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

Advancing thermal performance through vortex generators morphing

AbstractThe design of rigid vortex generators (RVG) influences the thermal performance of various technologies. We employed Discrete Adjoint-Based Optimization to show the optimal development of vortex generators. Under turbulent flow conditions, different bi-objective functions on the RVG design were examined. Specifically, we aimed at an optimal RVG shape that minimizes the pressure drop and maximizes the local heat transfer in a rectangular channel. We show that an optimal design of an RVG can be obtained using computational fluid dynamics in conjunction with the Pareto Front at a computational cost of the order ~$$O(10^{-1})$$ O ( 10 - 1 ) . We obtained three essential vortex generator shapes based on the RVG morphing technique. Compared to the baseline geometry of a delta winglet pair DWP, the first morphed design reduced the pressure drop by $$39\%$$ 39 % , however, at the expense of a $$21\%$$ 21 % reduction in the Nusselt number. The second vortex generator design enhanced the heat transfer by $$18\%$$ 18 % , however, at the cost of a significant increase in pressure drop of about $$40\%$$ 40 % . The final morphed design achieved the highest thermal performance factor of 1.28, representing a heat transfer enhancement of $$6\%$$ 6 % with a moderate increase in pressure drop of about $$13\%$$ 13 % compared to DWP vortex generators. Furthermore, we investigated the effect of introducing different size holes on the mass reduction of vortex generators and their thermal performances. The mass of vortex generators can be reduced by $$9\%$$ 9 % and with an increase of $$7\%$$ 7 % in thermal performance factor concerning the DWP baseline. The findings of this study will lead to highly efficient lightweight heat exchangers.</jats:p

Thermo-hydraulic performance of concentric tube heat exchangers with turbulent flow: Predictive correlations and iterative methods for pumping power and heat transfer

International audienc

Advancing thermal performance through vortex generators morphing

Abstract The design of rigid vortex generators (RVG) influences the thermal performance of various technologies. We employed Discrete Adjoint-Based Optimization to show the optimal development of vortex generators. Under turbulent flow conditions, different bi-objective functions on the RVG design were examined. Specifically, we aimed at an optimal RVG shape that minimizes the pressure drop and maximizes the local heat transfer in a rectangular channel. We show that an optimal design of an RVG can be obtained using computational fluid dynamics in conjunction with the Pareto Front at a computational cost of the order ~ $$O(10^{-1})$$ O ( 10 - 1 ) . We obtained three essential vortex generator shapes based on the RVG morphing technique. Compared to the baseline geometry of a delta winglet pair DWP, the first morphed design reduced the pressure drop by $$39\%$$ 39 % , however, at the expense of a $$21\%$$ 21 % reduction in the Nusselt number. The second vortex generator design enhanced the heat transfer by $$18\%$$ 18 % , however, at the cost of a significant increase in pressure drop of about $$40\%$$ 40 % . The final morphed design achieved the highest thermal performance factor of 1.28, representing a heat transfer enhancement of $$6\%$$ 6 % with a moderate increase in pressure drop of about $$13\%$$ 13 % compared to DWP vortex generators. Furthermore, we investigated the effect of introducing different size holes on the mass reduction of vortex generators and their thermal performances. The mass of vortex generators can be reduced by $$9\%$$ 9 % and with an increase of $$7\%$$ 7 % in thermal performance factor concerning the DWP baseline. The findings of this study will lead to highly efficient lightweight heat exchangers

Topology optimization of rectangular parallel plate heat exchanger unit

International audienc

Idiopathic pleuroparenchymal fibroelastosis: first case report in Lebanon

Abstract Idiopathic pleuroparenchymal fibroelastosis (IPPFE) was initially described by Amitani et al. in Japan. It is characterized by visceral pleural fibrosis and adjacent lung parenchymalfibroelastosis with striking upper lobe predominance. Because of its rarity and the lack of clear diagnostic criteria, the prevalence of the disease is still unclear. We report the first case of IPPFE in Lebanon and the second one in the Arab World. A 37-year-old Iraqi man was admitted to the hospital with progressive dyspnea on exertion occurring since 2 years and associated with dry cough. Histo-pathologic results reported a prominent interstitial fibrosis mainly in upper parts, and no granulomatous tissue was detected. Therefore, the diagnosis of IPPFE was made. The IPPFE is a distinct entity that requires meticulous clinico-pathological correlation for an adequate diagnosis and a close follow-up as this entity can progress into more advanced stages.</jats:p

Cardiac amyloidosis with overt multiple myeloma presenting with pulmonary effusion: case report

Abstract Amyloidosis was initially described by Nicolaes Fonteyn in 1639. It is caused by the deposition of soluble immunoglobulin light chains as insoluble fibrils and can affect any organ including the heart, nervous system, dermis and subcutaneous tissue, kidneys and liver. This is a rare case of cardiac amyloidosis occurring with multiple myeloma and pleural effusion. A 65-year-old Arab woman, nonsmoker, nonalcoholic, known to have hypothyroidism and multiple myeloma, presented to the hospital with dyspnea and basilar crackles. Workup was done to exclude leukemia. Cardiac echography showed features of amyloidosis. Cardiac amyloidosis occurring with multiple myeloma and pleural effusion is rare. However, it is stated that 10–15% of amyloidosis patients might develop multiple myeloma (MM).</jats:p

Surrogate-based optimization of the attack and inclination angles of a delta winglet pair vortex generator in turbulent channel flow

International audienc