeal abscess. Endoscopic-guided aspiration was done. HPE (histopathological examination) revealed classic broad aseptate hyphae of mucormycosis. Patient was managed conservatively with broad-spectrum antifungal. Conclusion(s): Retropharyngeal mucormycosis is a rare entity in Covid era. Rapid diagnosis and management are needed to save life of an individual, or results could be fatal.Copyright © 2022, The Author(s).

Assessing Mask Integrity and Fit of N95 Masks after 5 Cycles of Decontamination and Reuse in a Simulated Clinical Setting

Aim: To evaluate the effect of decontamination and reuse on N95 masks. Background(s): The coronavirus disease (COVID-19) pandemic has strained the global availability of masks. Such shortage represents a threat to healthcare workers (HCWs). Mask reprocessing and reuse may alleviate the shortage. Many laboratory studies have proven the effectiveness and feasibility of decontaminating N95 masks. However, very few had HCWs wearing them between cycles of decontamination. Our study evaluated mask integrity (assessed by qualitative mask fitting [QMF], as well as technical measures like bacterial filtration efficacy [BFE]) through five cycles of decontamination using four different modalities - steam, moist heat (MH), UV-C irradiation (UVCI), and hydrogen peroxide vaporization (HPV). Method(s): Each study cycle involved a HCW wearing a N95 mask for two hours, followed by the assigned decontamination process, and then a QMF. This was repeated for a maximum of 5 cycles, as long as the wearer passed QMF. 40 HCWs were recruited for each of the four decontamination modalities. The technical measures of mask integrity assessed were: BFE, Particulate Filtration Efficiency (PFE), Pressure Drop and Splash Resistance. Result(s): 60.6% (HPV) to 77.5% (MH) of the masks passed five cycles of wear and decontamination, as assessed by the wearers passing QMF all five times. MH-decontaminated masks retained all technical measures of integrity through all 5 cycles. HPV reduced masks' BFE after the fourth cycle while UVCI tended to increase the Pressure Drop. Conclusion(s): The results suggest that MH is a promising method for decontaminating N95 masks without compromising fit and integrity. [Figure presented] [Table presented]Copyright © 2023 Southern Society for Clinical Investigation.

Antiviral effect of oral antiseptic solutions commonly used in dentistry practice: A scoping review

Objective: The purpose of this scoping review is to show the evidence available in the literature and provide an overview of the antimicrobial-containing mouthwashes for reducing viral load in order to group the most up-to-date information and make it more accessible to dentists. Design(s): A structured electronic search in PubMed (Medline), LILACS, EMBASE and EBSCO without temporal restriction was performed. The studies were selected based on their title, and full reading following a pre-established order based on the inclusion and exclusion criteria. The included studies were those that analyzed the effect of viral load reduction by mouthwashes, primary studies, no reviews and in Spanish, English or Portuguese. Result(s): The search resulted in 1881 articles, at the end of the exclusion of duplicates and selection, 71 articles were included in this scoping review. The substances most commonly found were chlorhexidine (CHX), povidone-iodine (PVP-I), essential oils (EO), cetylpyridinium chloride (CPC), hydrogen peroxide (H2O2) and other substances (OTHERS). Conclusion(s): Of all the mouthwashes analyzed, the Essential oils, Cetylpyridinium Chloride and Povidone-iodine, showed antiviral potential against common viruses present in the oral cavity, with no significant side effects in short-term use, and are viable options for use as a pre-procedure in clinical routine against SARS-CoV-2 and other types of viruses. The other solutions need further studies to determine their effect and confirm their clinical use.Copyright © 2023

Oxidation and "Unconventional” Approaches to Infection

Nonpharmacological approaches can be useful to control infectious diseases. Historically infection has been successfully managed with oxidation therapy methods that support the body's own innate defenses. Several modalities include ozone and hyperbaric oxygen therapy, ultraviolet blood irradiation (UBI), intravenous hydrogen peroxide, and ascorbate therapies. Oxidation therapies are virtually 100% safe, and repeatedly reported as highly and quickly effective in quelling infection (bacterial and viral) either as stand-alone therapies or adjunctive with drugs. They are directly and indirectly germicidal, and modulate the immune system via pro-oxidant signaling molecules. Oxidation therapies especially enhance oxygen delivery and metabolism, critical for all infection defenses. Ozone has remitted Ebola, COVID-19, and bacterial infections. UBI defeated most preantibiotic era infections in hospitals. Not being drug therapy, the effects of oxidation defenses, used by planetary animal life for millions of years, are not diminished by antibiotic-resistant organisms. Oxidation, depending on delivery method, can be very inexpensive and third world adaptable. This chapter summarizes the use of these key modalities, by exploring known published literature. © 2022 Elsevier Inc. All rights reserved.

Recovery of Platinum and Palladium from Spent Automotive Catalysts: Study of a New Leaching System Using a Complete Factorial Design

The recovery of materials and energy from end-of-life products is increasingly a fundamental factor in the sustainable development of various countries. Recovering metals from different types of waste is not only a practice in support of the environment, but is also a profitable economic activity. For this reason, exhausted automotive catalysts can become renewable sources of critical raw materials such as Pt, Pd, and Rh. However, recovering Pt and Pd from spent catalysts through an efficient, economical, and green method remains a challenge. This article presents a new leaching process for the hydrometallurgical recovery of Pt and Pd from exhausted automotive catalysts. The leaching solution consists of an aqueous mixture of hydrochloric acid, two organic acids (citric acid and acetic acid) and hydrogen peroxide. A complete factorial plan on two levels (2k) was performed in order to evaluate the main effects of the analyzed factors and their interactions. The factors that were presumed to be the most influential on the leaching of Pt and Pd were the concentrations of the different reagents and the reaction time. The optimal circumstances for achieving the largest recovery (over 80% Pt and 100% Pd) were achieved using the following conditions: a concentration of HCl of 5 M, a concentration of H2O2 of 10% wt./vol., a concentration of C2H4O2 of 10%vol./vol., and a reaction time of 3 h.

Electrochemical sensing of dual biomolecules in live cells and whole blood samples: A flexible gold wire-modified copper-organic framework-based hybrid composite.

For clinical research, the precise measurement of hydrogen peroxide (H2O2) and glucose (Glu) is of paramount importance, due to their imbalanced concentrations in blood glucose, and reactive oxygen species (ROS) play a huge role in COVID-19 viral disease. It is critical to construct and develop a simple, rapid, flexible, long-term, and sensitive detection of H2O2 and glucose. In this paper, we have developed a unique morphological structure of MOF(Cu) on a single-walled carbon nanotube-modified gold wire (swnt@gw). Highly designed frameworks with nanotube composites enhance electron rate-transfer behavior while extending conductance and electroactive surface area.The composite sensing system delivers wide linear-range concentrations, low detection limit, and interference-free performance in co-existence with other biomolecules and metal ions. Endogenous quantitative tracking of H2O2 was performed in macrophage live-cells with the help of a strong stimulator lipopolysaccharide.The composite device was effectively utilized for the measurement of H2O2 and glucose in turbid samples of whole blood and milk samples without a pretreatment process. The practical results of biofluids showed favorable voltammetric results and acceptance recovery percentage levels between 97.49 and 98.88%. Finally, a flexible MOF-based hybrid system may provide a suitable detection platform in the construction of electro-biosensors and hold potential promise for clinical-sensory applications.

Continuous Glucose Monitoring in Hypoxic Environments Based on Water Splitting-Assisted Electrocatalysis

Conventional enzyme-based continuous glucose sensors in interstitial fluid usually rely on dissolved oxygen as the electron-transfer mediator to bring electrons from oxidase to electrode while generating hydrogen peroxide. This may lead to several problems. First, the sensor may provide biased detection results owing to fluctuation of oxygen in interstitial fluid. Second, the polymer coatings that regulate the glucose/oxygen ratio can affect the dynamic response of the sensor. Third, the glucose oxidation reaction continuously produces corrosive hydrogen peroxide, which may compromise the long-term stability of the sensor. Here, we introduce an oxygen-independent nonenzymatic glucose sensor based on water splitting-assisted electrocatalysis for continuous glucose monitoring. For the water splitting reaction (i.e., hydrogen evolution reaction), a negative pretreatment potential is applied to produce a localized alkaline condition at the surface of the working electrode for subsequent nonenzymatic electrocatalytic oxidation of glucose. The reaction process does not require the participation of oxygen;therefore, the problems caused by oxygen can be avoided. The nonenzymatic sensor exhibits acceptable sensitivity, reliability, and biocompatibility for continuous glucose monitoring in hypoxic environments, as shown by the in vitro and in vivo measurements. Therefore, we believe that it is a promising technique for continuous glucose monitoring, especially for clinically hypoxic patients.

A Comprehensive Review on the Medicinal Benefits of Honey with an Emphasis on Unani Medicine

Background: Honey has been used medicinally in folk medicine since the dawn of civili-zation. It is a necessary component of medicine and food in a wide variety of cultures. It has been used in Unani Medicine for centuries to treat a variety of ailments. Objective(s): This review article aims to explore the medicinal characteristics of honey in view of Unani and modern concepts, highlight its potential in the treatment of the ailments stated in Unani medical literature, and also explore the relevant evidence-based phytochemistry, pharmacological, and clinical data. Method(s): The authors searched classical texts exhaustively for information on the temperament (Mizaj), pharmacological activities, mechanism of action, and therapeutic benefits of honey. Addition-ally, a comprehensive search of internet databases was conducted to compile all available information on the physicochemical, phytochemical, and pharmacological properties of this compound. Result(s): Evidence suggests that honey contains about 180 different types of various compounds, including carbohydrates, proteins, enzymes, flavonoids, and other chemical substances. In Unani classical literature, it exerts important pharmacological actions besides its immense nutritional signifi-cance. Unani physicians advocated many tested/experimented prescriptions and formulations, which still have their relevance in the amelioration of various diseases. Conclusion(s): This analysis concludes that honey has been successfully utilized in Unani medicine for centuries to treat a variety of maladies and is a potential natural source of remedy for a variety of medical disorders. Future research on honey should include a combination of Unani and modern principles.Copyright © 2023 Bentham Science Publishers.

The effect of current infection control procedures and application times on the dimensional stability of dental impression materials

Aims: In this study, the effects of different disinfection and sterilization methods and their application duration on the dimensional stability of impression materials were evaluated. Methods: Two impression materials, condensation (CS) and addition silicone (VPS), disinfectants with 5.25% sodium hypochlorite (NaOCl) immersion, 3% hydrogen peroxide immersion and steam autoclave were selected. Disc-shaped samples (n=112) were obtained in 7 subgroups of each material (n=8). Sixteen untreated samples served as controls. Dimensional change was measured with a digital micrometer in the reference lines on the sample. Results: The highest mean percentage of dimensional change for the 50 min autoclave was 0.10±0.03% for CS and 0.10±0.02% for VPS. The dimensional change in CS did not differ for hydrogen peroxide. Compared with the controls, dimensional change was significant in 20 min NaOCl and 50 min autoclave (p<.05). Both impression materials in the autoclave showed statistically significant dimensional changes regardless of the time. The difference in application duration significantly affected the dimensional stability of the impression materials regardless of the procedure (p<.001). Extended application duration did not affect the dimensional stability in the hydrogen peroxide for CS, NaOCl and autoclave for VPS. Conclusions: Chemical disinfection and autoclave sterilization caused statistically significant but clinically acceptable dimensional changes in CS and VPS impression materials used in this study.

[YODADA Y PEROXIDO DE HIDROGENO EN PACIENTES CON COVID-19]. / UTILIDAD DE LOS ENJUAGUES CON POVIDONA.

INTRODUCTION: Povidone-iodine and hydrogen peroxide could be effective in against SARS-CoV-2. METHODS: A "non-interventional trial" in 88 patients (43±17 yrs., 55% men) with SARS-CoV-2 in nasopharyngeal swabs (RT-PCR). 31 received mouth rinses/gargling with povidone-iodine (every 8 hours, two consecutive days), 17 with mouth rinses/gargling of hydrogen peroxide, and 40 controls. Were repeated PCR in 3, 11 and 17 days. RESULTS: After intervention the viral load (Log10 copies/ml) remained similar in povidone-iodine (4.3±2.7 copies/ml), hydrogen peroxide (4.6±2.9 copies/ml; p=0.40) and controls (4.4±3.0 copies/ml). The percentage of patients with a negative result in the second PCR was 27% in povidone-iodine group, 23% in hydrogen peroxide and 32% in controls; in the third PCR, 62%, 54% y 58% respectively; and in the fourth PCR, 81%, 75% y 81%. CONCLUSION: Our results do not support the clinical usefulness of mouth rinses/gargling with povidone-iodine or hydrogen peroxide in patients with COVID-19.

The dental office: A safe place against COVID19 and other future pandemics

Background: The pandemic caused by the spread of COVID19 generated throughout the world great changes in all areas of life. Social distancing was carried out very drastically in some countries, and even in the field of dental care, some countries prohibited the practice of dentistry. Objective(s): To demonstrate that the dental office is safe regarding the possibility of contagion of Sars-Cov-2 as long as good biosecurity protocols are used. Method(s): A structured survey of 19 questions was applied to 103 patients who subsequently attended a periodontics and oral and maxillofacial surgery office in Mexico, to receive care from these specialties between April 2020 and July 2021. The questions posed in this survey were aimed at knowing the opinion of the patients regarding the measures that this establishment has for the prevention of the transmission of COVID19, as well as questions regarding the possible effects of attending this office in contagion of the disease from patients and their families. Result(s): A total of 18 (17.5%) patients reported having suffered COVID19, and none reported that they fell ill after the consultation. None of the clinic's specialists and assistants have fallen ill with COVID-19 during the pandemic. Conclusion(s): It is not necessary to suspend or condition dental care during times of pandemics such as what happened with COVID19, as long as strict safety protocols are observed within clinical facilities.Copyright © 2022 The Authors

The effects of acute hydrogen peroxide exposure on respiratory cilia motility and viability.

COVID-19 has seen the propagation of alternative remedies to treat respiratory disease, such as nebulization of hydrogen peroxide (H2O2). As H2O2 has known cytotoxicity, it was hypothesised that H2O2 inhalation would negatively impact respiratory cilia function. To test this hypothesis, mouse tracheal samples were incubated with different H2O2 concentrations (0.1-1%) then cilia motility, cilia generated flow, and cell death was assessed 0-120 min following H2O2 treatment. 0.1-0.2% H2O2 caused immediate depression of cilia motility and complete cessation of cilia generated flow. Higher H2O2 concentrations (≥0.5%) caused immediate complete cessation of cilia motility and cilia generated flow. Cilia motility and flow was restored 30 min after 0.1% H2O2 treatment. Cilia motility and flow remained depressed 120 min after 0.2-0.5% H2O2 treatment. No recovery was seen 120 min after treatment with ≥1% H2O2. Live/dead staining revealed that H2O2 treatment caused preferential cell death of ciliated respiratory epithelia over non-ciliated epithelia, with 1% H2O2 causing 35.3 ± 7.0% of the ciliated epithelia cells to die 120 min following initial treatment. This study shows that H2O2 treatment significantly impacts respiratory cilia motility and cilia generated flow, characterised by a significant impairment in cilia motility even at low concentrations, the complete cessation of cilia motility at higher doses, and a significant cytotoxic effect on ciliated respiratory epithelial cells by promoting cell death. While this data needs further study using in vivo models, it suggests that extreme care should be taken when considering treating respiratory diseases with nebulised H2O2.

Oxidative stress induces MUC5AC expression through mitochondrial damage-dependent STING signaling in human bronchial epithelial cells.

Oxidative stress increases the production of the predominant mucin MUC5AC in airway epithelial cells and is implicated in the pathogenesis of bronchial asthma and chronic obstructive pulmonary disease. Oxidative stress impairs mitochondria, releasing mitochondrial DNA into the cytoplasm and inducing inflammation through the intracytoplasmic DNA sensor STING (stimulator of interferon genes). However, the role of innate immunity in mucin production remains unknown. We aimed to elucidate the role of innate immunity in mucin production in airway epithelial cells under oxidative stress. Human airway epithelial cell line (NCI-H292) and normal human bronchial epithelial cells were used to confirm MUC5AC expression levels by real-time PCR when stimulated with hydrogen peroxide (H2O2). MUC5AC transcriptional activity was increased and mitochondrial DNA was released into the cytosol by H2O2. Mitochondrial antioxidants were used to confirm the effects of mitochondrial oxidative stress where antioxidants inhibited the increase in MUC5AC transcriptional activity. Cyclic GMP-AMP synthase (cGAS) or STING knockout (KO) cells were generated to investigate their involvement. H2O2-induced MUC5AC expression was suppressed in STING KO cells, but not in cGAS KO cells. The epidermal growth factor receptor was comparably expressed in STING KO and wild-type cells. Thus, mitochondria and STING play important roles in mucin production in response to oxidative stress in airway epithelial cells.

Utility of mouth rinses with povidone-iodine and hydrogen peroxide in patients with COVID-19.

INTRODUCTION: Povidone-iodine and hydrogen peroxide could be effective in against SARS-CoV-2. METHODS: A "non-interventional trial" in 88 patients (43±17 yrs., 55% men) with SARS-CoV-2 in nasopharyngeal swabs (RT-PCR). 31 received mouth rinses/gargling with povidone-iodine (every 8h, two consecutive days), 17 with mouth rinses/gargling of hydrogen peroxide, and 40 controls. Were repeated PCR in 3, 11 and 17 days. RESULTS: After intervention the viral load (Log10 copies/ml) remained similar in povidone-iodine (4.3±2.7 copies/ml), hydrogen peroxide (4.6±2.9 copies/ml; p=0.40) and controls (4.4±3.0 copies/ml). The percentage of patients with a negative result in the second PCR was 27% in povidone-iodine group, 23% in hydrogen peroxide and 32% in controls; in the third PCR, 62%, 54% y 58% respectively; and in the fourth PCR, 81%, 75% y 81%. CONCLUSION: Our results do not support the clinical usefulness of mouth rinses/gargling with povidone-iodine or hydrogen peroxide in patients with COVID-19.

Timing of embolic phenomena after hydrogen peroxide exposure - a systematic review.

INTRODUCTION: Hydrogen peroxide ingestions cause significant morbidity and mortality due to oxygen gas emboli and are treatable with hyperbaric oxygen therapy. Recommendations for observation are based on small case series. OBJECTIVES: The aim of this systematic review is to define the time of onset of embolic phenomena after hydrogen peroxide exposure and to describe the proportion of patients who received hyperbaric oxygen therapy. METHODS: Cases from a systematic literature search were combined with those from a prior study that used data derived from the American Association of Poison Control Centers National Poison Data System. Air-gas emboli were defined as embolic phenomena (stroke, myocardial infarction, obstructive shock) potentially reversed with hyperbaric oxygen therapy. Simple counts, mean, and interquartile range were used for description and comparisons. RESULTS: A total of 766 records were identified in the literature search. Three-hundred and eighty-three duplicate records were identified and removed. Of the 383 remaining records, 156 met inclusion criteria; 88 were excluded based on predetermined criteria yielding 68 records with 85 unique cases. Forty-one cases were extracted from the 2017 National Poison Data System study resulting in a total of 126 cases for analysis. Case descriptions: We analyzed these 126 cases and documented 213 discrete clinical events, excluding deaths. There were 108 high-concentration exposures, 10 low-concentration exposures, and 8 were unknown. Thirty-five cases were intentional ingestions but not for self-harm, and 84 were unintentional or accidental. Only 4 cases were for self-harm, and there were 23 pediatric cases. There were 99 air-gas emboli reported in 78 patients. Time to onset: The time to onset of air-gas embolic was documented in 70/78. Time to symptom onset ranged from immediate to 72 h after hydrogen peroxide exposure. Over 90% of embolic symptoms occurred within 10 h of ingestion. Hyperbaric oxygen therapy: A total of 54/126 cases received hyperbaric oxygen therapy. Of those 54 cases, 31 had primary portal venous gas while the remaining 23 had air-gas emboli. Of the 23 air-gas emboli cases treated with hyperbaric oxygen therapy, 13 made full recoveries while 10 had residual symptoms or died. Mean time from air-gas emboli symptom onset to hyperbaric oxygen therapy in the full recovery group was 9 h compared to 18.2 h in the partial recovery/death group. Portal venous gas: There were 63 total reported cases of portal venous gas. Forty-nine of these cases were primary portal venous gas, 13 were secondary findings in patients with air-gas emboli and one case was secondary to non-air-gas emboli symptoms. Twenty-seven of 49 patients with portal venous gas (55%) as the primary finding had gastrointestinal bleeding. Thirty of the 63 cases received hyperbaric oxygen therapy for portal venous gas without any documented air-gas emboli. Deaths: Seventeen deaths occurred in the combined cohort. Of these, 13 were associated with high-concentration exposures. All deaths with reported time to symptom onset had symptoms within 1 h of exposure. CONCLUSION: This review of hydrogen peroxide exposure cases suggests that clinically significant embolic phenomena occur within 10 h of exposure, although delayed air-gas emboli do happen and should considered when deciding duration of observation. It remains equivocal whether hyperbaric oxygen therapy is beneficial in cases of primary portal venous gas without systemic involvement.

Filtration performance of three models of N95 filtering facepiece respirators following clinical usage and vaporized hydrogen peroxide decontamination.

BACKGROUND: N95 filtering facepiece respirators (FFRs) are essential personal protective equipment (PPE) for protecting healthcare workers from airborne pathogens. AIM: To perform the first large-scale evaluation of particulate filtration efficiency (PFE) of three models of N95 FFRs following clinical usage and vaporized hydrogen peroxide (VHP) decontamination. METHODS: Three variables were assessed for effect on PFE following VHP decontamination: VHP sterilizer model, N95 respirator model, and prior N95 clinical usage. FINDINGS: The VHP sterilizer model and N95 FFR model impacted PFE performance. Worn N95 FFRs had a 91% lower odds of exhibiting ≥95% PFE compared with the control. CONCLUSION: This work highlights the importance of validating any N95 FFR decontamination programme in its entirety, including prior clinical usage.

Fuelling the Immune System for the 21st Century

The article presents a reprint of the article Fuelling the Immune System for the 21st Century by Michael Passwater which appeared in the February 2023 issue of immune function. Topics discussed include global occurrences of emerging and re-emerging infectious diseases, the importance of nutrition in supporting the immune system, the value of the vitamins C and D, and the status of proton pump inhibitors (PPI). Also noted are suggested adult doses of nutrients.