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Objective: Patients with comorbidities can be referred to a physician-led high-risk clinic for medical optimisation prior to elective surgery at the discretion of the surgical consultant, but the factors that influence this referral are not well understood. The aims of this study were to understand the factors that influence a surgeon's decision to refer a patient to the clinic, and how the clinic impacts on the management of complex patients., Design: Qualitative study using theoretical thematic analysis to analyse transcribed semi-structured interviews., Setting: Interviews were held in either the surgical consultant's private office or a quiet office/room in the hospital ward., Participants: Seven surgical consultants who were eligible to refer patients to the clinic., Results: When discussing the factors that influence a referral to the clinic, all participants initially described the optimisation of comorbidities and would then discuss with examples the challenges with managing complex patients and communicating the risks involved with having surgery. When discussing the role of the clinic, two related subthemes were dominant and focused on the management of risk in complex patients. The participants valued the involvement of the clinic in the decision-making and communication of risks to the patient., Conclusions: The integration of the high-risk clinic in this study appears to offer additional value in supporting the decision-making process for the surgical team and patient beyond the clinical outcomes. The factors that influence a surgeon's decision to refer a patient to the clinic appear to be driven by the aim to manage the uncertainty and risk to the patient regarding surgery and it was seen as a strategy for managing difficult and complex cases., Competing Interests: Competing interests: Dr Catherine Gibb is a consultant physician in the High Risk Clinic at the Royal Adelaide Hospital and Queen Elizabeth Hospital. The remaining authors declare no conflict of interest., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: Clinics have been established to provide preoperative medical consultations, and enable the anaesthetist and surgeon to deliver the best surgical outcome for patients. However, there is uncertainty regarding the effect of such clinics on surgical, in-hospital and long-term outcomes. A systematic review of the literature was conducted to determine the effectiveness of preoperative medical consultations by internal medicine physicians for patients listed for elective surgery., Design: Systematic searches of MEDLINE, EMBASE, CINAHL, PubMed, Current Contents and the NHS Centre for Reviews and Dissemination were conducted up to 30 April 2017., Setting: Elective surgery., Study Selection: Randomised controlled trials and non-randomised comparative studies conducted in adults., Outcome Measures: Length of hospital stay, perioperative morbidity and mortality, costs and quality of life., Results: The one randomised trial reported that preadmission preoperative assessment was more effective than the option of an inpatient medical assessment in reducing the frequency of unnecessary admissions with significantly fewer surgical cancellations following admission for surgery. A small reduction in length of stay in patients was also observed. The three non-randomised studies reported increased lengths of stay, costs and postoperative complications in patients who received preoperative assessment. The timing and delivery of the preoperative medical consultation in the intervention group differed across the included studies., Conclusion: Further research is required to inform the design and implementation of coordinated involvement of physicians and surgeons in the provision of care for high-risk surgical patients. A standardised approach to perioperative decision-making processes should be developed with a clear protocol or guideline for the assessment and management of surgical patients., Competing Interests: Competing interests: CLG is a consultant physician in the High Risk Clinic at the Royal Adelaide Hospital and Queen Elizabeth Hospital. The remaining authors declare no conflict of interest., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Isothermal titration calorimetry was used to probe how salts influence the thermodynamics of binding of guests to cavitand 1. Studies involved six Hofmeister salts covering the range of salting-in to strongly salting-out. The latter were found to reduce affinity. The cause of this was competitive binding of the weakly solvated anion to the hydrophobic pocket of the host. At the other extreme of the Hofmeister series, salts increased guest affinity. Two factors for this were evident. At low concentrations the data fitted a previously reported model that accounts for cation condensation to the outer carboxylates of the host (Carnagie, R.; Gibb, C. L. D.; Gibb, B. C., Angew. Chem., Int. Ed. 2014, 53 (43), 11498-11500). At higher concentrations, an as of yet unidentified contribution was observed that was noted to be guest dependent. Midcontinuum salts such as NaClO3 were found to enhance affinity at low concentrations, but weaken it at high concentrations; a nonmonotonic trend attributed to the aforementioned competing phenomena. In combination with previous work, the data presented here reveal that the Hofmeister effect evident in this system can be mostly attributed to solute-salt interactions.

As part of the fourth statistical assessment of modeling of proteins and ligands (sampl.eyesopen.com) prediction challenge, the strength of association of nine guests (1-9) binding to octa-acid host was determined by a combination of (1)H NMR and isothermal titration calorimetry. Association constants in sodium tetraborate buffered (pH 9.2) aqueous solution ranged from 5.39 × 10(2) M(-1) in the case of benzoate 1, up to 3.82 × 10(5) M(-1) for trans-4-methylcyclohexanoate 7. Overall, the free energy difference between the free energies of complexation of these weakest and strongest binding guests was ΔΔG° = 3.88 kcal mol(-1). Based on a multitude of previous studies, the anticipated order of strength of binding was close to that which was actually obtained. However, the binding of guest 3 (4-ethylbenzoate) was considerably stronger than initially estimated.

Kinetic analysis of the host guest complexation of a large, open molecular basket and a highly complementary adamantoid guest reveals that for these types of systems a dissociative mechanism is in operation. Hence, the resident adamantyl guest must completely vacate the cavity before another guest molecule can move in to replace it. As a result of the rigid nature of the host, the energy barrier to this process is relatively high, about 16 kcal mol(-1) at room temperature. Modifying the cavity of the host by dangling either a methyl group or a hydroxyl group from the portal rim alters the thermodynamic binding profile of these hosts. (1)H NMR shift data analysis also reveals that these functional groups can adjust the orientation that monosubstituted guests adopt within the cavity. Additionally, (1)H NMR studies of the binding of (E)1,4-dibromoadamantane allow the observation of two energetically similar diastereomeric complexes. An examination of this guest binding to the three hosts reveals that the interchange between the isomers is much faster than the entry and egression rates, and that the functional groups at the rim of each cavity influence both the rates of reorientation and the equilibrium relating the isomers.