Oral Cavity Cancers: Ethnic Differences in Radiotherapy Outcomes in a Majority South Asian Leicester Community

AIMS

Squamous cell carcinoma oral cavity cancers (SCCOCCs) have a higher reported incidence in South Asian countries. We sought to compare presenting stage and outcome by ethnicity in patients with SCCOCC treated with radical radiotherapy in a single centre in the UK.

MATERIALS AND METHODS

All patients with SCCOCC treated with radical radiotherapy at an oncology department in Leicester (UK) between 2011 and 2017 were identified. Baseline demographic, clinical data and 2-year treatment outcomes were reported.

RESULTS

Of the 109 patients included, 40 were South Asian and 59 were non-South Asian. South Asians had significantly poorer 2-year disease-free survival compared with non-South Asians (54.6% versus 73%, P = 0.01).

CONCLUSION

Our analysis suggests that South Asians with SCCOCC have poorer outcomes despite a younger age and similar disease characteristics. Environmental, social factors and differing biology of disease may be responsible and further research is required to inform targeted interventions.

Drone images afford more detections of marine wildlife than real-time observers during simultaneous large-scale surveys

There are many advantages to transitioning from conducting marine wildlife surveys via human observers onboard light-aircraft, to capturing aerial imagery using drones. However, it is important to maintain the validity of long-term data series whilst transitioning from observer to imagery surveys. We need to understand how the detection rates of target species in images compare to those collected from observers in piloted aircraft, and the factors influencing detection rates from each platform. We conducted trial ScanEagle drone surveys of dugongs in Shark Bay, Western Australia, covering the full extent of the drone's range (∼100 km), concurrently with observer surveys, with the drone flying above or just behind the piloted aircraft. We aimed to test the assumption that drone imagery could provide comparable detection rates of dugongs to human observers when influenced by same environmental conditions. Overall, the dugong sighting rate (i.e., count of individual dugongs) was 1.3 (95% CI [0.98-1.84]) times higher from the drone images than from the observers. The group sighting rate was similar for the two platforms, however the group sizes detected within the drone images were significantly larger than those recorded by the observers, which explained the overall difference in sighting rates. Cloud cover appeared to be the only covariate affecting the two platforms differently; the incidence of cloud cover resulted in smaller group sizes being detected by both platforms, but the observer group sizes dropped much more dramatically (by 71% (95% CI [31-88]) compared to no cloud) than the group sizes detected in the drone images (14% (95% CI [-28-57])). Water visibility and the Beaufort sea state also affected dugong counts and group sizes, but in the same way for both platforms. This is the first direct simultaneous comparison between sightings from observers in piloted aircraft and a drone and demonstrates the potential for drone surveys over a large spatial-scale.

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.

The development and implementation of an oxygen treatment solution for health facilities in low and middle-income countries

Background

Oxygen reduces mortality from severe pneumonia and is a vital part of case management, but achieving reliable access to oxygen is challenging in low and middle-income country (LMIC) settings. We developed and field tested two oxygen supply solutions suitable for the realities of LMIC health facilities.

Methods

A Health Needs Assessment identified a technology gap preventing reliable oxygen supplies in Gambian hospitals. We used simultaneous engineering to develop two solutions: a Mains-Power Storage (Mains-PS) system consisting of an oxygen concentrator and batteries connected to mains power, and a Solar-Power Storage (Solar-PS) system (with batteries charged by photovoltaic panels) and evaluated them in health facilities in The Gambia and Fiji to assess reliability, usability and costs.

Results

The Mains-PS system delivered the specified ≥85% (±3%) oxygen concentration in 100% of 1-2 weekly measurements over 12 months, which was available to 100% of hypoxaemic patients, and 100% of users rated ease-of-use as at least ‘good’ (90% very good or excellent). The Solar-PS system delivered ≥85% ± 3%) oxygen concentration in 100% of 1-2 weekly measurements, was available to 100% of patients needing oxygen, and 100% of users rated ease-of-use at least very good.

Costs for the systems (in US dollars) were: PS$9519, Solar-PS standard version $20 718. The of oxygen for a standardised 30-bed health facility using 1.7 million litres of oxygen per year was: for cylinders 3.2 cents (c)/L in The Gambia and 6.8 c/L in Fiji, for the PS system 1.2 c/L in both countries, and for the Solar-PS system 1.5 c/L in both countries.

Conclusions

The oxygen systems developed and tested delivered high-quality, reliable, cost-efficient oxygen in LMIC contexts, and were easy to operate. Reliable oxygen supplies are achievable in LMIC health facilities like those in The Gambia and Fiji.

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).

Oxygen systems to improve clinical care and outcomes for children and neonates: A stepped-wedge cluster-randomised trial in Nigeria

BACKGROUND

Improving oxygen systems may improve clinical outcomes for hospitalised children with acute lower respiratory infection (ALRI). This paper reports the effects of an improved oxygen system on mortality and clinical practices in 12 general, paediatric, and maternity hospitals in southwest Nigeria.

METHODS AND FINDINGS

We conducted an unblinded stepped-wedge cluster-randomised trial comparing three study periods: baseline (usual care), pulse oximetry introduction, and stepped introduction of a multifaceted oxygen system. We collected data from clinical records of all admitted neonates (<28 days old) and children (28 days to 14 years old). Primary analysis compared the full oxygen system period to the pulse oximetry period and evaluated odds of death for children, children with ALRI, neonates, and preterm neonates using mixed-effects logistic regression. Secondary analyses included the baseline period (enabling evaluation of pulse oximetry introduction) and evaluated mortality and practice outcomes on additional subgroups. Three hospitals received the oxygen system intervention at 4-month intervals. Primary analysis included 7,716 neonates and 17,143 children admitted during the 2-year stepped crossover period (November 2015 to October 2017). Compared to the pulse oximetry period, the full oxygen system had no association with death for children (adjusted odds ratio [aOR] 1.06; 95% confidence interval [CI] 0.77-1.46; p = 0.721) or children with ALRI (aOR 1.09; 95% CI 0.50-2.41; p = 0.824) and was associated with an increased risk of death for neonates overall (aOR 1.45; 95% CI 1.04-2.00; p = 0.026) but not preterm/low-birth-weight neonates (aOR 1.30; 95% CI 0.76-2.23; p = 0.366). Secondary analyses suggested that the introduction of pulse oximetry improved oxygen practices prior to implementation of the full oxygen system and was associated with lower odds of death for children with ALRI (aOR 0.33; 95% CI 0.12-0.92; p = 0.035) but not for children, preterm neonates, or neonates overall (aOR 0.97, 95% CI 0.60-1.58, p = 0.913; aOR 1.12, 95% CI 0.56-2.26, p = 0.762; aOR 0.90, 95% CI 0.57-1.43, p = 0.651). Limitations of our study are a lower-than-anticipated power to detect change in mortality outcomes (low event rates, low participant numbers, high intracluster correlation) and major contextual changes related to the 2016-2017 Nigerian economic recession that influenced care-seeking and hospital function during the study period, potentially confounding mortality outcomes.

CONCLUSIONS

We observed no mortality benefit for children and a possible higher risk of neonatal death following the introduction of a multifaceted oxygen system compared to introducing pulse oximetry alone. Where some oxygen is available, pulse oximetry may improve oxygen usage and clinical outcomes for children with ALRI.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12617000341325.

Hypoxaemia in hospitalised children and neonates: A prospective cohort study in Nigerian secondary-level hospitals

BACKGROUND

Hypoxaemia is a common complication of pneumonia and a major risk factor for death, but less is known about hypoxaemia in other common conditions. We evaluated the epidemiology of hypoxaemia and oxygen use in hospitalised neonates and children in Nigeria.

METHODS

We conducted a prospective cohort study among neonates and children (<15 years of age) admitted to 12 secondary-level hospitals in southwest Nigeria (November 2015-November 2017) using data extracted from clinical records (documented during routine care). We report summary statistics on hypoxaemia prevalence, oxygen use, and clinical predictors of hypoxaemia. We used generalised linear mixed-models to calculate relative odds of death (hypoxaemia vs not).

FINDINGS

Participating hospitals admitted 23,926 neonates and children during the study period. Pooled hypoxaemia prevalence was 22.2% (95%CI 21.2-23.2) for neonates and 10.2% (9.7-10.8) for children. Hypoxaemia was common among children with acute lower respiratory infection (28.0%), asthma (20.4%), meningitis/encephalitis (17.4%), malnutrition (16.3%), acute febrile encephalopathy (15.4%), sepsis (8.7%) and malaria (8.5%), and neonates with neonatal encephalopathy (33.4%), prematurity (26.6%), and sepsis (21.0%). Hypoxaemia increased the adjusted odds of death 6-fold in neonates and 7-fold in children. Clinical signs predicted hypoxaemia poorly, and their predictive ability varied across ages and conditions. Hypoxaemic children received oxygen for a median of 2-3 days, consuming ∼3500 L of oxygen per admission.

INTERPRETATION

Hypoxaemia is common in respiratory and non-respiratory acute childhood illness and increases the risk of death substantially. Given the limitations of clinical signs, pulse oximetry is an essential tool for detecting hypoxaemia, and should be part of the routine assessment of all hospitalised neonates and children.

Comparisons between the ON- and OFF-edge motion pathways in the Drosophila brain

Understanding the circuit mechanisms behind motion detection is a long-standing question in visual neuroscience. In Drosophila melanogaster, recently discovered synapse-level connectomes in the optic lobe, particularly in ON-pathway (T4) receptive-field circuits, in concert with physiological studies, suggest a motion model that is increasingly intricate when compared with the ubiquitous Hassenstein-Reichardt model. By contrast, our knowledge of OFF-pathway (T5) has been incomplete. Here, we present a conclusive and comprehensive connectome that, for the first time, integrates detailed connectivity information for inputs to both the T4 and T5 pathways in a single EM dataset covering the entire optic lobe. With novel reconstruction methods using automated synapse prediction suited to such a large connectome, we successfully corroborate previous findings in the T4 pathway and comprehensively identify inputs and receptive fields for T5. Although the two pathways are probably evolutionarily linked and exhibit many similarities, we uncover interesting differences and interactions that may underlie their distinct functional properties.

An evaluation of the error and uncertainty in epibenthos cover estimates from AUV images collected with an efficient, spatially-balanced design

Efficient monitoring of organisms is at the foundation of protected area and biodiversity management. Such monitoring programs are based on a systematically selected set of survey locations that, while able to track trends at those locations through time, lack inference for the overall region being "monitored". Advances in spatially-balanced sampling approaches offer alternatives but remain largely untested in marine ecosystems. This study evaluated the merit of using a two-stage, spatially-balanced survey framework, in conjunction with generalized additive models, to estimate epifauna cover at a reef-wide scale for mesophotic reefs within a large, cross-shelf marine park. Imagery acquired by an autonomous underwater vehicle was classified using a hierarchical scheme developed under the Collaborative and Automated Tools for Analysis of Marine Imagery (CATAMI). At a realistic image subsampling intensity, the two-stage, spatially-balanced framework provided accurate and precise estimates of reef-wide cover for a select number of epifaunal classes at the coarsest CATAMI levels, in particular bryozoan and porifera classes. However, at finer hierarchical levels, accuracy and/or precision of cover estimates declined, primarily because of the natural rarity of even the most common of these classes/morphospecies. Ranked predictor importance suggested that bathymetry, backscatter and derivative terrain variables calculated at their smallest analysis window scales (i.e. 81 m2) were generally the most important variables in the modeling of reef-wide cover. This study makes an important step in identifying the constraints and limitations that can be identified through a robust statistical approach to design and analysis. The two-stage, spatially-balanced framework has great potential for effective quantification of epifaunal cover in cross-shelf mesophotic reefs. However, greater image subsampling intensity than traditionally applied is required to ensure adequate observations for finer-level CATAMI classes and associated morphospecies.

Detecting suspicious activities at sea based on anomalies in Automatic Identification Systems transmissions

Automatic Identification Systems (AIS) are a standard feature of ocean-going vessels, designed to allow vessels to notify each other of their position and route, to reduce collisions. Increasingly, the system is being used to monitor vessels remotely, particularly with the advent of satellite receivers. One fundamental problem with AIS transmission is the issue of gaps in transmissions. Gaps occur for three basic reasons: 1) saturation of the system in locations with high vessel density; 2) poor quality transmissions due to equipment on the vessel or receiver; and 3) intentional disabling of AIS transmitters. Resolving which of these mechanisms is responsible for generating gaps in transmissions from a given vessel is a critical task in using AIS to remotely monitor vessels. Moreover, separating saturation and equipment issues from intentional disabling is a key issue, as intentional disabling is a useful risk factor in predicting illicit behaviors such as illegal fishing. We describe a spatial statistical model developed to identify gaps in AIS transmission, which allows calculation of the probability that a given gap is due to intentional disabling. The model we developed successfully identifies high risk gaps in the test case example in the Arafura Sea. Simulations support that the model is sensitive to frequent gaps as short as one hour. Results in this case study area indicate expected high risk vessels were ranked highly for risk of intentional disabling of AIS transmitters. We discuss our findings in the context of improving enforcement opportunities to reduce illicit activities at sea.

Loitering with intent-Catching the outlier vessels at sea

Illegal, Unreported and Unregulated (IUU) fishing activities pose one of the most significant threats to sustainable fisheries worldwide. Identifying illegal behaviour, specifically fishing and at-sea transhipment, continues to be a fundamental hurdle in combating IUU fishing. Here, we explore the use of spatial statistical methods to identify vessels behaving anomalously, in particular with regard to loitering, using the Indonesian Exclusive Economic Zone (EEZ) and surrounding waters as a case-study. Using Automatic Identification System (AIS) for vessel tracking, we applied Generalized Additive Models to capture both the temporal and spatial nature of loitering behaviour. We identified three statistically anomalous loitering behaviours (based on time, speed and distance) and applied the models to 2700 vessels in the region. We were able to rank vessels for individual and joint probability of atypical behaviour, providing a hierarchical list of vessels engaging in anomalous behaviour. While identification of irregular behaviour does not mean vessels are definitely engaging in illegal activities, this statistical modelling approach can be used to prioritise the allocation of enforcement resources and assist authorities under the United Nations Food and Agricultural Organization Port State Measures Agreement for management and enforcement of IUU fishing associated activities.

Implementation and 8-year follow-up of an uninterrupted oxygen supply system in a hospital in The Gambia

SETTING: A 42-bed hospital operated by the Medical Research Council (MRC) Unit in The Gambia.

OBJECTIVE: To devise, test and evaluate a cost-efficient uninterrupted oxygen system in the MRC Hospital.

DESIGN: Oxygen cylinders were replaced with oxygen concentrators as the primary source of oxygen. An uninterruptable power supply (UPS) ensured continuity of power. Hospital staff were trained on the use of the new system. Eight years post-installation, an analysis of concentrator maintenance needs and costs was conducted and user feedback obtained to assess the success of the system.

RESULTS: The new system saved at least 51% of oxygen supply costs compared to cylinders, with savings likely to have been far greater due to cylinder leakages. Users indicated that the system is easier to use and more reliable, although technical support and staff training are still needed.

CONCLUSION: Oxygen concentrators offer long-term cost savings and an improved user experience compared to cylinders; however, some technical support and maintenance are needed to upkeep the system. A UPS dedicated to oxygen concentrators is an appropriate solution for settings where power interruptions are frequent but short in duration. This approach can be a model for health systems in settings with similar infrastructure.

Improving oxygen therapy for children and neonates in secondary hospitals in Nigeria: study protocol for a stepped-wedge cluster randomised trial

BACKGROUND

Oxygen is a life-saving, essential medicine that is important for the treatment of many common childhood conditions. Improved oxygen systems can reduce childhood pneumonia mortality substantially. However, providing oxygen to children is challenging, especially in small hospitals with weak infrastructure and low human resource capacity.

METHODS/DESIGN

This trial will evaluate the implementation of improved oxygen systems at secondary-level hospitals in southwest Nigeria. The improved oxygen system includes: a standardised equipment package; training of clinical and technical staff; infrastructure support (including improved power supply); and quality improvement activities such as supportive supervision. Phase 1 will involve the introduction of pulse oximetry alone; phase 2 will involve the introduction of the full, improved oxygen system package. We have based the intervention design on a theory-based analysis of previous oxygen projects, and used quality improvement principles, evidence-based teaching methods, and behaviour-change strategies. We are using a stepped-wedge cluster randomised design with participating hospitals randomised to receive an improved oxygen system at 4-month steps (three hospitals per step). Our mixed-methods evaluation will evaluate effectiveness, impact, sustainability, process and fidelity. Our primary outcome measures are childhood pneumonia case fatality rate and inpatient neonatal mortality rate. Secondary outcome measures include a range of clinical, quality of care, technical, and health systems outcomes. The planned study duration is from 2015 to 2018.

DISCUSSION

Our study will provide quality evidence on the effectiveness of improved oxygen systems, and how to better implement and scale-up oxygen systems in resource-limited settings. Our results should have important implications for policy-makers, hospital administrators, and child health organisations in Africa and globally.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12617000341325 . Retrospectively registered on 6 March 2017.

Unmanned aerial vehicles for surveying marine fauna: assessing detection probability

Aerial surveys are conducted for various fauna to assess abundance, distribution, and habitat use over large spatial scales. They are traditionally conducted using light aircraft with observers recording sightings in real time. Unmanned Aerial Vehicles (UAVs) offer an alternative with many potential advantages, including eliminating human risk. To be effective, this emerging platform needs to provide detection rates of animals comparable to traditional methods. UAVs can also acquire new types of information, and this new data requires a reevaluation of traditional analyses used in aerial surveys; including estimating the probability of detecting animals. We conducted 17 replicate UAV surveys of humpback whales (Megaptera novaeangliae) while simultaneously obtaining a 'census' of the population from land-based observations, to assess UAV detection probability. The ScanEagle UAV, carrying a digital SLR camera, continuously captured images (with 75% overlap) along transects covering the visual range of land-based observers. We also used ScanEagle to conduct focal follows of whale pods (n = 12, mean duration = 40 min), to assess a new method of estimating availability. A comparison of the whale detections from the UAV to the land-based census provided an estimated UAV detection probability of 0.33 (CV = 0.25; incorporating both availability and perception biases), which was not affected by environmental covariates (Beaufort sea state, glare, and cloud cover). According to our focal follows, the mean availability was 0.63 (CV = 0.37), with pods including mother/calf pairs having a higher availability (0.86, CV = 0.20) than those without (0.59, CV = 0.38). The follows also revealed (and provided a potential correction for) a downward bias in group size estimates from the UAV surveys, which resulted from asynchronous diving within whale pods, and a relatively short observation window of 9 s. We have shown that UAVs are an effective alternative to traditional methods, providing a detection probability that is within the range of previous studies for our target species. We also describe a method of assessing availability bias that represents spatial and temporal characteristics of a survey, from the same perspective as the survey platform, is benign, and provides additional data on animal behavior.

Providing oxygen to children in hospitals: a realist review

OBJECTIVE

To identify and describe interventions to improve oxygen therapy in hospitals in low-resource settings, and to determine the factors that contribute to success and failure in different contexts.

METHODS

Using realist review methods, we scanned the literature and contacted experts in the field to identify possible mechanistic theories of how interventions to improve oxygen therapy systems might work. Then we systematically searched online databases for evaluations of improved oxygen systems in hospitals in low- or middle-income countries. We extracted data on the effectiveness, processes and underlying theory of selected projects, and used these data to test the candidate theories and identify the features of successful projects.

FINDINGS

We included 20 improved oxygen therapy projects (45 papers) from 15 countries. These used various approaches to improving oxygen therapy, and reported clinical, quality of care and technical outcomes. Four effectiveness studies demonstrated positive clinical outcomes for childhood pneumonia, with large variation between programmes and hospitals. We identified factors that help or hinder success, and proposed a practical framework depicting the key requirements for hospitals to effectively provide oxygen therapy to children. To improve clinical outcomes, oxygen improvement programmes must achieve good access to oxygen and good use of oxygen, which should be facilitated by a broad quality improvement capacity, by a strong managerial and policy support and multidisciplinary teamwork.

CONCLUSION

Our findings can inform practitioners and policy-makers about how to improve oxygen therapy in low-resource settings, and may be relevant for other interventions involving the introduction of health technologies.

Improved oxygen systems in district hospitals in Lao PDR: a prospective field trial of the impact on outcomes for childhood pneumonia and equipment sustainability

BACKGROUND

Hypoxaemia is a common and potentially fatal complication of many childhood, newborn and maternal conditions but often not well recognised or managed in settings where resources are limited. Oxygen itself is often inaccessible due to cost or logistics. This paper describes implementation of oxygen systems in Lao district hospitals, clinical outcomes after 24 months and equipment outcomes after 40 months postimplementation.

METHODS

A prospective field trial was conducted in 20 district hospitals, including 10 intervention hospitals that received oxygen concentrators and 10 control hospitals. Equipment outcomes were evaluated at baseline, 12, 24 and 40 months. Clinical outcomes of children under 5 years of age with pneumonia were evaluated using a before-and-after controlled study design with information retrospectively collected from medical records.

RESULTS

Fourteen (37%), 7 (18%) and 12 (34%) of 38 concentrators required repair at 12, 24 and 40 months, respectively. The proportion of children discharged well increased in intervention (90% (641/712) to 95.2% (658/691)) and control hospitals (87.1% (621/713) to 92.1% (588/606)). In intervention hospitals, case fatality rates for childhood pneumonia fell from 2.7% (19/712) preintervention to 0.80% (6/691) postintervention with no change in control hospitals (1.7% (12/713) preintervention and 2.3% (14/606) postintervention).

CONCLUSION

Medium-term sustainability of oxygen concentrators in hospitals accompanied by reduced case fatality for childhood pneumonia has been demonstrated in Lao PDR. Significant local engineering capacity to address multiple causes of equipment malfunction was critical. The ongoing requirements and fragile structures within the health system remain major risks to long-term sustainability.

Oxygen for children and newborns in non-tertiary hospitals in South-west Nigeria: A needs assessment

BACKGROUND

Oxygen is important for the treatment of hypoxaemia associated with pneumonia, malaria, and other medical, obstetric, and surgical conditions. Access to oxygen therapy is limited in many of the high mortality settings where it would be of most benefit.

METHODS

A needs assessment of 12 non-tertiary hospitals in south-west Nigeria, assessing structural, technical and clinical barriers to the provision of safe and effective oxygen therapy.

RESULTS

Oxygen supply was reported to be a major challenge by hospital directors. All hospitals had some access to oxygen cylinders, which were expensive and frequently ran out. Nine (75%) hospitals used oxygen concentrators, which were limited by inadequate power supply and lack of maintenance capacity. Appropriate oxygen delivery and monitoring devices (nasal prongs, catheters, pulse oximeters) were poorly available, and no hospitals had clinical guidelines pertaining to the use of -oxygen for children. Oxygen was expensive to patients (median US$20/day) and to hospitals. Estimated oxygen demand is reported using both a constant mean-based estimate and adjustment for seasonal and other variability.

CONCLUSIONS

Making oxygen available to sick children and neonates in Nigerian hospitals will require: improving detection of hypoxaemia through routine use of pulse oximetry; improving access to oxygen through equipment, training, and maintenance structures; and commitment to building hospital and state structures that can sustain and expand oxygen initiatives.

Designing an effective mark-recapture study of Antarctic blue whales

To properly conserve and manage wild populations, it is important to have information on abundance and population dynamics. In the case of rare and cryptic species, especially in remote locations, surveys can be difficult and expensive, and run the risk of not producing sample sizes large enough to produce precise estimates. Therefore, it is crucial to conduct preliminary analysis to determine if the study will produce useable estimates. The focus of this paper is a proposed mark-recapture study of Antarctic blue whales (Balaenoptera musculus intermedia). Antarctic blue whales were hunted to near extinction up until the mid- 1960s, when commercial exploitation of this species ended. Current abundance estimates are a decade old. Furthermore, at present, there are no formal circumpolar-level cetacean surveys operating in Antarctic waters and, specifically, there is no strategy to monitor the potential recovery of Antarctic blue whales. Hence the work in this paper was motivated by the need to inform decisions on strategies for future monitoring of Antarctic blue whale population. The paper describes a model to predict the precision and bias of estimates from a proposed survey program. The analysis showed that mark-recapture is indeed a suitable method to provide a circumpolar abundance estimate of Antarctic blue whales, with precision of the abundance, at the midpoint of the program, predicted to be between 0.2 and 0.3. However, this was only if passive acoustic tracking was utilized to increase the encounter rate. The analysis also provided guidance on general design for an Antarctic blue whale program, showing that it requires a 12-year duration; although surveys do not necessarily need to be run every year if multiple vessels are available to clump effort. Mark-recapture is based on a number of assumptions; it was evident from the analysis that ongoing analysis and monitoring of the data would be required to check such assumptions hold (e.g., test for heterogeneity), with the modeling adjusted as needed.

Understanding the sources and effects of abandoned, lost, and discarded fishing gear on marine turtles in northern Australia

Globally, 6.4 million tons of fishing gear are lost in the oceans annually. This gear (i.e., ghost nets), whether accidently lost, abandoned, or deliberately discarded, threatens marine wildlife as it drifts with prevailing currents and continues to entangle marine organisms indiscriminately. Northern Australia has some of the highest densities of ghost nets in the world, with up to 3 tons washing ashore per kilometer of shoreline annually. This region supports globally significant populations of internationally threatened marine fauna, including 6 of the 7 extant marine turtles. We examined the threat ghost nets pose to marine turtles and assessed whether nets associated with particular fisheries are linked with turtle entanglement by analyzing the capture rates of turtles and potential source fisheries from nearly 9000 nets found on Australia's northern coast. Nets with relatively larger mesh and smaller twine sizes (e.g., pelagic drift nets) had the highest probability of entanglement for marine turtles. Net size was important; larger nets appeared to attract turtles, which further increased their catch rates. Our results point to issues with trawl and drift-net fisheries, the former due to the large number of nets and fragments found and the latter due to the very high catch rates resulting from the net design. Catch rates for fine-mesh gill nets can reach as high as 4 turtles/100 m of net length. We estimated that the total number of turtles caught by the 8690 ghost nets we sampled was between 4866 and 14,600, assuming nets drift for 1 year. Ghost nets continue to accumulate on Australia's northern shore due to both legal and illegal fishing; over 13,000 nets have been removed since 2005. This is an important and ongoing transboundary threat to biodiversity in the region that requires attention from the countries surrounding the Arafura and Timor Seas.

A simulation study of acoustic-assisted tracking of whales for mark-recapture surveys

Collecting enough data to obtain reasonable abundance estimates of whales is often difficult, particularly when studying rare species. Passive acoustics can be used to detect whale sounds and are increasingly used to estimate whale abundance. Much of the existing effort centres on the use of acoustics to estimate abundance directly, e.g. analysing detections in a distance sampling framework. Here, we focus on acoustics as a tool incorporated within mark-recapture surveys. In this context, acoustic tools are used to detect and track whales, which are then photographed or biopsied to provide data for mark-recapture analyses. The purpose of incorporating acoustics is to increase the encounter rate beyond using visual searching only. While this general approach is not new, its utility is rarely quantified. This paper predicts the “acoustically-assisted” encounter rate using a discrete-time individual-based simulation of whales and survey vessel. We validate the simulation framework using existing data from studies of sperm whales. We then use the framework to predict potential encounter rates in a study of Antarctic blue whales. We also investigate the effects of a number of the key parameters on encounter rate. Mean encounter rates from the simulation of sperm whales matched well with empirical data. Variance of encounter rate, however, was underestimated. The simulation of Antarctic blue whales found that passive acoustics should provide a 1.7–3.0 fold increase in encounter rate over visual-only methods. Encounter rate was most sensitive to acoustic detection range, followed by vocalisation rate. During survey planning and design, some indication of the relationship between expected sample size and effort is paramount; this simulation framework can be used to predict encounter rates and establish this relationship. For a case in point, the simulation framework indicates unequivocally that real-time acoustic tracking should be considered for quantifying the abundance of Antarctic blue whales via mark-recapture methods.

Indications and outcomes for 100 patients managed with a pectoralis major flap within a UK maxillofacial unit

There are few studies reporting the role of the pedicled pectoralis major (PPM) flap in modern maxillofacial practice. The outcomes of 100 patients (102 flaps) managed between 1996 and 2012 in a UK maxillofacial unit that preferentially practices free tissue reconstruction are reported. The majority (88.2%) of PPM flaps were for oral squamous cell carcinoma (SCC), stage IV (75.6%) disease, and there was substantial co-morbidity (47.0% American Society of Anesthesiologists 3 or 4). The PPM flap was the preferred reconstruction on 80.4% of occasions; 19.6% followed free flap failure. Over half of the patients (57%) had previously undergone major surgery and/or chemoradiotherapy. Ischaemic heart disease (P=0.028), diabetes mellitus (P=0.040), and methicillin-resistant Staphylococcus aureus (MRSA) infection (P=0.013) were independently associated with flap loss (any degree). Free flap failure was independently associated with total (2.0%) and major (6.9%) partial flap loss (P=0.044). Cancer-specific 5-year survival for stage IV primary SCC and salvage surgery improved in the second half (2005-2012) of the study period (22.2% vs. 79.8%, P=0.002, and 0% vs. 55.7%, P=0.064, respectively). There were also declines in recurrent disease (P=0.008), MRSA (P<0.001), and duration of admission (P=0.014). The PPM flap retains a valuable role in the management of advanced disease combined with substantial co-morbidity, and following free flap failure.

Evaluation of oxygen concentrators for use in countries with limited resources

Seven different models of oxygen concentrators were purchased. The manufacturer's data were evaluated by a ranking method for operation at high temperature and high relative humidity, power consumption, warranty and cost. Measurements were then made of the oxygen concentration produced at maximum operating temperature. All the concentrators were CE marked and claimed compliance with the relevant Standard ISO 8359:1996. Only two models complied with their specification. On examination of the concentrators and the accompanying documents we found that compliance with 61 points listed in ISO 8359 ranged from 85% to 98%. Oxygen concentration was measured with the machines running simultaneously under both high temperature and high humidity. All models delivered low oxygen concentrations at 40 °C and 95% relative humidity. Only two models delivered >82% at 35 °C and 50% relative humidity. Concentrators intended for use in countries with limited resources should be evaluated before they are purchased, by independent experts, using the methods described herein.

The functioning of oxygen concentrators in resource-limited settings: a situation assessment in two countries

SETTING

The paediatric wards of hospitals in Malawi and Mongolia.

OBJECTIVE

To describe oxygen concentrator functioning in two countries with widespread, long-term use of concentrators as a primary source of oxygen for treating children.

DESIGN

A systematic assessment of concentrators in the paediatric wards of 15 hospitals in Malawi and nine hospitals in Mongolia.

RESULTS

Oxygen concentrators had been installed for a median of 48 months (interquartile range [IQR] 6-60) and 36 months (IQR 12-96), respectively, prior to the evaluation in Malawi and Mongolia. Concentrators were the primary source of oxygen. Three quarters of the concentrators assessed in Malawi (28/36) and half those assessed in Mongolia (13/25) were functional. Concentrators were found to remain functional with up to 30 000 h of use. However, several concentrators were functioning very poorly despite limited use. Concentrators from a number of different manufacturers were evaluated, and there was marked variation in performance between brands. Inadequate resources for maintenance were reported in both countries.

CONCLUSION

Years after installation of oxygen concentrators, many machines were still functioning, indicating that widespread use can be sustained in resource-limited settings. However, concentrator performance varied substantially. Procurement of high-quality and appropriate equipment is critical, and resources should be made available for ongoing maintenance.

Late-onset bowel dysfunction after pelvic radiotherapy: a national survey of current practice and opinions of clinical oncologists

AIMS

Seventeen thousand patients receive treatment with radical pelvic radiotherapy annually in the UK. It is common for patients to develop gastrointestinal symptoms after treatment. The aim of this study was to determine the current practice of clinical oncologists in the UK with respect to late-onset bowel dysfunction after pelvic radiotherapy, and to discuss the wider issues surrounding current and future service provision for this patient group.

MATERIALS AND METHODS

A questionnaire was developed to establish current practice. This was sent to the 314 clinical oncologists in the UK who treat pelvic malignancies up to a maximum of three times.

RESULTS

One hundred and ninety (61%) responses were received. Most oncologists (76%) screen for gastrointestinal dysfunction after pelvic radiotherapy, usually through history taking rather than formal tools. Clinical oncologists view toxicity as a significant problem, with most estimating that up to 24% of patients at 1 year have bowel symptoms. Most oncologists refer less than 50% of their symptomatic patients, with most referring less than 10%. These referrals are 31% to a gastroenterologist, 23% to a gastrointestinal surgeon and 33% to both. Most (58%) do not have access to a gastroenterologist or a gastrointestinal surgeon with a specialist interest in their area. Sixty-five per cent of oncologists think a service is required specifically for patients with bowel dysfunction after pelvic radiotherapy, but half (52%) think that the current service in their area is inadequate.

CONCLUSIONS

Clinical oncologists recognise late-onset bowel dysfunction after pelvic radiotherapy as a significant problem, but one that is linked to poor recognition of symptoms and an inadequate patchy service.

Meeting oxygen needs in Africa: an options analysis from the Gambia

OBJECTIVE

To compare oxygen supply options for health facilities in the Gambia and develop a decision-making algorithm for choosing oxygen delivery systems in Africa and the rest of the developing world.

METHODS

Oxygen cylinders and concentrators were compared in terms of functionality and cost. Interviews with key informants using locally developed and adapted WHO instruments, operational assessments, cost-modelling and cost measurements were undertaken to determine whether oxygen cylinders or concentrators were the better choice. An algorithm and a software tool to guide the choice of oxygen delivery system were constructed.

FINDINGS

In the Gambia, oxygen concentrators have significant advantages compared to cylinders where power is reliable; in other settings, cylinders are preferable as long as transporting them is feasible. Cylinder costs are greatly influenced by leakage, which is common, whereas concentrator costs are affected by the cost of power far more than by capital costs. Only two of 12 facilities in the Gambia were found suitable for concentrators; at the remaining 10 facilities, cylinders were the better option.

CONCLUSION

Neither concentrators nor cylinders are well suited to every situation, but a simple options assessment can determine which is better in each setting. Nationally this would result in improved supply and lower costs by comparison with conventional cylinders alone, although ensuring a reliable supply would remain a challenge. The decision algorithm and software tool designed for the Gambia could be applied in other developing countries.

Oxygen is an essential medicine: a call for international action

Hypoxaemia is commonly associated with mortality in developing countries, yet feasible and cost-effective ways to address hypoxaemia receive little or no attention in current global health strategies. Oxygen treatment has been used in medicine for almost 100 years, but in developing countries most seriously ill newborns, children and adults do not have access to oxygen or the simple test that can detect hypoxaemia. Improving access to oxygen and pulse oximetry has demonstrated a reduction in mortality from childhood pneumonia by up to 35% in high-burden child pneumonia settings. The cost-effectiveness of an oxygen systems strategy compares favourably with other higher profile child survival interventions, such as new vaccines. In addition to its use in treating acute respiratory illness, oxygen treatment is required for the optimal management of many other conditions in adults and children, and is essential for safe surgery, anaesthesia and obstetric care. Oxygen concentrators provide the most consistent and least expensive source of oxygen in health facilities where power supplies are reliable. Oxygen concentrators are sustainable in developing country settings if a systematic approach involving nurses, doctors, technicians and administrators is adopted. Improving oxygen systems is an entry point for improving the quality of care. For these broad reasons, and for its vital importance in reducing deaths due to lung disease in 2010: Year of the Lung, oxygen deserves a higher priority on the global health agenda.

Oxygen supplies for hospitals in Papua New Guinea: a comparison of the feasibility and cost-effectiveness of methods for different settings

Oxygen therapy is essential in all wards, emergency departments and operating theatres of hospitals at all levels, and oxygen is life-saving. In Papua New Guinea (PNG), an effective oxygen system that improved the detection and treatment of hypoxaemia in provincial and district hospitals reduced death rates from pneumonia in children by as much as 35%. The methods for providing oxygen in PNG are reviewed. A busy provincial hospital will use on average about 38,000 l of oxygen each day. Over 2 years the cost of this amount of oxygen being provided by cylinders (at least K555,000) or an oxygen generator (about K1 million) is significantly more than the cost of setting up and maintaining a comprehensive system of bedside oxygen concentrators (K223,000). A district hospital will use 17,000 l per day. The full costs of this over 2 years are K33,000 if supplied by bedside concentrators, or K333,000 plus transport costs if the oxygen source is cylinders. In provincial and district hospitals bedside oxygen concentrators will be the most cost-effective, simple and reliable sources of oxygen. In large hospitals where there are existing oxygen pipelines, or in newly designed hospitals, an oxygen generator will be effective but currently much more expensive than bedside concentrators that provide the same volume of oxygen generation. There are options for oxygen concentrator use in hospitals and health centres that do not have reliable power. These include battery storage of power or solar power. While these considerably add to the establishment cost when changing from cylinders to concentrators, a battery-powered system should repay its capital costs in less than one year, though this has not yet been proven in the field. Bedside oxygen concentrators are currently the 'best-buy' in supplying oxygen in most hospitals in PNG, where cylinder oxygen is the largest single item in their drug budget. Oxygen concentrators should not be seen as an expensive intervention that has to rely on donor support, but as a cost-saving intervention for all hospitals.

Enhanced Expression of Radiation-induced Leukocyte CDKN1A mRNA in Multiple Primary Breast Cancer Patients: Potential New Marker of Cancer Susceptibility

This study was designed to discover blood biomarkers of cancer susceptibility using invasive multiple (n = 21), single primary breast cancer (n = 21), and control subjects (n = 20). Heparinized whole blood was incubated at 37 °C for 2 hours after 0–10 Gy of radiation, then cell cycle arrest marker CDKN1A and apoptosis marker BBC3 mRNA were quantified. This epidemiological study was practically feasible because radiation-induced mRNA was preserved for at least 1 day whenever blood was stored at 4 °C (r² = 0.901). Moreover, blood could be stored frozen after radiation treatment (r² = 0.797). Radiation-induced CDKN1A and BBC3 mRNA were dose dependent, and the degree of induction of CDKN1A was correlated with that of BBC3 (r² = 0.679). Interestingly, multiple primary cases showed higher induction of CDKN1A mRNA than single primary and control groups, whereas BBC3 did not show such differences. The results suggested that cancer susceptibility represented by the multiple primary breast cancer cases was related to over-reaction of CDKN1A mRNA, not BBC3. The study also suggests that ex vivo gene expression analysis could potentially be used as a new tool in epidemiological studies for cancer and radiation sensitivity research.

Oxygen for treatment of severe pneumonia in The Gambia, West Africa: a situational analysis

SETTING

Health facilities in The Gambia, West Africa.

OBJECTIVES

Oxygen treatment is vital in pneumonia, the leading cause of death in children globally. There are shortages of oxygen in developing countries, but little information is available on the extent of the problem. We assessed national oxygen availability and use in The Gambia, a sub-Saharan African country.

METHODS

A government-led team visited 12 health facilities in The Gambia. A modified World Health Organization assessment tool was used to determine oxygen requirements, current provision and capacity to support effective oxygen use.

RESULTS

Eleven of the 12 facilities managed severe pneumonia. Oxygen was reliable in three facilities. Requirement and supply were often mismatched. Both oxygen concentrators and oxygen cylinders were used. Suboptimal electricity and maintenance made using concentrators difficult, while logistical problems and cost hampered cylinder use. Children were usually triaged by trained nurses who reported lack of training in oxygen use. Oxygen was given typically by nasal prongs; pulse oximetry was available in two facilities.

CONCLUSIONS

National data showed that oxygen availability did not meet needs in most Gambian health facilities. Remedial options must be carefully assessed for real costs, reliability and site-by-site usability. Training is needed to support oxygen use and equipment maintenance.

Improved oxygen systems for childhood pneumonia: a multihospital effectiveness study in Papua New Guinea

BACKGROUND

In rural hospitals of developing countries, oxygen supplies are poor and detection of hypoxaemia is difficult. Oxygen concentrators and pulse oximeters might help to manage the disease; however, use of such technology in developing countries needs comprehensive assessment. We studied the effect of an improved oxygen system on death rate in children with pneumonia in Papua New Guinea.

METHODS

We installed an improved oxygen system in five hospitals in Papua New Guinea, and assessed its use in more than 11 000 children with pneumonia (2001-07) and compared case-fatality rates. Admissions between January, 2001, and December, 2004, formed the pre-intervention group, and those between July, 2005, and October, 2007, formed the post-intervention group. Oxygen concentrators and pulse oximeters were introduced in the five hospitals, and a protocol for detection of hypoxaemia and clinical use of oxygen was supplied. All children admitted had their oxygen saturation measured; if it was less than 90%, oxygen was delivered via nasal prongs at a starting flow rate of 0.5-1 L/min. We recorded all costs associated with the establishment and maintenance of this system. The study was approved by the Medical Research Advisory Committee of Papua New Guinea, number MRAC 04.02.

FINDINGS

Before the use of this system, 356 of 7161 children admitted in the five hospitals for pneumonia died (case-fatality rate 4.97% [95% CI 4.5-5.5]), whereas 133 of 4130 children died in the 27 months after the introduction of the system (3.22% [2.7-3.8]). After the improved system was introduced, the risk of death for a child with pneumonia was 35% lower than was that before the project began (risk ratio 0.65 [0.52-0.78], p<0.0001). Mortality rates varied between hospitals. The estimated costs of this system were US$51 per patient treated, US$1673 per life saved, and US$50 per disability-adjusted life-year (DALY) averted.

INTERPRETATION

Pulse oximetry and oxygen concentrators can alleviate oxygen shortages, reduce mortality, and improve quality of care for children with pneumonia in developing countries. The cost-effectiveness of this system compared favourably with that of other public-health interventions.

FUNDING

The Papua New Guinea National Department of Health; WHO, Papua New Guinea and Western Pacific Regional Office; AirSep corporation, Buffalo, NY, USA; the Ross Trust, VIC, Australia; AusAID; Jacques Gostelli, Switzerland; and a grant from the University of Melbourne.

Implementing an oxygen programme in hospitals in Papua New Guinea

In Papua New Guinea (PNG), the most common cause of death among children under 5 years of age is pneumonia. Children with severe pneumonia need antibiotics and oxygen but oxygen shortages are common owing to the cost and complex logistics of transporting it in cylinders. Detection of hypoxaemia using clinical signs can be difficult, especially in highly pigmented children in whom cyanosis is difficult to recognise. Pulse oximetry is the most reliable, non-invasive way of detecting hypoxaemia. However, most hospitals in PNG do not have pulse oximetry. We proposed that the installation of a reliable, sufficient and cheap supply of oxygen in hospitals coupled with the use of pulse oximetry would make a significant difference to child survival rates in PNG. Oxygen concentrators, which extract oxygen from ambient air, were installed in the children's wards of five hospitals during 2005. Pulse oximeters were also introduced to enable better detection of hypoxaemia. This paper describes the technical aspects of this programme: the equipment used and the rationale behind choosing it, the installation, commissioning and testing processes. The ongoing training of clinical and engineering staff as well as two follow-up evaluations are described.

Accurate classification of MLH1/MSH2 missense variants with multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR)

Lynch syndrome, also known as hereditary nonpolyposis colon cancer (HNPCC), is the most common known genetic syndrome for colorectal cancer (CRC). MLH1/MSH2 mutations underlie approximately 90% of Lynch syndrome families. A total of 24% of these mutations are missense. Interpreting missense variation is extremely challenging. We have therefore developed multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR), a bioinformatic algorithm that effectively classifies MLH1/MSH2 deleterious and neutral missense variants. We compiled a large database (n>300) of MLH1/MSH2 missense variants with associated clinical and molecular characteristics. We divided this database into nonoverlapping training and validation sets and tested MAPP-MMR. MAPP-MMR significantly outperformed other missense variant classification algorithms (sensitivity, 94%; specificity, 96%; positive predictive value [PPV] 98%; negative predictive value [NPV], 89%), such as SIFT and PolyPhen. MAPP-MMR is an effective bioinformatic tool for missense variant interpretation that accurately distinguishes MLH1/MSH2 deleterious variants from neutral variants.

Beyond good intentions: lessons on equipment donation from an African hospital

OBJECTIVE

In 2000, a referral hospital in the Gambia accepted a donation of oxygen concentrators to help maintain oxygen supplies. The concentrators broke down and were put into storage. A case study was done to find the reasons for the problem and to draw lessons to help improve both oxygen supplies and the success of future equipment donations.

METHODS

A technical assessment of the concentrators was carried out by a biomedical engineer with relevant expertise. Semi-structured interviews were undertaken with key informants, and content analysis and inductive approaches were applied to construct the history of the episode and the reasons for the failure.

FINDINGS

Interviews confirmed the importance of technical problems with the equipment. They also revealed that the donation process was flawed, and that the hospital did not have the expertise to assess or maintain the equipment. Technical assessment showed that all units had the wrong voltage and frequency, leading to overheating and breakdown. Subsequently a hospital donations committee was established to oversee the donations process. On-site biomedical engineering expertise was arranged with a nongovernmental organization (NGO) partner.

CONCLUSION

Appropriate donations of medical equipment, including oxygen concentrators, can be of benefit to hospitals in resource-poor settings, but recipients and donors need to actively manage donations to ensure that the donations are beneficial. Success requires planning, technical expertise and local participation. Partners with relevant skills and resources may also be needed. In 2002, WHO produced guidelines for medical equipment donations, which address problems that might be encountered. These guidelines should be publicized and used.