Place of high-flow nasal oxygen in nonoperating room anesthesia.

PURPOSE OF REVIEW: This article aims to assess the utility of high-flow nasal oxygen (HFNO) therapy in nonoperating room anesthesia (NORA) settings. RECENT FINDINGS: The number of procedural interventions under deep sedation in NORA is still increasing. Administration of oxygen is recommended to prevent hypoxemia and is usually delivered with standard oxygen through nasal cannula or a face mask. HFNO is a simple alternative with a high warmed humidified flow (ranging from 30 to 70 l/min) with a precise fraction inspired of oxygen (ranging from 21 to 100%). Compared to standard oxygen, HFNO has demonstrated efficacy in reducing the incidence of hypoxemia and the need for airway maneuvers. Research on HFNO has primarily focused on its application in gastrointestinal endoscopy procedures. Yet, it has also shown promising results in various other procedural interventions including bronchoscopy, cardiology, and endovascular procedures. However, the adoption of HFNO prompted considerations regarding cost-effectiveness and environmental impact. SUMMARY: HFNO emerges as a compelling alternative to conventional oxygen delivery methods for preventing hypoxemia during procedural interventions in NORA. However, its utilization should be reserved for patients at moderate-to-high risk to mitigate the impact of cost and environmental factors.

Cost-effectiveness and sustainability of improved hospital oxygen systems in Nigeria.

INTRODUCTION: Improving hospital oxygen systems can improve quality of care and reduce mortality for children, but we lack data on cost-effectiveness or sustainability. This study evaluated medium-term sustainability and cost-effectiveness of the Nigeria Oxygen Implementation programme. METHODS: Prospective follow-up of a stepped-wedge trial involving 12 secondary-level hospitals. Cross-sectional facility assessment, clinical audit (January-March 2021), summary admission data (January 2018-December 2020), programme cost data. INTERVENTION: pulse oximetry introduction followed by solar-powered oxygen system installation with clinical and technical training and support. PRIMARY OUTCOMES: (i) proportion of children screened with pulse oximetry; (ii) proportion of hypoxaemic (SpO2 <90%) children who received oxygen. Comparison across three time periods: preintervention (2014-2015), intervention (2016-2017) and follow-up (2018-2020) using mixed-effects logistic regression. Calculated cost-effectiveness of the intervention on child pneumonia mortality using programme costs, recorded deaths and estimated counterfactual deaths using effectiveness estimates from our effectiveness study. Reported cost-effectiveness over the original 2-year intervention period (2016-2017) and extrapolated over 5 years (2016-2020). RESULTS: Pulse oximetry coverage for neonates and children remained high during follow-up (83% and 81%) compared with full oxygen system period (94% and 92%) and preintervention (3.9% and 2.9%). Oxygen coverage for hypoxaemic neonates/children was similarly high (94%/88%) compared with full oxygen system period (90%/82%). Functional oxygen sources were present in 11/12 (92%) paediatric areas and all (8/8) neonatal areas; three-quarters (15/20) of wards had a functional oximeter. Of 32 concentrators deployed, 23/32 (72%) passed technical testing and usage was high (median 10 797 hours). Estimated 5-year cost-effectiveness US$86 per patient treated, $2694-4382 per life saved and $82-125 per disability-adjusted life year-averted. We identified practical issues for hospitals and Ministries of Health wishing to adapt and scale up pulse oximetry and oxygen. CONCLUSION: Hospital-level improvements to oxygen and pulse oximetry systems in Nigerian hospitals have been sustained over the medium-term and are a highly cost-effective child pneumonia intervention.

Treatment of moderate to severe respiratory COVID-19: a cost-utility analysis.

Despite COVID-19's significant morbidity and mortality, considering cost-effectiveness of pharmacologic treatment strategies for hospitalized patients remains critical to support healthcare resource decisions within budgetary constraints. As such, we calculated the cost-effectiveness of using remdesivir and dexamethasone for moderate to severe COVID-19 respiratory infections using the United States health care system as a representative model. A decision analytic model modelled a base case scenario of a 60-year-old patient admitted to hospital with COVID-19. Patients requiring oxygen were considered moderate severity, and patients with severe COVID-19 required intubation with intensive care. Strategies modelled included giving remdesivir to all patients, remdesivir in only moderate and only severe infections, dexamethasone to all patients, dexamethasone in severe infections, remdesivir in moderate/dexamethasone in severe infections, and best supportive care. Data for the model came from the published literature. The time horizon was 1 year; no discounting was performed due to the short duration. The perspective was of the payer in the United States health care system. Supportive care for moderate/severe COVID-19 cost $11,112.98 with 0.7155 quality adjusted life-year (QALY) obtained. Using dexamethasone for all patients was the most-cost effective with an incremental cost-effectiveness ratio of $980.84/QALY; all remdesivir strategies were more costly and less effective. Probabilistic sensitivity analyses showed dexamethasone for all patients was most cost-effective in 98.3% of scenarios. Dexamethasone for moderate-severe COVID-19 infections was the most cost-effective strategy and would have minimal budget impact. Based on current data, remdesivir is unlikely to be a cost-effective treatment for COVID-19.

Estimated Cost-effectiveness of Solar-Powered Oxygen Delivery for Pneumonia in Young Children in Low-Resource Settings.

Importance: Pneumonia is the leading cause of childhood mortality worldwide. Severe pneumonia associated with hypoxemia requires oxygen therapy; however, access remains unreliable in low- and middle-income countries. Solar-powered oxygen delivery (solar-powered O2) has been shown to be a safe and effective technology for delivering medical oxygen. Examining the cost-effectiveness of this innovation is critical for guiding implementation in low-resource settings. Objective: To determine the cost-effectiveness of solar-powered O2 for treating children in low-resource settings with severe pneumonia who require oxygen therapy. Design, Setting, and Participants: An economic evaluation study of solar-powered O2 was conducted from January 12, 2020, to February 27, 2021, in compliance with the World Health Organization Choosing Interventions That Are Cost-Effective (WHO-CHOICE) guidelines. Using existing literature, plausible ranges for component costs of solar-powered O2 were determined in order to calculate the expected total cost of implementation. The costs of implementing solar-powered O2 at a single health facility in low- and middle-income countries was analyzed for pediatric patients younger than 5 years who required supplemental oxygen. Exposures: Treatment with solar-powered O2. Main Outcomes and Measures: The incremental cost-effectiveness ratio (ICER) of solar-powered O2 was calculated as the additional cost per disability-adjusted life-year (DALY) saved. Sensitivity of the ICER to uncertainties of input parameters was assessed through univariate and probabilistic sensitivity analyses. Results: The ICER of solar-powered O2 was estimated to be $20 (US dollars) per DALY saved (95% CI, $2.83-$206) relative to the null case (no oxygen). Costs of solar-powered O2 were alternatively quantified as $26 per patient treated and $542 per life saved. Univariate sensitivity analysis found that the ICER was most sensitive to the volume of pediatric pneumonia admissions and the case fatality rate. The ICER was insensitive to component costs of solar-powered O2 systems. In secondary analyses, solar-powered O2 was cost-effective relative to grid-powered concentrators (ICER $140 per DALY saved) and cost-saving relative to fuel generator-powered concentrators (cost saving of $7120). Conclusions and Relevance: The results of this economic evaluation suggest that solar-powered O2 is a cost-effective solution for treating hypoxemia in young children in low- and middle-income countries, relative to no oxygen. Future implementation should prioritize sites with high rates of pediatric pneumonia admissions and mortality. This study provides economic support for expansion of solar-powered O2 and further assessment of its efficacy and mortality benefit.

Insights into real-world treatment of cluster headache through a large Italian database: prevalence, prescription patterns, and costs.

Objective: This study aimed at estimating the treated cluster headache (CH) prevalence and describing prescription patterns and direct costs paid by the Italian National-Health-System.Methods: Through the ReS database (healthcare administrative data collection of a large sample of the Italian population), adults in treatment for CH (acute therapy with sumatriptan/subcutaneous or oxygen, associated with preventive therapy with verapamil or lithium) were selected. A cross-sectional analysis described the prevalence of CH-treated subjects repeated annually in 2013-2017. A longitudinal analysis of patients selected in 2013-2015 and followed for 2 years provided the prescription patterns.Results: The annual prevalence of CH-treated patients increased from 6.4×100,000 adults in 2013 to 6.7 in 2017. In 2013-2015, 570 patients (80.7% M; mean age 46) treated for CH were found. In 50.4%, the identifying CH treatment was sumatriptan/subcutaneous+verapamil. During follow-up, >1/3 changed the preventive drug and interruption was the most frequent modification, although acute treatments were still prescribed. The mean annual cost/patient ranged from €2,956 to €2,267; pharmaceuticals expenditure represented the 56.4% and 57.3%, respectively.Conclusions: This study showed an important unmet need among CH patients, carrying a high economic burden that should be considered in the evaluation of the impact of incoming therapies (e.g. Calcitonin-Gene-Related-Peptide antibodies).

Evaluación rápida de efectividad y seguridad del uso de cánula de alto flujo de oxígeno en COVID-19 para reducir la mortalidad o requerimiento de ventilación mecánica / Rapid evaluation of the effectiveness and safety of the use of high-flow oxygen cannula in COVID-19 to reduce mortality or the need for mechanical ventilation

INTRODUCCIÓN: La Enfermedad por Coronavirus 2019 (Covid-19) se registró por primera vez en diciembre de 2019 en Wuhan, provincia de Hubei, China. El desarrollo de una enfermedad respiratoria altamente transmisible y de curso variable e impredecible orientó los esfuerzos hacia la identificación del agente y el estudio de los casos que permitieran el desarrollo de medidas adecuadas para contener su dispersión y dar mejor respuesta. Se demostró que la causa de estas afecciones era un nuevo coronavirus estructuralmente relacionado con el virus que causa el síndrome respiratorio agudo severo (SARS), que años atrás ya había causado otras infecciones por coronavirus (SARS en 2002 y 2003, y síndrome respiratorio del Medio Oriente -MERS en 2012) en el mundo. El 30 de enero de 2020, tras las crecientes tasas de notificación de casos en diversas localizaciones en China y la identificación de casos en otros 18 países, la organización Mundial de la Salud OMS declaró que el brote por el nuevo coronavirus (2019-nCov) constituye una emergencia de salud pública de importancia internacional (ESPII). El seguimiento a la epidemia, aún con las limitaciones para disponer de información en tiempo real, ha permitido conocer la evolución de la misma en el mundo. De acuerdo con los más recientes informes, más de 70 millones de personas han sido confirmadas con COVID-19 en cerca de 191 países, y en las Américas la cifra está en ascenso. La epidemia de COVID-19 se inició en Colombia el 6 de marzo 2020, actualmente el número de casos diarios reportados supera los 11.00 y a diciembre 20 se ha registrado un total de 1'507.222 casos confirmados de los cuales 89.330 están activos. Las tasas de letalidad reportadas son muy variables entre países y aún entre regiones de cada país, dado principalmente por las características y condiciones poblacionales y el acceso a servicios de salud. Se estima que actualmente la letalidad es cerca del 4% o incluso menor, considerando que el número de casos asintomáticos o mínimamente sintomáticos es varias veces mayor que el número de casos notificados. OBJETIVO: Sintetizar la evidencia disponible para establecer la efectividad y seguridad del uso de cánula de alto flujo de oxígeno en adultos con COVID-19 que requieran manejo hospitalario, a fin de orientar la toma de decisiones en el marco de la pandemia por coronavirus en Colombia. METODOLOGÍA: Población: Estudios que incluyan únicamente adultos con diagnóstico de neumonía por COVID-19, que requieren manejo hospitalario con suplencia de oxígeno. Tecnología de interés: Estudios que comparen cánula nasal de alto flujo de oxígeno vs. ventilación mecánica no invasiva (mascarilla con reservorio de reinhalación parcial, de no reinhalación y Venturi) Desenlaces: Estudios que incluyan información sobre requerimiento de ventilación mecánica invasiva, mortalidad, eventos adversos o aspersión de partículas virales. Tiempo: El tiempo de medición de los desenlaces se reportó de acuerdo con lo informado en los estudios. Se llevó a cabo una búsqueda sistemática de literatura. Todo el proceso se acogió a los estándares de calidad internacional utilizados por la Colaboración Cochrane para Revisiones Rápidas. RESULTADOS: Las estrategias de búsqueda, así como las bases de datos consultadas, se presentan en el Anexo 2. Fueron identificadas 103 referencias después de remover duplicados, de los cuales fueron incluidos para revisión en texto completo 16 artículos y fueron incluidos 4 de ellos. De forma adicional se realizó una búsqueda en la página de clinicaltrials.gov los resultados se presentan en la Tabla 4 así como las características de los estudios, la búsqueda en el portal WHO International Clinical Trials Registry Platform ­ ICTRP no fue posible consultarla. La búsqueda complementaria en los motores de búsqueda Google y en Google Académico no retribuyó estudios adicionales a los encontrados en las bases de datos indexadas. CONCLUSIONES: La información aquí presentada sugiere que en pacientes con insuficiencia respiratoria hipoxémica secundaria a neumonía por SARS-CoV2 (COVID-19) y con mayores necesidades de las que pueden proveer los dispositivos de bajo flujo, la decisión de proveer oxigenoterapia con cánula nasal de alto flujo (CNAF) y ventilación no invasiva (VNI) requiere de un balance entre los riesgos y beneficios para el paciente, así como el riesgo de exposición para los trabajadores de la salud, además de la consideración de optimizar los recursos disponibles. La información proveniente de los estudios incluidos en esta revisión sugiere que las medidas no invasivas como la CNAF, parecen seguras y podrían traer beneficios al paciente que lo requiera, antes de proceder a la intubación endotraqueal temprana. Se hace necesario a futuro, el análisis de información de estudios experimentales bien diseñados para poder establecer con certeza la efectividad de las tecnologías analizadas en la presente revisión.

Solar-powered oxygen, quality improvement and child pneumonia deaths: a large-scale effectiveness study.

BACKGROUND: Pneumonia is the largest cause of child deaths in low-income countries. Lack of availability of oxygen in small rural hospitals results in avoidable deaths and unnecessary and unsafe referrals. METHOD: We evaluated a programme for improving reliable oxygen therapy using oxygen concentrators, pulse oximeters and sustainable solar power in 38 remote health facilities in nine provinces in Papua New Guinea. The programme included a quality improvement approach with training, identification of gaps, problem solving and corrective measures. Admissions and deaths from pneumonia and overall paediatric admissions, deaths and referrals were recorded using routine health information data for 2-4 years prior to the intervention and 2-4 years after. Using Poisson regression we calculated incidence rates (IRs) preintervention and postintervention, and incidence rate ratios (IRR). RESULTS: There were 18 933 pneumonia admissions and 530 pneumonia deaths. Pneumonia admission numbers were significantly lower in the postintervention era than in the preintervention era. The IRs for pneumonia deaths preintervention and postintervention were 2.83 (1.98-4.06) and 1.17 (0.48-1.86) per 100 pneumonia admissions: the IRR for pneumonia deaths was 0.41 (0.24-0.71, p<0.005). There were 58 324 paediatric admissions and 2259 paediatric deaths. The IR for child deaths preintervention and postintervention were 3.22 (2.42-4.28) and 1.94 (1.23-2.65) per 100 paediatric admissions: IRR 0.60 (0.45-0.81, p<0.005). In the years postintervention period, an estimated 348 lives were saved, at a cost of US$6435 per life saved and over 1500 referrals were avoided. CONCLUSIONS: Solar-powered oxygen systems supported by continuous quality improvement can be achieved at large scale in rural and remote hospitals and health care facilities, and was associated with reduced child deaths and reduced referrals. Variability of effectiveness in different contexts calls for strengthening of quality improvement in rural health facilities. TRIAL REGISTRATION NUMBER: ACTRN12616001469404.

The role of CPAP as a potential bridge to invasive ventilation and as a ceiling-of-care for patients hospitalized with Covid-19-An observational study.

BACKGROUND: Continuous positive airway pressure (CPAP) ventilation may be used as a potential bridge to invasive mechanical ventilation (IMV), or as a ceiling-of-care for persistent hypoxaemia despite standard oxygen therapy, according to UK guidelines. We examined the association of mode of respiratory support and ceiling-of-care on mortality. METHODS: We conducted a retrospective cohort analysis of routinely collected de-identified data of adults with nasal/throat SARs-CoV-2 swab-positive results, at the Calderdale and Huddersfield NHS Foundation Trust between 10th March-19th April 2020 (outcomes determined on 22nd May). FINDINGS: Of 347 patients with SARs-CoV-2 swab-positive results, 294 (84.7%) patients admitted for Covid-19 were included in the study. Sixty-nine patients were trialled on CPAP, mostly delivered by face mask, either as an early ceiling of care instituted within 24 hours of admission (N = 19), or as a potential bridge to IMV (N = 44). Patients receiving a ceiling of care more than 24 hours after admission (N = 6) were excluded from the analysis. Two hundred and fifteen patients (73.1%) maximally received air/standard oxygen therapy, and 45 (15.3%) patients maximally received CPAP. Thirty-four patients (11.6%) required IMV, of which 24 had received prior CPAP. There were 138 patients with an early ceiling-of-care plan (pre-admission/within 24h). Overall, 103(35.0%) patients died and 191(65.0%) were alive at study end. Among all patients trialled on CPAP either as a potential bridge to IMV (N = 44) or as a ceiling-of-care (N = 19) mortality was 25% and 84%, respectively. Overall, there was strong evidence for higher mortality among patients who required CPAP or IMV, compared to those who required only air/oxygen (aOR 5.24 95%CI: 1.38, 19.81 and aOR 46.47 95%CI: 7.52, 287.08, respectively; p<0.001), and among patients with early ceiling-of-care compared to those without a ceiling (aOR 41.81 95%CI: 8.28, 211.17; p<0.001). Among patients without a ceiling of care (N = 137), 10 patients required prompt intubation following failed oxygen therapy, but 44 patients received CPAP. CPAP failure, defined as death (N = 1) or intubation (N = 24), occurred in 57% (N = 25) of patients. But in total, 75% (N = 33) of those started on CPAP with no ceiling of care recovered to discharge-19 without the need for IMV, and 14 following IMV. CONCLUSION: Our data suggest that among patients with no ceiling-of-care, an initial trial of CPAP as a potential bridge to IMV offers a favourable therapeutic alternative to early intubation. In contrast, among patients with a ceiling-of care, CPAP seems to offer little additional survival benefit beyond oxygen therapy alone. Information on ceilings of respiratory support is vital to interpreting mortality from Covid-19. STRENGTHS AND LIMITATIONS OF THIS STUDY: Sample size relatively small.Study sample representative of hospitalised Covid-19 patients in UK.Previously unreported data on role of ceilings-of-care in hospitalised Covid-19 patients.Novel data on use of CPAP separated by indication.

Protocol of a multicentre, prospective cohort study that evaluates cost-effectiveness of two perioperative care strategies for potential obstructive sleep apnoea in morbidly obese patients undergoing bariatric surgery.

INTRODUCTION: Despite the high prevalence of obstructive sleep apnoea (OSA) in obese patients undergoing bariatric surgery, OSA is undiagnosed in the majority of patients and thus untreated. While untreated OSA is associated with an increased risk of preoperative and postoperative complications, no evidence-based guidelines on perioperative care for these patients are available. The aim of the POPCORN study (Post-Operative Pulse oximetry without OSA sCreening vs perioperative continuous positive airway pressure (CPAP) treatment following OSA scReeNing by polygraphy (PG)) is to evaluate which perioperative strategy is the most cost-effective for obese patients undergoing bariatric surgery without a history of OSA. METHODS AND ANALYSIS: In this multicentre observational cohort study, data from 1380 patients who will undergo bariatric surgery will be collected. Patients will receive either postoperative care with pulse oximetry monitoring and supplemental oxygen during the first postoperative night, or care that includes preoperative PG and CPAP treatment in case of moderate or severe OSA. Local protocols for perioperative care in each participating hospital will determine into which cohort a patient is placed. The primary outcome is cost-effectiveness, which will be calculated by comparing all healthcare costs with the quality-adjusted life-years (QALYs, calculated using EQ-5D questionnaires). Secondary outcomes are mortality, complications within 30 days after surgery, readmissions, reoperations, length of stay, weight loss, generic quality of life (QOL), OSA-specific QOL, OSA symptoms and CPAP adherence. Patients will receive questionnaires before surgery and 1, 3, 6 and 12 months after surgery to report QALYs and other patient-reported outcomes. ETHICS AND DISSEMINATION: Approval from the Medical Research Ethics Committees United was granted in accordance with the Dutch law for Medical Research Involving Human Subjects Act (WMO) (reference number W17.050). Results will be submitted for publication in peer-reviewed journals and presented at (inter)national conferences. TRIAL REGISTRATION NUMBER: NTR6991.

An Oxygen Delivery Polymer Enhances Seed Germination in a Martian-like Environment.

Critical to the success of establishing a sustainable human presence on Mars is the ability to economically grow crop plants. Several environmental factors make it difficult to fully rely on local resources for agriculture. These include nutrient sparse regolith, low and fluctuating temperatures, a high amount of ultraviolet radiation, and water trapped locally in the form of ice or metal oxides. While the 96% CO2 martian atmosphere is ideal to support photosynthesis, high CO2 concentrations inhibit germination. An added difficulty is the fact that a vast majority of crop plants require oxygen for germination. Here, we report the production of a polymer-based oxygen delivery system that supports the germination and growth of cress seeds (Lepidium sativum) in a martian regolith simulant under a martian atmosphere at 101 kPa. The oxygen-donating system is based on a low-density lightly cross-linked polyacrylate that is foamed and converted into a dry powder. It is lightweight, added in low amounts to regolith simulant, and efficiently donates enough oxygen throughout the volume of hydrated regolith simulant to fully support seed germination and plant growth. Germination rates, plant development, and plant mass are nearly identical for L. sativum grown in 100% CO2 in the presence of the oxygen-donating lightly cross-linked polyacrylate compared with plants grown in air. The polymer system also serves to protect root structures and better anchors plants in the regolith simulant.

Providing oxygen to children and newborns: a multi-faceted technical and clinical assessment of oxygen access and oxygen use in secondary-level hospitals in southwest Nigeria.

BACKGROUND: Oxygen is an essential medical therapy that is poorly available globally. We evaluated the quality of oxygen therapy in 12 secondary-level Nigerian hospitals, including access to oxygen equipment, equipment functionality, healthcare worker knowledge and appropriateness of use. METHODS: We conducted a three-part evaluation of oxygen access and use involving: (1) facility assessment (including technical evaluation of oxygen equipment), (2) clinical audit (children and neonates admitted January 2014-December 2015) and (3) survey of healthcare worker training and experience on the clinical use of oxygen (November 2015). RESULTS: Oxygen access for children and newborns is compromised by faulty equipment, lack of pulse oximetry and inadequate care practices. One hospital used pulse oximetry for paediatric care. Eleven hospitals had some access to oxygen supplies. Testing of 57 oxygen concentrators revealed two (3.5%) that were 'fit for use'. Overall, 14.4% (3708/25 677) of children and neonates received oxygen some time during their admission; 19.4% (1944/10 000) of hypoxaemic children received oxygen; 38.5% (1217/3161) of children who received oxygen therapy were not hypoxaemic. CONCLUSIONS: Oxygen access for children in Nigerian hospitals is poor, and likely results in substantial excess mortality. To improve oxygen access for children globally we must focus on actual provision of oxygen to patients-not simply the presence of oxygen equipment at the facility level. This requires a systematic approach to improve both oxygen (access [including equipment, maintenance and affordability]) and oxygen use (including pulse oximetry, guidelines and continuing education).

Exploratory Assessment of Oxygen Flow-Assisted Cutaneous Administration of Methotrexate for Superficial Basal Cell Carcinoma, Mycosis Fungoides, and Extramammary Paget Disease.

The molecular weight of methotrexate (MTX) makes cutaneous penetration difficult. Oxygen flow could enhance the skin permeation of MTX diluted in the proprietary LP3 carrier system. This pilot study aims to assess the efficacy, safety, and tolerance of oxygen flow-assisted LP3-MTX3% for treating superficial skin cancers. Patients with superficial basal cell carcinoma (n = 12), extramammary Paget disease (n = 5), classic mycosis fungoides (MF; n = 10), and folliculotropic MF (n = 6) were included in the study and were treated with four weekly applications of oxygen flow-assisted LP3-MTX3%. Photographs and biopsies were performed before and one month after treatment. At one month after treatment, the mean superficial basal cell carcinoma erythema-crusting-thickness clinical score, the extramammary Paget disease erythema-oozing-scaling/hyperkeratosis-pain/pruritus clinical score, and the modified composite assessment of index lesion severity classic MF and folliculotropic MF scores were improved by 77.5% ± 17.1% (P < 0.0001), 66.7% ± 22.9% (P = 0.011), 51.3% ± 32.2% (P = 0.0007), and 27.8% ± 32.0% (P = 0.086), respectively. At one month after treatment, histology revealed partial and total clearances for superficial basal cell carcinoma (1/12, 11/12), extramammary Paget disease (4/5, 1/5), classic MF (8/10, 2/10), and folliculotropic MF (6/6, 0/6). Tolerance was excellent and no pain was observed. MTX was never detectable in serum at baseline and 1, 2, 3, 8, 24, 48, and 72 hours post-treatment. In conclusion, the interesting therapeutic efficacy of oxygen flow-assisted LP3-MTX3% for treating superficial basal cell carcinoma, extramammary Paget disease, and MF lesions prompts further studies on a larger scale.

Carbogen gas-challenge BOLD fMRI in assessment of liver hypoxia after portal microcapsules implantation.

BACKGROUND: Hypoxia is one of the key factors affecting the survival of islet cells transplanted via the portal vein. Blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) is the only imaging technique that can detect the level of blood oxygen level in vivo. However, so far no study has indicated that BOLD-fMRI can be applied to monitor the liver oxygen level after islet transplantation. OBJECTIVE: To evaluate the value of Carbogen-challenge BOLD MRI in assessing the level of hypoxia in liver tissue after portal microcapsules implanted. METHODS: Fifty-one New Zealand rabbits were randomly divided into three experimental groups (15 in each group) were transplanted microencapsulated 1000 microbeads/kg (PV1 group), 3000 microbeads/kg (PV2 group), 5000 microbeads/kg (PV3 group), and 6 rabbits were injected with the same amount of saline as the control group, BOLD-fMRI was performed following carbogen breathing in each group after transplantation on 1d, 2d, 3d and 7d, T2* weighted image, R2* value and ΔR2* value parameters for the liver tissue. Pathological examinations including liver gross pathology, H&E staining and pimonidazole immunohistochemistry were performed after BOLD-fMRI. The differences of pathological results among each group were compared. The ΔR2* values and transplanted doses were analyzed. RESULTS AND CONCLUSIONS: ΔR2* values at the 1-3d and 7d after transplantation were significantly different in each groups (P<0.05). ΔR2* values decreased gradually with the increase of transplanted dose, and was negatively correlated with transplant dose at 3d after transplantation (r = -0.929, P <0.001). Liver histopathological examination showed that the degree of hypoxia of liver tissue increased with the increase of transplanted doses, Carbogen-challenge BOLD-fMRI can assess the degree of liver hypoxia after portal microcapsules implanted, which provided a monitoring method for early intervention.

Assessment of sensory sensitivity through critical flicker fusion frequency thresholds after a maximum voluntary apnoea.

INTRODUCTION: The influence of acute exercise on sensory sensitivity (SS) differs according to the type and duration of exercise performed. In the present study, we assessed changes on SS soon after a maximal dynamic apnoea. METHODS: Thirty-nine experienced male breath-hold divers were recruited. Critical flicker fusion frequency (CFFF) thresholds were used to measure SS. Thresholds were determined before and after a maximal dynamic apnoea. Immediately after surfacing, heart rate and oxygen saturation (SpO2) were recorded for two minutes. RESULTS: After maximal dynamic apnoea, SpO2 was significantly decreased (from mean 97.3% pre-dive to mean 63.1% post-dive; P < 0.0001; η2 P = 0.86), but this acute hypoxaemia did not trigger changes in SS (post-dive value 102% of baseline; P = 0.22; η2 P = 0.03). Pearson correlation analysis revealed a moderate association between SS with swimming speed (r = 0.423) and apnoea time (r = -0.404). CONCLUSIONS: A maximal dynamic apnoea did not produce changes in central nervous system fatigue or cortical arousal. We found no relationship between the hypoxaemia level reached after a maximal apnoea and changes in the CFFF thresholds. This study suggests that the time of exposure to hypoxia during a maximal voluntary apnoea is not enough to produce changes in SS.

Optimizing energy expenditure and oxygenation toward ventilator tolerance is associated with lower ventilator and intensive care unit days.

BACKGROUND: We hypothesize that if both energy expenditure and oxygenation are optimized (EEOO) toward ventilator tolerance, this would provide patients with the best condition to be liberated from the ventilator. We defined ventilator tolerance as having a respiratory quotient value between 0.7 and 1.0 while maintaining saturations above 98% with FIO2 70% or less and a normal respiratory rate without causing disturbances to the patient's pH. METHODS: This is a single-institution prospective cohort study of ventilator dependent patients within a closed trauma intensive care unit (ICU). The study period was over 52 months. A total of 1,090 patients were part of the primary analysis. The test group (EEOO) was compared to a historical cohort, comparing 26 months in each study group. The primary outcome of this study was number of ventilator days. Secondary outcomes included in-hospital mortality, ICU length of stay (LOS), overall hospital length of stay, tracheostomy rates, reintubation rates, and in-hospital complication rates, such as pneumonia and Acute Respiratory Distress Syndrome (ARDS) ARDS. Both descriptive and multivariable regression analyses were performed to compare the effects of the EEOO protocol with our standard protocols alone. RESULTS: The primary outcome of number of ventilator days was significantly shorter the EEOO cohort by nearly 3 days. This was significant even after adjustment for age, sex, race, comorbidities, nutrition type, and injury severity, (4.3 days vs. 7.2 days, p = 0.0001). The EEOO cohort also had significantly lower ICU days, hospital days, and overall complications rates. CONCLUSION: Optimizing the patient's nutritional regimen to ventilator tolerance and optimizing oxygenation by means of targeted pulmonary mechanics and inspired FIO2 may be associated with lower ventilator and ICU days, as well as overall complication rates. LEVEL OF EVIDENCE: Therapeutic, Level IV.

Assessment of a storage system to deliver uninterrupted therapeutic oxygen during power outages in resource-limited settings.

Access to therapeutic oxygen remains a challenge in the effort to reduce pneumonia mortality among children in low- and middle-income countries. The use of oxygen concentrators is common, but their effectiveness in delivering uninterrupted oxygen is gated by reliability of the power grid. Often cylinders are employed to provide continuous coverage, but these can present other logistical challenges. In this study, we examined the use of a novel, low-pressure oxygen storage system to capture excess oxygen from a concentrator to be delivered to patients during an outage. A prototype was built and tested in a non-clinical trial in Jinja, Uganda. The trial was carried out at Jinja Regional Referral Hospital over a 75-day period. The flow rate of the unit was adjusted once per week between 0.5 and 5 liters per minute. Over the trial period, 1284 power failure episodes with a mean duration of 3.1 minutes (range 0.08 to 1720 minutes) were recorded. The low-pressure system was able to deliver oxygen over 56% of the 4,295 power outage minutes and cover over 99% of power outage events over the course of the study. These results demonstrate the technical feasibility of a method to extend oxygen availability and provide a basis for clinical trials.