6 research outputs found
Exploring the cost-effectiveness of high versus low perioperative fraction of inspired oxygen in the prevention of surgical site infections among abdominal surgery patients in three low- and middle-income countries
No full textBackground: This study assessed the potential cost-effectiveness of high (80–100%) vs low (21–35%) fraction of inspired oxygen (FiO2) at preventing surgical site infections (SSIs) after abdominal surgery in Nigeria, India, and South Africa. Methods: Decision-analytic models were constructed using best available evidence sourced from unbundled data of an ongoing pilot trial assessing the effectiveness of high FiO2, published literature, and a cost survey in Nigeria, India, and South Africa. Effectiveness was measured as percentage of SSIs at 30 days after surgery, a healthcare perspective was adopted, and costs were reported in US dollars (216 compared with 6 (95% confidence interval [CI]: −1) difference in costs. In India, the average cost for high FiO2 was 195 for low FiO2 leading to a −15 to −1164 compared with 93 (95% CI: −65) difference in costs. The high FiO2 arm had few SSIs, 7.33% compared with 8.38% for low FiO2, leading to a −1.05 (95% CI: −1.14 to −0.90) percentage point reduction in SSIs. Conclusion: High FiO2 could be cost-effective at preventing SSIs in the three countries but further data from large clinical trials are required to confirm this
Use of Telemedicine for Post-discharge Assessment of the Surgical Wound: International Cohort Study, and Systematic Review with Meta-analysis
No full textObjective: This study aimed to determine whether remote wound reviews using telemedicine can be safely upscaled, and if standardised assessment tools are needed. Summary background data: Surgical site infection is the most common complication of surgery worldwide, and frequently occurs after hospital discharge. Evidence to support implementation of telemedicine during postoperative recovery will be an essential component of pandemic recovery. Methods: The primary outcome of this study was surgical site infection reported up to 30-days after surgery (SSI), comparing rates reported using telemedicine (telephone and/or video assessment) to those with in-person review. The first part of this study analysed primary data from an international cohort study of adult patients undergoing abdominal surgery who were discharged from hospital before 30-days after surgery. The second part combined this data with the results of a systematic review to perform a meta-analysis of all available data conducted in accordance with PRIMSA guidelines (PROSPERO:192596). Results: The cohort study included 15,358 patients from 66 countries (8069 high, 4448 middle, 1744 low income). Of these, 6907 (45.0%) were followed up using telemedicine. The SSI rate reported using telemedicine was slightly lower than with in-person follow-up (13.4% vs. 11.1%, P<0.001), which persisted after risk adjustment in a mixed-effects model (adjusted odds ratio: 0.73, 95% confidence interval 0.63-0.84, P<0.001). This association was consistent across sensitivity and subgroup analyses, including a propensity-score matched model. In nine eligible non-randomised studies identified, a pooled mean of 64% of patients underwent telemedicine follow-up. Upon meta-analysis, the SSI rate reported was lower with telemedicine (odds ratio: 0.67, 0.47-0.94) than in-person (reference) follow-up (I2=0.45, P=0.12), although there a high risk of bias in included studies. Conclusions: Use of telemedicine to assess the surgical wound post-discharge is feasible, but risks underreporting of SSI. Standardised tools for remote assessment of SSI must be evaluated and adopted as telemedicine is upscaled globally
Global warming and malaria: a call for accuracy
No full textFor more than a decade, malaria has held a prominent place in speculations on the impacts of global climate change. Mathematical models that “predict? increases in the geographic distribution of malaria vectors and the prevalence of the disease have received wide publicity. Efforts to put the issue into perspective1, 2, 3, 4 and 5 are rarely quoted and have had little influence on the political debate. The model proposed by Frank C Tanser and colleagues6 in The Lancet and the accompanying Commentary by Simon Hales and Alistair Woodward7 are typically misleading examples.The relation between climate and malaria transmission is complex and varies according to location,2 yet Tanser et al base their projections on thresholds derived from a mere 15 African locations. Slight adjustments of values assigned to such thresholds and rules can influence spatial predictions strongly.8 The authors invest considerable effort in assessing the sensitivity of their model to climate change scenarios but do not report the internal sensitivities to thresholds and rules. The predictive skill of their model is low (63% sensitivity, 95% CI 61–65%) but they consider projections acceptable if prevalence is projected “to within a month? (presumably +/- 1 month?), thereby biasing their model towards success. A model covering an entire year in a parasite-positive site would always be correct, although in such areas it would be relatively insensitive to climate. By contrast, sites in which transmission is seasonal would provide a more reliable test of accuracy, but estimation is more difficult because climate sensitivity is greater. Furthermore, because parasite clearance in communities is not instantaneous,9 spot samples of parasitaemia on survey dates are not a suitable indicator of the duration of the transmission season. Lastly, “person/months? are unsuitable as a measure of transmission: an extension of season from 1 to 4 months will have more impact than from 10 to 12 months. According to their model, an extension of transmission from 11 to 12 months results in 106 more person/months in a population of 106 people, whereas an extension from 1 to 5 months gives the same increase in a population of 250·000.What Tanser and colleagues have modelled is merely the duration of the transmission season, which they interpret as “heightened transmission? and increased incidence. A greater failing is their reliance on “parasite-ratio studies?. The relations between transmission season and parasite prevalence, and parasite prevalence and clinical disease, are unclear but unlikely to be linear. Moreover, they use 1995 data for human populations, although these are projected to double by 2030. In addition, the proportion living in urban areas—with a specific climate10 and orders of magnitude less malaria transmission11 and 12—is projected to rise from 37% to 53%.13 For all these reasons, we do not accept the model as a “baseline against which interventions can be planned?.It is regrettable that many involved in this debate ignore the rich heritage of literature on the subject. For example, in 1937, in his classic textbook,14 L W Hackett stated: “Everything about malaria is so moulded and altered by local conditions that it becomes a thousand different diseases and epidemiological puzzles. Like chess, it is played with a few pieces, but is capable of an infinite variety of situations?. A pressing question in Hackett's time was the changing distribution of the disease in Europe. On the role of climate, he wrote: “Certainly, climate lays down the broad lines of malaria distribution…Nevertheless, although this is a very simple and plausible explanation…even the early malariologists felt that there was something unsatisfactory about it…malaria has not so much receded as it has contracted, oftentimes toward the north…Thus in Germany it is the northern coast which is still malarious, the south is free…There is, therefore, no climatic reason why (malaria) should have abandoned south Germany or the French Riviera?.We quote Hackett because we feel that the classic components of science—unbiased observation and systematic experimentation—cannot be sidestepped with models that omit many of his chess pieces. Yet Hales and Woodward7 begin by stating: “The present geographical distribution of malaria is explained by a combination of environmental factors (especially climate) and social factors (such as disease-control measures)?. In our opinion, “even the early malariologists? would surely disagree: much of the decline of malaria in Europe took place without control measures during a period when the climate was warming.The text by Hales and Woodward that follows displays a lack of knowledge. Thus, “Most people at risk of malaria live in areas of stable transmission…? is simply wrong. It is true that in many parts of the world malaria is termed “stable? because transmission remains relatively constant from year to year, the disease is endemic, the collective immunity is high, and epidemics are uncommon. However, in many other regions, the disease is endemic but “unstable? because annual transmission varies considerably, and the potential for epidemics is great. Climatic factors, particularly rainfall, are sometimes, but by no means always, relevant.15Again, “On the fringes of endemic zones, where transmission is limited by rainfall…there are strong seasonal patterns, and occasional major epidemics? is also wrong. In many regions, far from any “fringes?, malaria is endemic, stable, but highly seasonal. For example, in semi-arid regions of Mali, transmission is restricted to the rainy season, from July to September. The same 3 months constituted the transmission season for Plasmodium falciparum in Italy before it was eliminated.16 Paradoxically, in parts of the Sudan, rainfall is restricted to a month at most, but malaria is transmitted throughout the year. Female Anopheles gambiae survive drought and heat by resting in dwellings and other sheltered places.17 Blood feeding and transmission continue, but the mosquitoes do not develop eggs until the rains return. This phenomenon, termed gonotrophic dissociation, is remarkably similar to the winter survival strategy of Anopheles atroparvus, the principal vector of malaria in Holland until the mid 20th century.16By contrast, malaria is unstable in many regions that normally have abundant rainfall, and epidemics occur during periods of drought. An illustrative example is the catastrophic 1934–35 epidemic in Ceylon (now Sri Lanka), estimated to have killed 100·000 people.18 Worst hit was the south-western quadrant of the country, where average annual rainfall is greater than 250 cm, and malaria was endemic, but unstable and relatively infrequent. The dominant vector, Anopheles culicifacies, breeds along the banks of rivers and tends to be scarce in normal years. In the years 1928–33 there was abundant rainfall, river flow was high, A culicifacies was rare, and the human population was exceptionally malaria-free. However, after failure of two successive monsoons, the drying rivers produced colossal numbers of A culicifacies, and the resulting epidemic was exacerbated by the low collective immunity. In the drier parts of the island, where A culicifacies was dominant but transmission was more stable, immunity protected the population from the worst ravages of the disease.Hales and Woodward state that “the underlying problem? of the future “extension of seasonality? of malaria is “pollution of the atmosphere?, and call for rich countries to “recognise their obligations to the poorest by substantially reducing fossil-fuel consumption?. We understand public anxiety about climate change, but are concerned that many of these much-publicised predictions are ill informed and misleading. We urge those involved to pay closer attention to the complexities of this challenging subject. <br/
Global variation in anastomosis and end colostomy formation following left-sided colorectal resection
No full textBackground: End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods: This study comprised an analysis of GlobalSurg-1 and-2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle-and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results: In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 percent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low-compared with middle-and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion: Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone
Exploring the cost-effectiveness of high versus low perioperative fraction of inspired oxygen in the prevention of surgical site infections among abdominal surgery patients in three low- and middle-income countries
No full textSurgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
No full textFunded by DFID-MRC-Wellcome Trust Joint Global Health Trial Development Grant (MR/N022114/1) and a National Institute of Health Research (NIHR) Global Health Research Unit Grant (NIHR 17-0799)
