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

Topological analysis of the electron density in the N-heterocyclic carbene triruthenium cluster [Ru3(µ-H)2(µ3- MeImCH)(CO)9] (Me2im = l,3-dimethylimidazol-2-ylidene)

The bonding in the triruthenium dihydrido cluster compound [Ru3(μ-H)2(μ3-κ2-MeImCH)(CO)9] (1), which contains a face-capping N-heterocyclic carbene ligand (MeImCH) derived from the activation of two C−H bonds of 1,3-dimethylimidazol-2-ylidene (Me2Im), has been studied from the perspective of the atoms in molecules (AIM) quantum theory. Although the AIM approach recognizes the existence of a bond path in only one of the Ru−Ru edges of complex 1, i.e., that unbridged by the hydride ligands Ru(1)−Ru(3), the non-negligible values for the delocalization indexes of the hydride-bridged Ru−Ru edges indicate a delocalized kind of metal−metal interaction in these edges. In fact, a multicenter (5c-6e) interaction involving the Ru3H2 core of the molecule can be proposed. The three-atom C−N−C bridge that spans the Ru(1)−Ru(3) edge of 1 does not delocalize the electronic density of the bridged metal atoms as efficiently as bridges comprising just one atom, such as hydride or CH. The topological parameters of the three Ru−C bonds between the metal atoms and the face-capping NHC ligand are very similar, and they confirm that these interactions are pure σ-bonds. The analysis of the topological parameters for the bonds of the NHC ligand confirms the presence of π-electron delocalization within the five-membered ring as well as the existence of some double-bond character in the interaction of the carbene C atom with the adjacent N atoms

Theoretical topological analysis of the electron density in a series of triosmium carbonyl clusters: [Os(3)(CO)(12)], [Os(3)(mu-H)(2)(CO)(10)], [Os(3)(mu-H)(mu-OH)(CO)(10)], and [Os(3)(mu-H)(mu-Cl)(CO)(10)]

A number of local and integral topological parameters of the electron density for the triosmium triangular carbonyl clusters [Os3(CO)12] (1), [Os3(μ-H)2(CO)10] (2), [Os3(μ-H)(μ-OH)(CO)10] (3), and [Os3(μ-H)(μ-Cl)(CO)10] (4) have been calculated and interpreted under the perspective of the relativistic and non-relativistic Quantum Theory of Atoms in Molecules (QTAIM). These results have allowed a comparison between topological properties of related but different atom–atom interactions, such as different Os–Os bond orders, H-bridged versus X-bridged (X = OH, Cl) and ligand-unbridged Os–Os interactions, and Os–H versus Os–OH and Os–Cl interactions. For compound 1, an interaction of 3c–2e type between the three metal atoms has been found. The local topological parameters of the unbridged Os–Os bonds in compound 2 differ considerably from those of the bridged Os–Os bond, for which a bond path was nevertheless observed. The calculated topological indexes indicate that bridging OH and Cl ligands are more efficient than bridging hydride ligands in delocalizing the electron density of bridged metal atoms; in fact, no direct bond path has been found for the interaction between bridged Os atoms in 3 or 4, although a non-negligible delocalization index δ(Os⋯Os) has been obtained for these non-bonding interactions. A multicenter 4c–4e interaction is proposed to exist in the bridged parts, Os2(μ-H)(μ-X) (X = H (2), OH (3), Cl (4)), of compounds 2–4. Compared with compound 2, the smaller electron density shared by the bridged Os atoms in compounds 3 and 4 is compensated by a greater electron density shared by the atoms in Os–X (X = O, Cl) bonds