Prehabilitation in hepato-pancreato-biliary surgery: A systematic review and meta-analysis. A necessary step forward evidence-based sample size calculation for future trials.

INTRODUCTION: Prehabilitation is defined as preoperative conditioning of patients in order to improve post-operative outcomes. Some studies showed an increase in functional recovery following colorectal surgery, but its effect in hepato-pancreato-biliary (HPB) surgery is unclear. The aim of this study was to realize a systematic literature review and meta-analysis on the current available evidence on prehabilitation in HPB surgery. MATERIALS AND METHODS: A systematic review and a metanalysis were carried out on prehabilitation (physical, nutritional and psychological interventions) in HPB surgery (2009-2019). Assessed outcomes were postoperative complications, length of stay (LOS), 30-day readmission, and mortality. MAIN RESULTS: Four studies among the 191 screened were included in this systematic review (3 randomized controlled trials, 1 case-control propensity score study), involving 419 patients (prehabilitation group, n=139; control group, n=280). After pooling, no difference was observed on LOS ((-4.37 days [95% CI: -8.86; 0.13]) or postoperative complications (RR 0.83 [95%CI: 0.62; 1.10]), reported by all the included studies. Two trials reported on readmission rate, but given the high heterogeneity, a meta-analysis was not realized. No deaths were reported among the included studies. CONCLUSION: No effect of prehabilitation programs in HPB surgery was observed on LOS or postoperative complications rate. Future trials with standardized outcomes of measure, and adequately powered samples calculations are thus required. PROSPERO REGISTRATION: CRD42020165218.

2D self-assembly of phenylene-vinylene tectons at the liquid-highly oriented pyrolytic graphite interface: from chain length effects to anisotropic guest-host dynamics.

Here we report the synthesis and characterization of a series of new phenylene-vinylene tectons. The study by scanning tunneling microscopy of their supramolecular self-assembly at the interface between a phenyloctane solution and highly oriented pyrolytic graphite  demonstrates that variation of concentration and length of alkyl chains led to the formation of different networks, a compact one and a nanoporous one, with a fine control of the lattice parameters. The study of guest-host properties of the nanoporous network revealed a selectivity toward guest compounds according to their shape and size. Moreover, the statistical analysis of pore-to-pore guest dynamics evidences an anisotropic diffusion process.

Electronic energy and electron transfer processes in photoexcited donor-acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units.

We investigate the photophysical properties of organic donor-acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units linked by a non-conjugated flexible bridge in solution using complementary optical spectroscopy techniques. When these molecules are diluted in dichloromethane solution, energy transfer from the triphenylene to the perylene diimide excited moieties is evidenced by time-resolved fluorescence measurements resulting in a quenching of the emission from the triphenylene moieties. Simultaneously, another quenching process that affects the emission from both donor and acceptor units is observed. Solution ultrafast transient absorption measurements provide evidence of photo-induced charge transfer from either the donor or the acceptor depending upon the excitation. Overall, the analysis of the detailed time-resolved spectroscopic measurements carried out in the dyad and triad systems as well as in the triphenylene and perylene diimide units alone provides useful information both to better understand the relations between energy and charge transfer processes with molecular structures, and for the design of future functional dyad and triad architectures based on donor and acceptor moieties for organic optoelectronic applications.

Photophysical, amplified spontaneous emission and charge transport properties of oligofluorene derivatives in thin films.

We investigate the photophysical and amplified spontaneous emission properties of a series of monodisperse solution-processable oligofluorenes functionalized with hexyl chains at the C9 position of each fluorene unit. Thin films of these oligofluorenes are then used in organic field-effect transistors and their charge transport properties are examined. We have particularly focused our attention on the influence of oligofluorene length on the absorption and steady-state fluorescence spectra, on the HOMO/LUMO energy levels, on the photoluminescence lifetime and quantum yield as well as on the amplified spontaneous emission properties and the charge carrier mobilities. Differential scanning calorimetry and X-ray diffraction measurements demonstrate that, among all oligofluorene derivatives used in this study, only the structure and morphology of the pentafluorene film is significantly modified by a thermal treatment above the glass transition temperature, resulting in a 9 nm blue-shift of the fluorescence spectrum without significant changes in the photoluminescence quantum yield and in the amplified spontaneous emission threshold. In parallel, hole field-effect mobility is significantly increased from 8.6 × 10(-7) to 3.8 × 10(-5) cm(2) V(-1) s(-1) upon thermal treatment, due to an increase of crystallinity. This study provides useful insights into the morphological control of oligofluorene thin films and how it affects their photophysical and charge transport properties. Moreover, we provide evidence that, because of the low threshold, the tunability of the amplified spontaneous emission and the photostability of the films, these oligofluorenes are promising candidates for organic solid-state laser applications.

[Perioperative conflicts between anaesthesiologists and surgeons: ethics and professionalism]. / Conflits en période périopératoire: un enjeu collectif, éthique et professionnel.

In the perioperative period, several potential conflicts between anaesthetists/intensive care specialists and surgeons may exist. They are detrimental to the quality of patient care and to the well-being of the teams. They are a source of medical errors and contribute to burn-out. Patients can become the victims of such conflicts, which deserve ethical reflection. Their resolution through analysis and shared solutions is necessary. This article seeks to analyse these conflicts, taking into account their specificities and constraints. In order to understand this context, it is important to consider the specificities of each group involved and the records of such situations. Several factors can prevent these conflicts, first and foremost the patients themselves and the quality of the care that is provided. Medical deontology aims mainly at preventing and resolving these conflicts. Generally speaking, the quality approach which is increasingly applied in health care institutions (involving declarations of adverse events, morbidity/mortality reviews, benchmarking, analysis and improvement of practices, etc.) also contributes to the prevention and resolution of disagreements. The teaching of communication techniques that begins with the initial training, the evaluation of team behaviours (through simulation training for example), the respect of others' constraints, particularly when it comes to learning, as well as transparency regarding conflicts of interests, are all additional elements of conflict prevention. Lastly, conflicts may at times be caused by deviant behaviours, which must be met with a clear and uncompromising collective and institutional approach. This article concludes by offering a standardised approach for conflict resolution.

A comparison of two techniques for inserting the Airtraq laryngoscope in morbidly obese patients.

We postulated that video-controlled tracheal intubation with the Airtraq laryngoscope using the reverse manoeuvre instead of the standard technique of insertion could facilitate the airway management of morbidly obese patients. For the reverse manoeuvre the laryngoscope is inserted 180 degrees opposite to that recommended, and once in place rotated into the conventional pharyngeal position. Eighty (40 lean and 40 morbidly obese) ASA I-III adult patients were randomly allocated to four equal groups to compare the standard technique to the reverse manoeuvre for inserting the Airtraq laryngoscope. Video-controlled and clinical tracheal intubation characteristics were recorded. The reverse manoeuvre did not influence tracheal intubation characteristics in the group of lean patients. In the group of morbidly obese patients, the standard technique of insertion was not satisfactory in 20% of cases and the reverse manoeuvre facilitated, speeded and secured tracheal intubation.