Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Characterizing surface roughness by speckle pattern analysis

Speckle photography is a non-destructive technique for making moderate sensitivity measurements for strain, rotation, vibration, plane displacements, and surface texture. This paper presents characterization of surface roughness by studying speckle patterns correlation and visibility during object displacement

64-slice CT imaging in a case of total anomalous pulmonary venous circulation

For long, catheter angiography has been the investigation of choice for the diagnosis of congenital anomalies of the heart such as total anomalous pulmonary venous circulation (TAPVC). In the last few years, MRI and multislice CT scan have also been introduced for this purpose. We report a case where 64-slice CT scan was found very useful in the evaluation of TAPVC

Assessment of emission and performance of compression ignition engine with varying injection timing

Engine performance improvement and exhaust emissions reduction are the two most important issues to develop a more efficient engine with less environmental impact. For a diesel engine, injection timing is one of the major parameters that affect the engine performance and emissions. Now-a-days, alternative fuels for internal combustion engines have created interest among the researchers around the world due to the limited reserve and rapid depletion of petroleum based fuels. In this paper, studies focused on characterizing influence of injection timing on engine performance and exhaust emissions have been critically reviewed where diesel, biodiesel, alcohol and other alternative fuels are used. In case of diesel fuel, advancement in injection timing results in lower carbon monoxide (CO) and hydrocarbon (HC) emission; though it increases nitrogen oxides (NOx) emission. Advance injection timing increases brake thermal efficiency (BTE) and decreases brake specific fuel consumption (BSFC). Biodiesel-diesel blends produce more HC and CO emission, but reduce NOx emission when injection timing is retarded. Advancement in injection timing results in higher exhaust gas temperature with increase of biodiesel percentage in the blends

Impact of palm, mustard, waste cooking oil and Calophyllum inophyllum biofuels on performance and emission of CI engine

Present energy situation of the world is unsustainable due to unequal geographical distribution of natural wealth as well as environmental, geopolitical and economical concerns. Ever increasing drift of energy consumption due to growth of population, transportation and luxurious lifestyle has motivated researchers to carry out research on biofuels as a sustainable alternative fuel for diesel engine. Renewability, cost effectiveness and reduction of pollutants in exhaust gas emission are promoting biofuels as a suitable substitute of diesel fuel in near future. This paper reviews the suitability of feedstock and comparative performance and emission of palm, mustard, waste cooking oil (WCO) and Calophyllum inophyllum biofuels with respect to diesel fuel from various recent publications. Probable analysis of performance and emission of biofuel is also included in further discussion. Palm oil has versatile qualities in terms of productivity, oil yield and land utilization. But tremendous demand of edible oil is motivating the use of non-edible vegetable oils as biofuel feedstock. Mustard oil is a promising new biofuel especially regarding NO_x reduction. WCO is one of the most economic sources of biofuel which efficiently helps in liquid waste management and prevents recycling of used oil, injurious to human health. C inophyllum is completely non-edible and trans-esterified oil shows similar engine performance and emission characteristics like other biofuels. Limited data were published regarding mustard and C inophyllum as their use as biofuel is still in primary state compared to palm or WCO. Therefore, in depth research needs to be carried out on these two oils to use them effectively as alternative fuels

Performance and emission of multi-cylinder diesel engine using biodiesel blends obtained from mixed inedible feedstocks

Biodiesel production from non-edible feedstock is now being taken into careful consideration to avoid the negative impact of using edible oils as biodiesel feedstock. This is a study on the combustion, engine performance and emission of a multi cylinder diesel engine fueled with mixed biodiesel blends prepared from two non-edible feedstock kapok and moringa. The kapok-moringa mixed biodiesel blends showed 6-9% higher brake specific fuel consumption and 5-7% lower brake power compared to diesel fuel (B0). However, engine performance of kapok-moringa mixed biodiesel was found comparable with kapok and moringa biodiesel as the performance parameters varied slightly among all tested biodiesels. Average NO and CO2 emissions for kapok-moringa mixed biodiesels were found 14-17% and 1-3% higher than B0 respectively. On the contrary average HC and CO emissions of kapok-moringa mixed biodiesels were 23-38% and 16-31% lower than B0 respectively. As a conclusion, 10% and 20% kapok-moringa mixed biodiesel blends can be used in diesel engines without any modifications

Combustion, performance and emission characteristics of a DI diesel engine fueled with Brassica juncea methyl ester and its blends

In this study, mustard biodiesel (B100) was produced from low quality crude mustard oil and tested in a four-cylinder, direct-injection, diesel engine to investigate the combustion, performance and emission characteristics of the engine at different engine speeds and full load conditions. Biodiesel and its blends showed increased peak cylinder pressure and reduced ignition delay when compared to diesel fuel (B0). The pre-mixed combustion phase and the start of injection timing for B100 and its blends took place earlier than B0. During engine performance tests, 10% and 20% biodiesel blends showed 4–8% higher brake specific fuel consumption and 9–13% lower brake power compared to diesel fuel. Engine emissions tests showed 9–12% higher NO, 19–42% lower HC and CO for B100 blends compared to B0. In conclusion, 10% and 20% B100 blends can be used in diesel engines without modifications

Production of palm and jatropha based biodiesel and investigation of palm-jatropha combined blend properties, performance, exhaust emission and noise in an unmodified diesel engine

An ever increasing drift of energy consumption, unequal geographical distribution of natural wealth and the quest for low carbon fuel for a cleaner environment are sparking off the production and use of biodiesels in many countries around the globe. In this work, palm biodiesel and jatropha biodiesel were produced from the respective crude vegetable oils through transesterification, and the different physicochemical properties of the produced biodiesels have been presented, and found to be acceptable according to the ASTM standard of biodiesel specification. This paper presents experimental results of the research carried out to evaluate the BSFC, engine power, exhaust and noise emission characteristics of a combined palm and jatropha blend in a single-cylinder diesel engine at different engine speeds ranging from 1400 to 2200 rpm. Though the PBJB5 and PBJB10 biodiesels showed a slightly higher BSFC than diesel fuel, all the measured emission parameters and noise emission were significantly reduced, except for NO emission. CO emissions for PBJB5 and PBJB10 were 9.53% and 20.49% lower than for diesel fuel. By contrast, HC emissions for PBJB5 and PBJB10 were 3.69% and 7.81% lower than for diesel fuel. The sound levels produced by PBJB5 and PBJB10 were also reduced by 2.5% and 5% compared with diesel fuel due to their lubricity and damping characteristics