Search

Oxygen therapy is widely used in the community for patients with chronic hypoxaemia. Although only a small proportion of those are children, more and more paediatric patients are prescribed home oxygen for a variety of indications, most commonly for chronic lung disease related to premature birth. Chronic hypoxaemia in children is diagnosed using pulse oximetry, a method that has limitations, but alternative tests are rarely required. Whilst there are clear advantages in therapy with oxygen outside the hospital setting, clinicians need to be aware of potential impact on family life, housing, school attendance and travel. The process of prescribing is standardised in the UK, and it is crucial for clinicians to understand risks and equipment used to deliver oxygen in the community. Regular follow up is important and input from community-based professionals is hugely beneficial. Some children on long-term oxygen therapy may be able to wean and eventually stop therapy. This process can be supported by a structured protocol. New technologies such as remote monitoring may further improve the care of children with chronic conditions that require long term oxygen therapy. [ABSTRACT FROM AUTHOR]

Evidence exists for the use of high-flow nasal oxygen (HFNO) in the general critical care population for acute hypoxemic respiratory failure. There is discord between guidelines for hypoxemia management in COVID-19. Both noninvasive management and intubation present risk to patients and staff and potentially overwhelm hospital mechanical ventilator capacity. The use of HFNO has been particularly controversial in the UK, with oxygen infrastructure failure. We discuss our experience of managing COVID-19 with HFNO and awake self-prone positioning. We focus upon the less-usual case of an eighteen-year-old female to illustrate the type of patient where HFNO may be used when perhaps earlier intubation once was. It is important to consider the wider implications of intubation. We have used HFNO as a bridge to intubation or as definitive management. As we await clinical trial evidence, HFNO with self-prone positioning has a role in COVID-19 for certain patients. Response parameters must be set and reviewed, oxygen infrastructure considered, and potential staff droplet exposure minimised. [ABSTRACT FROM AUTHOR]

Objective: To compare the carbon footprint of caesarean and vaginal birth., Design: Life cycle assessment (LCA)., Setting: Tertiary maternity units and home births in the UK and the Netherlands., Population: Birthing women., Methods: A cradle-to-grave LCA using openLCA software to model the carbon footprint of different modes of delivery in the UK and the Netherlands., Main Outcome Measures: 'Carbon footprint' (in kgCO 2 equivalents [kgCO 2 e])., Results: Excluding analgesia, the carbon footprint of a caesarean birth in the UK was 31.21 kgCO 2 e, compared with 12.47 kgCO 2 e for vaginal birth in hospital and 7.63 kgCO 2 e at home. In the Netherlands the carbon footprint of a caesarean was higher (32.96 kgCO 2 e), but lower for vaginal birth in hospital and home (10.74 and 6.27 kgCO 2 e, respectively). Emissions associated with analgesia for vaginal birth ranged from 0.08 kgCO 2 e (with opioid analgesia) to 237.33 kgCO 2 e (nitrous oxide with oxygen). Differences in analgesia use resulted in a lower average carbon footprint for vaginal birth in the Netherlands than the UK (11.64 versus 193.26 kgCO 2 e)., Conclusion: The carbon footprint of a caesarean is higher than for a vaginal birth if analgesia is excluded, but this is very sensitive to the analgesia used; use of nitrous oxide with oxygen multiplies the carbon footprint of vaginal birth 25-fold. Alternative methods of pain relief or nitrous oxide destruction systems would lead to a substantial improvement in carbon footprint. Although clinical need and maternal choice are paramount, protocols should consider the environmental impact of different choices., (© 2024 The Authors. BJOG: An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd.)

Introduction: Sickle cell disease (SCD) is one of the most common inherited diseases worldwide. It is associated with lifelong morbidity and reduced life expectancy. Hydroxyurea (HU) has been shown to reduce the frequency and severity of vaso-occlusive episodes in SCD. Hypoxaemia and intermittent nocturnal oxygen desaturations occur frequently in children with SCD and contribute to the associated morbidity, including risk of cerebrovascular disease.Objective: To evaluate the effect of HU on oxygen saturation (SpO2) overnight and on daytime SpO2 spot checks in children with SCD.Methods: A retrospective review of children with SCD and respiratory problems who attended two UK tertiary sickle respiratory clinics and were treated with HU. Longitudinal data were collected from 2 years prior and up to 3 years after the commencement of HU.Results: Forty-three children, 23 males (53%) with a median age of 9 (range 1.8-18) years were included. In the 21 children who had comparable sleep studies before and after starting HU, mean SpO2 was higher (95.2% from 93.5%, p=0.01) and nadir SpO2 was higher (87.2% from 84.3%, p=0.009) when taking HU. In 32 of the children, spot daytime oxygen saturations were also higher (96.3% from 93.5%, p=0.001).Conclusion: Children with SCD had higher oxygen saturation overnight and on daytime spot checks after starting HU. These data suggest HU may be helpful for treating persistent hypoxaemia in children with SCD pending more evidence from a randomised clinical trial. [ABSTRACT FROM AUTHOR]

Background: Heated Humidified High Flow Nasal Cannula Oxygen Therapy (HHFNC) is increasingly used on the paediatric wards and High Dependency Units (HDU) for different types of pathologies and different age groups. We aimed to describe current practice related to the use of HHFNC on the paediatric wards and HDUs, weaning practices and preferred outcome measures for future research.Methods: We carried out a cross-sectional online survey of UK paediatric consultants or their delegates working on the paediatric wards. Descriptive analysis of their geographical, and organizational characteristics, their specialties, and their level of experience was investigated. Reasons for HHFNC initiation, weaning criteria, patients' characteristics and their primary pathologies were also analysed.Results: Participation of 218 paediatricians from 81 hospitals (Median: 2.7, Range: 1-11) was registered. HHFNC was provided in most of the surveyed hospitals (93%, 75/81). A High Dependency Unit (HDU) was available in 47 hospitals (58%); less than a third of those have a dedicated paediatrician. Decisions around HHFNC were made solely by paediatricians in (75%) of the cases, mostly at hospitals with no HDU compared to those with dedicated HDUs (70.3% VS 36.6, 95%CI:22.6-50.4%, P < .001). HHFNC was reported by nearly two-thirds (68%) of the practitioners who used it on the wards to be as effective or superior to CPAP (Continuous Positive Airway Pressure) with fewer complications. Failure rate while on HHFNC was identified as the most important outcome measure in any future research followed by the length of need for HHFNC support (37.1, and 28% respectively).Conclusion: This survey showed support for developing paediatric-specific national guidance on the use of HHFNC on the wards. Our list of defined research priorities may help guide further collaborative research efforts in this field. [ABSTRACT FROM AUTHOR]

Objectives: To calculate fractional inspired oxygen concentration (FiO2) thresholds in ward patients and add these to the National Early Warning Score (NEWS). To evaluate the performance of NEWS-FiO2 against NEWS when predicting in-hospital death and unplanned intensive care unit (ICU) admission.Methods: A multi-centre, retrospective, observational cohort study was carried out in five hospitals from two UK NHS Trusts. Adult admissions with at least one complete set of vital sign observations recorded electronically were eligible. The primary outcome measure was an 'adverse event' which comprised either in-hospital death or unplanned ICU admission. Discrimination was assessed using the Area Under the Receiver Operating Characteristic curve (AUROC).Results: A cohort of 83,304 patients from a total of 271,363 adult admissions were prescribed oxygen. In this cohort, NEWS-FiO2 (AUROC 0.823, 95% CI 0.819-0.824) outperformed NEWS (AUORC 0.811, 95% CI 0.809-0.814) when predicting in-hospital death or unplanned ICU admission within 24 h of a complete set of vital sign observations.Conclusions: NEWS-FiO2 generates a performance gain over NEWS when studied in ward patients requiring oxygen. This warrants further study, particularly in patients with respiratory disorders. [ABSTRACT FROM AUTHOR]

Objective: To assess the effectiveness and adverse effects of acute cluster headache medications in a large international sample, including recommended treatments such as oxygen, commonly used medications such as opioids, and emerging medications such as intranasal ketamine. Particular focus is paid to a large subset of respondents 65 years of age or older. Background: Large international surveys of cluster headache are rare, as are examinations of treatments and side effects in older cluster headache patients. This article presents data from the Cluster Headache Questionnaire, with respondents from over 50 countries and with the vast majority from the United States, the United Kingdom, and Canada. Methods: This internet‐based survey included questions on cluster headache diagnostic criteria, which were used as part of the inclusion/exclusion criteria for the study, as well as effectiveness of medications, physical and medical complications, psychological and emotional complications, mood scores, and difficulty obtaining medications. The diagnostic questions were also used to create a separate group of respondents with probable cluster headache. Limitations to the methods include the use of nonvalidated questions, the lack of a formal clinical diagnosis of cluster headache, and the grouping of some medications (eg, all triptans as opposed to sumatriptan subcutaneous alone). Results: A total of 3251 subjects participated in the questionnaire, and 2193 respondents met criteria for this study (1604 cluster headache and 589 probable cluster headache). Of the respondents with cluster headache, 68.8% (1104/1604) were male and 78.0% (1245/1596) had episodic cluster headache. Over half of respondents reported complete or very effective treatment for triptans (54%, 639/1139) and oxygen (54%, 582/1082). Between 14 and 25% of respondents reported complete or very effective treatment for ergot derivatives (dihydroergotamine 25%, 42/170; cafergot/ergotamine 17%, 50/303), caffeine and energy drinks (17%, 7/41), and intranasal ketamine (14%, 5/37). Less than 10% reported complete or very effective treatment for opioids (6%, 30/541), intranasal capsaicin (5%, 7/151), and intranasal lidocaine (2%, 5/241). Adverse events were especially low for oxygen (no or minimal physical and medical complications 99%, 1077/1093; no or minimal psychological and emotional complications 97%, 1065/1093), intranasal lidocaine (no or minimal physical and medical complications 97%, 248/257; no or minimal psychological and emotional complications 98%, 251/257), intranasal ketamine (no or minimal physical and medical complications 95%, 38/40; no or minimal psychological and emotional complications 98%, 39/40), intranasal capsaicin (no or minimal physical and medical complications 91%, 145/159; no or minimal psychological and emotional complications 94%, 150/159), and caffeine and energy drinks (no or minimal physical and medical complications 89%, 39/44; no or minimal psychological and emotional complications 91%, 40/44). This is in comparison to ergotamine/cafergot (no or minimal physical and medical complications 83%, 273/327; no or minimal psychological and emotional complications 89%, 290/327), dihydroergotamine (no or minimal physical and medical complications 81%, 143/176; no or minimal psychological and emotional complications 91%, 160/176), opioids (no or minimal physical and medical complications 76%, 416/549; no or minimal psychological and emotional complications 77%, 423/549), or triptans (no or minimal physical and medical complications 73%, 883/1218; no or minimal psychological and emotional complications 85%, 1032/1218). A total of 139 of 1604 cluster headache respondents (8.7%) were age 65 and older and reported similar effectiveness and adverse events to the general population. The 589 respondents with probable cluster headache reported similar medication effectiveness to respondents with a full diagnosis of cluster headache. Conclusions: Oxygen is reported by survey respondents to be a highly effective treatment with few complications in cluster headache in a large international sample, including those 65 years or over. Triptans are also very effective with some side effects, and newer medications deserve additional study. Patients with probable cluster headache may respond similarly to acute medications as patients with a full diagnosis of cluster headache. [ABSTRACT FROM AUTHOR]

Objective: Examine admissions for bronchiolitis, comparing centres with oxygen saturation thresholds for admission of 90% versus 92%.Design: Prospective multi-centre service evaluation, all admissions for bronchiolitis during 4-week period, November 2018.Setting: Paediatric departments across 12 hospitals in the West Midlands, UK.Patients: 320 patients aged 6 weeks-1 year, diagnosis of bronchiolitis, exclusions: chronic illness or high dependency/intensive care admission.Main Outcome Measures: Reason for admission, admission saturations and length of stay.Results: Inadequate feeding was the the most common reason for admission (80%). Only 20 patients were admitted solely because of low saturations. Median peripheral oxygen saturation in this group was 88%. Median length of stay in 90% centres was 41 hours, against 59 hours for 92% centres (p=0.0074).Conclusions: Few patients were admitted solely due to low oxygen saturations, only one had a potentially avoidable admission if thresholds were 90%. Length of stay was significantly reduced in the 90% threshold centres. [ABSTRACT FROM AUTHOR]

Differences in the diagnostic approach to bronchopulmonary dysplasia (BPD) may contribute to variation in reported BPD rates. We undertook a nationwide survey of UK neonatal units (NNUs) to describe criteria applied by neonatologists to conduct pulse oximetry studies in ex-preterm infants to assess their need for supplemental oxygen near discharge, as well as criteria applied to interpret saturation studies. Responses from 112 (64.7%) NNUs demonstrated wide variation in both criteria used to select infants for assessment and thresholds for interpretation. Neither demonstrated a clear relationship with reported BPD rates. Variation in clinical practice requires further scrutiny to inform and streamline management of ex-preterm infants at risk of BPD, and potentially improve outcomes., Competing Interests: Declaration of Competing Interest No conflict., (Copyright © 2023 SPLF and Elsevier Masson SAS. All rights reserved.)

Background: The 'classical' technique of rapid sequence induction (RSI) of anaesthesia was described in 1970. With the introduction of new drugs and equipment in recent years, a wide variation in this technique has been used. The role of cricoid pressure is controversial because of the lack of scientific evidence. Moreover, gentle mask ventilation has been recommended in situations such as obesity and critically ill patients, to prevent hypoxaemia during the apnoeic period. In identifying multiple techniques, we conducted a national postal survey to establish the current practice of RSI in the UK.Methods: A survey consisting of 17 questions was created and posted to 255 National Health Service (NHS) hospitals in the UK. We included two copies of the questionnaire in each envelope; one to be completed by the airway lead (consultant anaesthetist with responsibility of overseeing the standard of airway training and implementing national airway guidelines and recommendations within their institution) and the other by a trainee in the same department. The difference in responses from consultants and trainees were assessed using the χ(2) test and the Fisher's exact test.Results: In total we received 272 responses (response rate 53%) of which 266 (58% from consultants and 42% from trainees) were analysed. A majority of the respondents (68%) pre-oxygenated by monitoring end-tidal oxygen concentration and 76% of the respondents use 20-25° head up tilt for all RSIs. Propofol is the most commonly used induction agent (64% of all respondents). Opioid has been used by 80% of respondents and only 18% of respondents use suxamethonium for all patients and others choose rocuronium or suxamethonium based on clinical situation. Although 92% of anaesthetists use cricoid pressure, 83% of them never objectively measure the force used. During the apnoeic period 17% of the respondents use gentle mask ventilation.Conclusions: Our survey demonstrated a persistent variation in the practice of RSI amongst the anaesthetists in the UK. The 'classical' technique of RSI is now seldom used. Therefore there is a clear need for developing consistent guidelines for the practice of RSI. [ABSTRACT FROM AUTHOR]

Aim: The aim of this multi-centre observational evaluation was to assess the percentage reduction in wound area of non-healing diabetic foot ulcers (DFUs), treated with Granulox haemoglobin spray over a 4-week period. Secondary outcome parameters-for example, adverse events, patient acceptability and ease of use-were also recorded. Method: After a runin- period (2 weeks for existing patients and 4 weeks for new patients) to determine if the wounds were non-healing despite receiving local best practice, patients whose foot ulcers had decreased in size by < 20% were then entered into the evaluation. A sample of 17 patients (4 females and 13 males), comprising 4 with type 1 and 13 with type 2 diabetes, with a total of 20 DFUs, met the inclusion criteria. These data were collected from six sites across the UK. Results: There was an overall positive reduction in size in 15 of the wounds, equating to a mean reduction of 53.8% (standard deviation (SD): 26.6; range: 11.9-100%). One participant, with two ulcers, had to be withdrawn due to infection. All clinicians and participants found the product easy to use. Conclusion: The addition of a topical oxygenation therapy in this cohort of non-healing DFUs showed reduction in wound surface area and progression to healing. The product was also found to be acceptable and very easy to use by both participants and clinicians. [ABSTRACT FROM AUTHOR]

Background: The safest ranges of oxygen saturation in preterm infants have been the subject of debate.Methods: In two trials, conducted in Australia and the United Kingdom, infants born before 28 weeks' gestation were randomly assigned to either a lower (85 to 89%) or a higher (91 to 95%) oxygen-saturation range. During enrollment, the oximeters were revised to correct a calibration-algorithm artifact. The primary outcome was death or disability at a corrected gestational age of 2 years; this outcome was evaluated among infants whose oxygen saturation was measured with any study oximeter in the Australian trial and those whose oxygen saturation was measured with a revised oximeter in the U.K. trial.Results: After 1135 infants in Australia and 973 infants in the United Kingdom had been enrolled in the trial, an interim analysis showed increased mortality at a corrected gestational age of 36 weeks, and enrollment was stopped. Death or disability in the Australian trial (with all oximeters included) occurred in 247 of 549 infants (45.0%) in the lower-target group versus 217 of 545 infants (39.8%) in the higher-target group (adjusted relative risk, 1.12; 95% confidence interval [CI], 0.98 to 1.27; P=0.10); death or disability in the U.K. trial (with only revised oximeters included) occurred in 185 of 366 infants (50.5%) in the lower-target group versus 164 of 357 infants (45.9%) in the higher-target group (adjusted relative risk, 1.10; 95% CI, 0.97 to 1.24; P=0.15). In post hoc combined, unadjusted analyses that included all oximeters, death or disability occurred in 492 of 1022 infants (48.1%) in the lower-target group versus 437 of 1013 infants (43.1%) in the higher-target group (relative risk, 1.11; 95% CI, 1.01 to 1.23; P=0.02), and death occurred in 222 of 1045 infants (21.2%) in the lower-target group versus 185 of 1045 infants (17.7%) in the higher-target group (relative risk, 1.20; 95% CI, 1.01 to 1.43; P=0.04). In the group in which revised oximeters were used, death or disability occurred in 287 of 580 infants (49.5%) in the lower-target group versus 248 of 563 infants (44.0%) in the higher-target group (relative risk, 1.12; 95% CI, 0.99 to 1.27; P=0.07), and death occurred in 144 of 587 infants (24.5%) versus 99 of 586 infants (16.9%) (relative risk, 1.45; 95% CI, 1.16 to 1.82; P=0.001).Conclusions: Use of an oxygen-saturation target range of 85 to 89% versus 91 to 95% resulted in nonsignificantly higher rates of death or disability at 2 years in each trial but in significantly increased risks of this combined outcome and of death alone in post hoc combined analyses. (Funded by the Australian National Health and Medical Research Council and others; BOOST-II Current Controlled Trials number, ISRCTN00842661, and Australian New Zealand Clinical Trials Registry number, ACTRN12605000055606.). [ABSTRACT FROM AUTHOR]

Background: The role of oxygen therapy to palliate dyspnoea is controversial. Without a clear evidence base oxygen is commonly prescribed, sometimes to the detriment of patients. This use of oxygen appears to be an entrenched culture, the roots of which remain obscure. Aim: To explore healthcare professionals’ perceptions of oxygen therapy in palliative care. Design: Interpretative phenomenological analysis study utilising semi-structured interviews to explore beliefs and behaviours of healthcare professionals regarding palliative oxygen therapy. Data were recorded, transcribed and analysed using interpretative phenomenological analysis. Setting/participants: A total of 34 healthcare professionals, including doctors, nurses, pharmacists and paramedics in the United Kingdom, who were involved in prescribing, or administering, oxygen therapy to palliate dyspnoea. Results: Most healthcare professionals in this study were well informed about oxygen therapy; all recognised the role of oxygen in palliative care setting as important. The overarching theme of compassion identified sub-themes of ‘comfort’, ‘do anything and everything’ and ‘family benefit’. However, the use of oxygen in the palliative care setting was not without its dilemmas, as additional sub-themes of ‘controversy’, ‘doubt’ and ‘dependency’ illustrated. Conclusion: Findings suggest that oxygen therapy in palliative care poses an on-going dilemma for healthcare professionals striving to provide optimum care. It seems patients and families often expect and welcome oxygen, but the perception of oxygen as a solution to dyspnoea can conflict with healthcare professionals’ own doubt and experiences. There appears to be an emotional cost associated with this dilemma and the choices that need to be made. [ABSTRACT FROM AUTHOR]

Arterialised ear lobe capillary blood (ELCB) gas sampling is a widely used clinical procedure undertaken across both primary and secondary care settings. The prevalence of this sampling method has grown among health professionals, coupled with a growing demand for domiciliary oxygen therapy in the UK, in particular for those who have chronic obstructive pulmonary disease (COPD). Research studies supporting arterialised ELCB gas sampling show inconsistencies in technique, and a survey o f respiratory nurses’ current practice demonstrated wider inconsistencies. In the absence of national clinical guidelines to direct this practice, and an acknowledged and accepted under-calculation of partial pressure of oxygen, this article investigates the sampling method used to obtain arterialised ELCB gas sampling and consequently questions its reliability in practice. [ABSTRACT FROM AUTHOR]

Aim Heated humidified high-flow nasal cannula ( HHHFNC) oxygen is a relatively new form of respiratory support and is increasing in popularity despite lack of supportive evidence and amid safety concerns. We investigated the prevalence of its use in tertiary neonatal units in the UK. Method Electronic survey. Results A total of 57 units were contacted and replies received from 44 (77%). HHHFNC was used in 34/44 (77%) units. Vapotherm 2000i and Fisher and Paykel RT329 were the most popular devices. 39% units used HHHFNC without policies. Most reported use in infants of any gestation (24/34, 71%) and weight (26/34, 77%) and for a variety of indications including as an alternative to CPAP (26/34, 77%), weaning off CPAP (24/34, 71%) and postextubation (18/34, 53%). The flow rates, cannula size and mouth position varied widely. The popularity of HHHFNC appeared to be its perceived ease of use and improved access to the baby. Conclusion This survey demonstrates that HHHFNC is a widely used modality in UK neonatal units. Its current use appears to be without clear criteria and mostly based on individual preference. In view of doubts about its efficacy and concerns regarding safety, this study highlights the urgent need for research to evaluate its use in newborns. [ABSTRACT FROM AUTHOR]

Treponematosis has been one of the most studied and debated infectious diseases in paleopathology, particularly from the standpoint of its origin, evolution, and transmission. This study links evidence for treponematosis in skeletons from the 14th-16th century AD cemetery of the Augustinian friary of Hull Magistrates Court, England, with data from stable isotope analysis to test the hypothesis that the people with treponemal disease buried at this site were not locally born and raised. The objective is to explore the potential of using stable isotope data to track the place of origin and extent of mobility of individuals with an infectious disease. Dental enamel samples of 12 skeletons were selected for strontium (87Sr/86Sr ratio) and oxygen (δ18O) stable isotope analysis based on the presence (six - diseased) or absence (six - controls) of bone changes associated with treponemal disease. The oxygen isotope ratios of all but three individuals (1047, 1121, 823) overlapped at two standard deviations with the inferred local precipitation range, and only one individual (1216) had a strontium isotope ratio outside the regional range. Two of the four had probable/possible treponemal bone changes. Those with treponemal bone changes were not demonstrably more likely to be migrants than those without such lesions. However, because of extensive documentary evidence for trade with the Baltic Sea area, and for merchants from towns such as Stralsund, Danzig and Elbing being in Hull, it is very plausible that the four migrants came from the Baltic area or even southern Sweden. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In this work, oxygen enriched air combustion is addressed. A 0·5 MW Doosan-Babcock burner was used and fired on the RWE npower combustion test facility located on the site of the Didcot 'A' Power Station in the UK. The present work concentrated on radiative and convective heat transfer measurements. Oxygen enrichment levels varied between circa 19 and 30% (v/v), dependent on the amount of recycled flue gas to give a constant furnace exit O2 level of 3%, although the furnace exit O2 was varied for carbon-in-ash measurements. Air was also used as comburent for baseline data acquisition. The recycled flue gas was dry and a Russian coal was fired. The results of this work has shown that oxygen enriched air combustion is a viable technique for carbon capture and storage providing CO2 enriched flue gas that will reduce the size of an amine scrubbing plant. The reduced level of oxygen enrichment compared to pure oxyfuel combustion also reduces the potential size of an air separation unit. [ABSTRACT FROM AUTHOR]

There is considerable controversy concerning the benefits and risks of oxygen treatment in many situations and healthcare professionals receive conflicting advice about safe oxygen use. The British Thoracic Society (BTS) has published up-to-date, evidence-based guidelines for emergency oxygen use in the UK in order to encourage the safe use of oxygen in emergency situations and improve consistency of clinical practice. 1 The purpose of this concise guideline is to summarise the key recommendations, particularly concerning emergency oxygen use in the hospital setting. [ABSTRACT FROM AUTHOR]

Abstract: We aimed to find out the number of patients with osteoradionecrosis (ORN) being treated by hyperbaric chambers in the UK during 2006-07, and the protocols that were being used. We did a telephone survey of 76 chambers to find out whether they treated patients with ORN, how many patients they treated in 2006–07, what chamber pressure they used, the duration of each session, and the total number of sessions/patient. A total of 25 chambers treated 273 patients with ORN in 2006–07; 10 were listed by the British Hyperbaric Association (BHA) and 15 were at multiple sclerosis (MS) centres. MS centres treated 23 (8%) of patients with ORN with a variable number of sessions of shorter duration and lower pressures than the chambers listed by the BHA. Most BHA chambers treated patients at 2.2 ATA for 90min/session with 30 preoperative and 10 postoperative sessions/patient. [Copyright &y& Elsevier]

Abstract: Doosan Babcock is aiming to develop a competitive oxyfuel firing technology suitable for full plant application post 2010, and is taking a phased approach to the development and demonstration of oxyfuel technology. Doosan Babcock is leading a number of UK Government supported collaborative projects that are developing oxyfuel combustion technology. The “Fundamentals and Underpinning Technologies” project aims to develop a competitive oxyfuel firing process based on the integration of well proven and innovative power plant design components, addressing critical technology gaps such as combustion fundamentals, furnace design and operation, novel flue gas purification technologies and generic process issues. The “Demonstration of an Oxyfuel Combustion System” project aims to demonstrate an oxyfuel combustion system of a type and size (40MWt) applicable to new build and retrofit advanced supercritical boiler plant. These two projects are discussed in the paper and preliminary results from pilot-scale testing undertaken in the first of these are presented. [Copyright &y& Elsevier]

[Display omitted] • Water quality was assessed in a slow-flowing lowland river by a process-based model. • National data sources supplemented by local observations informed the assessment. • The capability of the model to simulate response to changes in flow was analysed. • Local knowledge substantially improved temperature and dissolved oxygen simulation. • Hourly dissolved oxygen is only modelled reliably with local hydraulic information. Water quality in lowland rivers is sensitive to changes in flow during summer dry periods, when high temperatures and low pollutant dilution are problematic and may reduce oxygen concentrations to levels of ecological concern. A 10-year period of monitoring data was collated for a typical small lowland UK river. Two hourly-resolution applications of a process-based water quality model (QUESTOR) were made, with and without local knowledge, to establish whether specific information on stream channel hydraulics is an essential precursor to successful simulation. Results showed this information to be necessary, with considerably better goodness-of-fit statistics obtained when the local knowledge was used. In this regard, mean improvements in Nash-Sutcliffe Efficiency across all monitoring sites were from −0.33 to 0.18 and from 0.24 to 0.78 for dissolved oxygen and water temperature respectively. Percent bias was within 10% for the local model. The 10-year record also allowed a detailed characterisation of how changes in flow, as described by a comprehensive range of Indicators of Hydrological Alteration, relate to the water quality determinants. Analysis revealed these dynamics were also captured more realistically when the model was driven by local knowledge. The research concludes that river dissolved oxygen simulations driven by national-level information are of some value as screening tools, but model refinement supported by sufficient provision of local information is necessary when detailed simulations are required to support specific decision-making. [ABSTRACT FROM AUTHOR]

Background: There is an increasing awareness of the role of oxygen free radicals in the pathogenesis of many conditions associated with prematurity, which has led to caution in the use of oxygen in neonatal resuscitation. We surveyed the practice of UK pediatric anesthetists with regard to oxygen use in neonatal and infant anesthesia. Methods: A postal questionnaire survey of 460 UK-based members of the Association of Pediatric Anesthetists of Great Britain and Ireland. Results: Responses were received from 247 pediatric anesthetists (54%). Seventy-five percent of anesthetists aim to avoid the use of 100% oxygen during routine infant anesthesia and 52% aim for an FiO2 of < 0.4 in neonates. The factors most influencing choice of carrier gas are optimal oxygenation and the avoidance of pulmonary atelectasis. Sixteen percent stated that unavailability of medical air is a factor. Opinion was divided on concern about the effects of anesthetic agents on the developing brain. Moderate levels of concern were expressed about the potential toxic effects of oxygen on the eyes and lungs of premature newborns but this concern does not extend to term newborns. Only 20% of anesthetists had any recent knowledge of these issues. Conclusions: This survey indicates that there is no consistency in attitudes and practices and demonstrates considerable variation in the use of oxygen during anesthesia in premature and newborn babies and infants. This may reflect the paucity of evidence in the anesthetic literature on the potential harmful effects of high concentrations of oxygen in vulnerable groups of infants. [ABSTRACT FROM AUTHOR]

1. Hydroacoustics (2002–04) and long-term oxygen data (1969–2004) have been used in conjunction to examine the habitat of Arctic charr in the north and south basins of Windermere, U.K., a temperate lake subjected to cultural eutrophication and subsequent nutrient management. 2. Since 1969 there has been a gradual decline in the oxygen concentration in the bottom waters of both basins of 0.03–0.04 mg L−1year−1, resulting in up to 43% of the volume of the south basin having an oxygen concentration <5 mg L−1 in the early autumn. 3. Hydroacoustic data indicate that most Arctic charr routinely avoid the upper 10 m of the water column irrespective of temperature, with the implication that an observed gradual warming of the lake has not yet directly impacted upon their habitat. 4. In recent years there has been a behavioural response of the Arctic charr population to migrate vertically to avoid oxygen concentrations <2.3–3.1 mg L−1. Further, the depth of the lower bound of the Arctic charr population is shown to be highly correlated with the deep water oxygen concentration throughout the year prior to autumnal overturn. [ABSTRACT FROM AUTHOR]

The benefits of long-term oxygen therapy (LTOT) on mood in Chronic Obstructive Pulmonary Disease (COPD) are unproven. Longitudinal studies are affected by disease progression, the increased package of care (with LTOT) and may not control for known confounders on mood. We compared the point prevalence and severity of mood disturbance in patients with severe COPD, not on LTOT (the -LTOT group) to those with COPD on LTOT (the +LTOT group). We mailed the Hospital Anxiety and Depression (HAD) Score to 182 consecutive patients with severe COPD, identified from respiratory case notes in three UK Hospitals. We compared 57 patients not prescribed LTOT to 57 patients on LTOT, and used stratified sampling to match the groups as far as possible for age, gender, lung function and other possible confounders on mood. Or these, 25% of patients in both groups scored in the 'definite' case range for anxiety (HAD score ≥ 11). 37% of the -LTOT group and 33% of the +LTOT group scored in the 'definite' range for depression (HAD score ≥ 11) (p = N.S). In both groups, only 11% of responders were prescribed anxiolytics and/or antidepressants. Further multiregression analysis confirmed that socio-demographic variables (e.g., lives alone, feels isolated or recent life events) were stronger predictors of mood than the prescription of LTOT or other traditionally accepted factors such as co-morbidity or the use of antidepressants or anxiolytics. High levels of anxiety and depression are present in severe COPD and appear under-treated. The +LTOT and -LTOT patients had a similar high prevalence of anxiety and depression. [ABSTRACT FROM AUTHOR]

Sleep nasendoscopy was conceived at the Royal National Throat, Nose and Ear Hospital, UK in 1991, and has remained fully implemented in patient selection for targeted treatment of the spectrum of sleep-disordered breathing. The senior authors (B.T.K. and P.B.) have been performing sleep nasendoscopy together for over 10 years, and we look back at their decade’s experience. A retrospective audit study based on case notes was performed over a 10-year period (1995–2005) in a tertiary-referral practice setting. Case notes were retrieved on all patients who had undergone sleep nasendoscopy during the study period, and agreed data were extracted and analyzed. A total of 2,485 sleep nasendoscopies were performed in patients with a mean age of 44.1 years, a 4:1 male preponderance, and a mean body mass index of 27.3 kg m−2. Sleep nasendoscopy grading correlated well with apnoea–hypopnoea index and mean oxygen desaturation. Such grading helped us define and discuss treatment options with patients. After a median follow-up period of 518 days, 72% of patients reported feeling better; 26% of patients reported no change; and only 2% of patients reported feeling worse after treatment. Sleep nasendoscopy has proved to be a useful adjunctive method to identify the anatomical site of snoring, not to mention upper airway collapse, and remains integral to our tertiary-referral practice. It has allowed us quality assessment of the dynamic anatomy of sleep-disordered breathing that most closely and cost-effectively simulates the natural situation of patients. And for targeted treatment, such assessment has been fundamental. [ABSTRACT FROM AUTHOR]

A method of model evaluation is presented which utilises a comparison with a benchmark model. The proposed benchmarking concept is one that can be applied to many hydrological models but, in this instance, is implemented in the context of an in-stream water quality model. The benchmark model is defined in such a way that it is easily implemented within the framework of the test model, i.e. the approach relies on two applications of the same model code rather than the application of two separate model codes. This is illustrated using two case studies from the UK, the Rivers Aire and Ouse, with the objective of simulating a water quality classification, general quality assessment (GQA), which is based on dissolved oxygen, biochemical oxygen demand and ammonium. Comparisons between the benchmark and test models are made based on GQA, as well as a step-wise assessment against the components required in its derivation. The benchmarking process yields a great deal of important information about the performance of the test model and raises issues about a priori definition of the assessment criteria. [ABSTRACT FROM AUTHOR]

George F Winter weighs in on pulse oximetry screening as an effective method of testing for critical congenital heart defects in newborns [ABSTRACT FROM AUTHOR]

The article presents a Paschen characteristics formula with appropriate constants of gases use for high voltage technology in Great Britain. In the study, the researchers used the primary and secondary ionization coefficients to obtain the characteristics of these gases. It demonstrates that at high pressure gas distance, the breakdown mechanism takes place in hydrogen, nitrogen, oxygen and carbon dioxide, while the sparkling occurs in the air.

Following a request from a Governmental Interdepartmental Group, the Health and Safety Executive undertook a polychlorinated dibenzo-p-dioxin (PCDD) and polychorinated dibenzofuran (PCDF) sampling exercise at several work sites in the UK. An initial survey suggested potential PCDD/F production at metal recycling sites, during cement manufacture, at municipal waste incinerators and landfill sites and during the use of thermal oxygen lances. PCDD/F sampling, using static and personal air samplers, revealed that the highest PCDD/F exposures were found at metal recycling sites, particularly aluminium recycling sites. The reasons for these results and the possible consequential intakes are discussed. [ABSTRACT FROM AUTHOR]

Reconstruction of the hydrocarbon filling history of a reservoir is important for prediction of field-scale porosity and permeability, and for the calibration of basin models. Published histories of the Brent Group show only a single phase of hydrocarbon filling, which occurred after the diagenetic reactions had run their course. In contrast, diagenetic minerals preserve evidence of multiple episodes of hydrocarbon charging. In the Cormorant Field, UK North Sea, authigenic blocky kaolin shows a systematic change in oxygen isotopic composition with depth, and the trend displays a conspicuous shift at the Mid-Ness Shale, a regionally extensive permeability barrier. The isotopic data are most readily explained if kaolin recrystallisation (from earlier vermiform kaolin) was synchronous with hydrocarbon charging, with two hydrocarbon pools, one above and one below the Mid-Ness Shale. The filling history begins with a relatively early, slow, filling phase (45–70 °C; 80–50 Ma) that formed an oil column with the oil–water contact substantially below the present-day position. This first hydrocarbon subsequently leaked off, allowing renewed diagenetic activity, including the formation of quartz overgrowths with aqueous inclusions. Emplacement of the present-day hydrocarbon charge was the last event in the history of the reservoir (90–100 °C; 10–0 Ma). [Copyright &y& Elsevier]

The purpose of this study was to quantify the metabolic demand of simulated shipboard fire-fighting procedures currently practised by men and women in the Royal Navy (RN) and to identify a minimum level of cardiovascular fitness commensurate with satisfactory performance. Thirty-four males (M) and 15 females (F) volunteered as subjects for this study (n=49). Maximal oxygen uptake (VO[sub 2max]) and heart rate (fc[sub max]) of each subject was assessed during a standardized treadmill test. During the main trials, volunteers were randomly assigned to complete several 4-min simulated shipboard fire-fighting tasks (boundary cooling (BC), drum carry (DC), extinguisher carry (EC), hose run (HR), ladder climb (LC)), at a work rate that was endorsed as a minimum acceptable standard. Heart rate (fc) and oxygen uptake (VO[sub 2]) were recorded at 10-s intervals during rest, exercise and recovery. Participants completed all tasks within an allocated time with the exception of the DC task, where 11 subjects (all females) failed to maintain the endorsed work rate. The DC task elicited the highest (p<0.01) group mean peak metabolic demand (PMD) in males (43 ml min[sup -1] kg[sup -1]) and females (42 ml min[sup -1] kg[sup -1]) who were able to maintain the endorsed work rate. The BC task elicited the lowest PMD (23 ml min[sup -1] kg[sup -1]), whilst the remaining three tasks elicited a remarkably similar PMD of 38-39 ml min[sup -1] kg[sup -1]. The human endurance limit while wearing a self-contained breathing apparatus (SCBA) dictates that RN personnel are only able to fire-fight for 20-30 min, while wearing a full fire-fighting ensemble (FFE) and performing a combination of the BC, HR and LC tasks, which have a group mean metabolic demand of 32.8 ml min[sup -1] kg[sup -1]. Given that in healthy subjects fire-fighting can be sustained at a maximum work intensity of 80% VO[sub 2max] when wearing SCBA for this duration, it is recommended that all RN personnel achieve a VO[sub 2max ]of 41 ml min[sup -1] kg[sup -1] as an absolute minimum standard. Subjects with a higher VO[sub 2m ax] than the above quoted minimum are able to complete the combination of tasks listed with greater metabolic efficiency and less fatigue. [ABSTRACT FROM AUTHOR]

• Muon transfer rate from muonic hydrogen to oxygen measured at RIKEN RAL (UK). • Rise with the temperature of the muon transfer rate from muonic hydrogen to oxygen. • Use of LaBr 3 fast scintillator counters read by photomultiplier. • Important basis to measure the hyperfine splitting of muonic hydrogen. The first measurement of the temperature dependence of the muon transfer rate from muonic hydrogen to oxygen was performed by the FAMU collaboration in 2016. The results provide evidence that the transfer rate rises with the temperature in the range 104-300 K. This paper presents the results of the experiment done in 2018 to extend the measurements towards lower (70 K) and higher (336 K) temperatures. The 2018 results confirm the temperature dependence of Λ p O observed in 2016 and sets firm ground for comparison with the theoretical predictions. [ABSTRACT FROM AUTHOR]

Environmental gradients across 109 British estuaries were examined in relation to the communities of shorebirds in winter. Ordination and classification techniques were employed on the 5-year means of peak-winter high-tide counts for the 13 most common species, converted to densities, for the two periods. 1969–75 (first period) and 1981–85 (second period), in order to quantify changes in community composition between the two periods. Multiple regression within GLIM was then used to relate the DCA ordination scores to physical, climatic, geographic and water chemistry variables. In an ordination analysis of the combined data for the two periods, axis I had a left—right gradient of species favouring coastal lagoons (avocet) to those favouring sandy estuaries (bar-tailed godwit, sanderling, knot). Dunlin and grey plover (favouring muddy estuaries) occupied similar positions on the ordination as did turnstone and purple sandpiper (favouring rocky estuaries). Turnstone, purple sandpiper, redshank and oystercatcher underwent large changes in numbers between the two time periods, which affected their overall contribution to community structure. In terms of changes in community composition between periods, most estuaries have experienced little change, but a small number, e.g. Blyth (Northumberland), Axe, Auchencairn Bay/Rough Firth complex, Irt/Mite/Esk complex, and the Tweed, underwent large changes. Sites showing most change received more rainfall (Jan—Mar), had higher minimum water temperature, and lower maximum salinity. Community change was not correlated with any aspect of nutrient status. Axis 1 of the sites ordination was positively correlated with estuary size, high concentrations of ammonium-N, high biochemical oxygen demand, and negatively with rainfall, mean air and minimum water temperature, maximum salinity and mean percentage of dissolved oxygen. Axis 1 therefore represents a left—right gradient of increasing estuary size containing higher quantities of organic matter, higher oxygen demand and lower oxygen availability. Multiple regression analysis within GLIM showed the effect of these nutrient-status indicator variables operated to some extent independently of estuary size. Hierarchical classification of the 109 estuaries, based on their wader communities, revealed four groups. Group 1 represented species favouring muddy estuaries; group 4 ones with a dominance of species favouring sandy shores; groups 2 and 3 represented estuaries intermediate between these types. Stepwise discriminant analysis indicated that northing, tidal range and total estuary area were significant discriminating variables between the four groups. Estuaries in group 4 tended to have a greater area of intertidal feeding habitat and wider entrances, corresponding to large estuaries. The implications of these findings to estuary conservation and development proposals, are discussed. [ABSTRACT FROM AUTHOR]

The article highlights the need for dental care practices to have immediate access to basic equipment to enable practitioners to respond to emergencies until the arrival of emergency services. It lists some common emergency equipment that should be available in a dental practice setting, such as oxygen face mask with tubing, oropharyngeal airways, and pocket mask with oxygen port. Indications and techniques for use are described.

B TYPE: b Abstract Publication B TOPIC: b Education, Research, and Quality Improvement B PURPOSE: b To achieve appropriate and consistent oxygen prescription and delivery to patients on a respiratory ward.. B METHODS: b Medical education events about the causes of breathlessness and role of oxygen therapy were provided to doctors in training and nursing staff. Oxygen target saturation prescriptions were reviewed daily by the consultant on medication charts during the team ward rounds. The nursing staff were asked to complete an overnight oxygen report which documented the presence of a oxygen prescription, the target and actual oxygen saturation, the oxygen flow rate and any alterations made to the oxygen delivery by nurses in order to achieve the target saturation. [Extracted from the article]

The mixed layer, or epilimnion, is a physical concept referring to an isothermal layer at the surface of a water body. This concept is ubiquitous within limnology, is fundamental to our understanding of chemical and ecological processes, and is an important metric for water body monitoring, assessment and management. Despite its importance as a metric, many different approaches to approximating mixed depth currently exist. Using data from field campaigns in a small meso-eutrophic lake in the UK in 2016 and 2017 we tested whether different definitions of mixed depth resulted in comparable estimates and whether variables other than temperature could be assumed to be mixed within the layer. Different methods resulted in very different estimates for the mixed depth and ecologically important variables were not necessarily homogenously spread through the epilimnion. Furthermore, calculation of simple ecologically relevant metrics based on mixed depth showed that these metrics were highly dependent on the definition of mixed depth used. The results demonstrate that an idealised concept of a well-defined fully mixed layer is not necessarily appropriate. The widespread use of multiple definitions for mixed depth impairs the comparability of different studies while associated uncertainty over the most appropriate definition limits the confirmability of studies utilising the mixed depths. Image 1 • Different definitions of the mixed depth produce highly inconsistent estimates. • Interpretation of ecological processes can be shaped by the mixed depth definition. • Studies should assess the robustness of their findings to mixed depth definition. [ABSTRACT FROM AUTHOR]

Introduction: This paper presents a quantitative and qualitative study exploring patients' knowledge and experience of hyperbaric oxygen treatment (HBOT)., Methods: Participants included 29 patients with appropriate indications who were undertaking HBOT at facilities in two different locations: Hobart, Australia, and Plymouth, United Kingdom. Participants completed surveys prior to commencing HBOT, after five sessions, and on completion of HBOT. Semi-structured one-to-one interviews were conducted with each individual on conclusion of their course. Data were analysed using descriptive statistics and interpretive description., Results: Prior to referral, 15/29 (52%) of participants knew HBOT was used to treat divers, and of these, 9/15 (60%) were familiar with its use for non-divers. Only one third sought additional information about the process between referral for HBOT and attending their medical assessment. Anxiety was a pre-treatment concern amongst participants. However, when re-measured after five sessions and upon completion of the HBOT course, anxiety was reduced. The interview data revealed themes based around the physical, emotional and social aspects of HBOT: (1) anxiety within self; (2) naivety to normalisation; (3) enjoyment being a 'diver'; and (4) burdens of HBOT., Conclusions: Many patients experienced anxiety prior to commencing HBOT but, with support, quickly adjusted to treatment, transitioning from a state of naivety to normalisation in their experience of the hyperbaric chamber. They enjoyed feeling like a 'diver' and considered aspects of the burdens of treatment, such as finances or logistics, a minor inconvenience. These results highlight the need for psychosocial support during treatment by identifying gaps in patient preparation for HBOT., (Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.)

This article presents various studies related to the use of oxygen in lung diseases. The Royal College of Physicians guidelines for oxygen therapy included guidelines for ambulatory oxygen. However, the use of ambulatory oxygen is not universal within Great Britain. To assess its use and that of the guidelines, a questionnaire was sent to all Great Britain chest physicians. The provision of ambulatory oxygen within Great Britain is poor, with the lack of funding a major limiting factor. Current British Thoracic Society guidelines suggest that arterial blood gasses should be measured in patients with oxygen saturations of less than 93%, to guide rational use of oxygen therapy.

Background: Approximately 14% of UK hospital in-patients receive supplemental oxygen therapy, only 57% have valid prescriptions. Oxygen must be optimally prescribed to ensure maximal therapeutic response whilst minimizing adverse outcomes (including fatality). This study investigates prescription compliance., Methods: All adults admitted to medical wards (18 February to 3 March 2020) were included. Analyses present proportions, descriptive statistics, and hypothesis testing. Ethical approval was unnecessary for this audit., Results: Of the 636 patients admitted, 66 (10%) were receiving oxygen therapy. Ages ranged from 34 to 100 years with 36 (54.5%) males and 30 (45.5%) females. The prescription was not documented in the oxygen section of the drug chart (n = 37, 56.1%, p = 0.389), nor did it have the physicians signature (n = 40, 60.6%, p = 0.110) nor date (n = 46, 69.7%, p = 0.002). Thirteen chronic obstructive pulmonary disease (COPD) patients (19.7%) were at risk of hypercapnic failure (p = 1.582x10 -6 ). Target oxygen saturation (SpO2) range had been documented for 30 (45.5%) patients. A target SpO2 range of 88-92% was documented for 9 patients (13.6%), a 94-98% range documented for 11 patients (16.7%). All patients had an invalid prescription., Conclusion: We present real-world practice in naturalistic settings, immediately before pandemic-lockdown. Enhanced compliance is advocated to reduce risks of harm and mortality.

This year's Annual Review Issue of The Journal of Pathology contains 18 invited reviews on current research areas in pathology. The subject areas reflect the broad range of topics covered by the journal and this year encompass the development and application of software in digital histopathology, implementation of biomarkers in pathology practice; genetics and epigenetics, and stromal influences in disease. The reviews are authored by experts in their field and provide comprehensive updates in the chosen areas, in which there has been considerable recent progress in our understanding of disease. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd., (© 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)

Introduction: Oxygen is the most commonly administered drug to mechanically ventilated critically ill adults, yet little is known about the optimum oxygen saturation (SpO 2 ) target for these patients; the current standard of care is an SpO 2 of 96% or above. Small pilot studies have demonstrated that permissive hypoxaemia (aiming for a lower SpO 2 than normal by using a lower fractional inspired oxygen concentration (FIO 2 )) can be achieved in the critically ill and appears to be safe. This approach has not been evaluated in a National Health Service setting. It is possible that permissive hypoxaemia may be beneficial to critically ill patients thus it requires robust evaluation., Methods and Analysis: Targeted OXygen therapY in Critical illness (TOXYC) is a feasibility randomised controlled trial (RCT) to evaluate whether recruiting patients to a study of permissive hypoxaemia is possible in the UK. It will also investigate biological mechanisms that may underlie the links between oxygenation and patient outcomes. Mechanically ventilated patients with respiratory failure will be recruited from critical care units at two sites and randomised (1:1 ratio) to an SpO 2 target of either 88%-92% or ≥96% while intubated with an endotracheal tube. Clinical teams can adjust FIO 2 and ventilator settings as they wish to achieve these targets. Clinical information will be collected before, during and after the intervention and blood samples taken to measure markers of systemic oxidative stress. The primary outcome of this study is feasibility, which will be assessed by recruitment rate, protocol adherence and withdrawal rates. Secondary outcomes will include a comparison of standard critical care outcome measures between the two intervention groups, and the measurement of biomarkers of systemic oxidative stress. The results will be used to calculate a sample size, likely number of sites and overall length of time required for a subsequent large multicentre RCT., Ethics and Dissemination: This study was approved by the London - Harrow Research Ethics Committee on 2 November 2017 (REC Reference 17/LO/1334) and received HRA approval on 13 November 2017. Results from this study will be disseminated in peer-reviewed journals, at medical and scientific meetings, in the NIHR Journals Library and patient information websites., Trial Registration Number: NCT03287466; Pre-results., Competing Interests: Competing interests: DSM, MM and MPWG are directors of a company developing an oxygen delivery device (Oxygen Control Ltd). DSM has received honoraria and consultancy fees from Siemens Healthcare, Masimo, Deltex and Edwards Lifesciences. MPWG is the National Specialty Lead for Anaesthesia, Perioperative Medicine and Pain within the UK National Institute of Heath Research Clinical Research Network, an elected council member of the Royal College of Anaesthetists and serves on the board of the Evidence Based Perioperative Medicine (EBPOM) social enterprise and the medical advisory board of Sphere Medical Ltd. MPWG has received honoraria for speaking and/or travel expenses from Edwards Lifesciences, Fresenius-Kabi, BOC Medical (Linde Group), Ely-Lilly Critical Care, and Cortex GmBH. MPWG is executive chair of the Xtreme-Everest Oxygen Research Consortium and joint Editor-in-Chief of the journal Perioperative Medicine. MM is a consultant for Baxter, Edwards Lifesciences and Deltex; his University Chair is supported by Smiths Medical; Elected Council Member Royal College of Anaesthetsists; Editorial Board BJA and Critical Care; Founding Editor-in-Chief Perioperative Medicine., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)