5 research outputs found
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Synthèse et caractérisations d'une nouvelle famille de copolymères fluorés pour l'optique non linéaire quadratique
Different types of fluorinated copolymers poly (arylène ether) were synthesized by polycondensation, the substitution of C-H groups by C-F groups leading to a decrease of the optical losses at 1.55 ¤m, which is interesting for the applications in the telecommunications domain. In order to accomplish this purpose, various types of chromophores, which contain tricyanovinyle groups as acceptor groups have been synthesized, and then they have been grafted on these polymers to have good properties in second order nonlinear optics NLO. Thermal analysis shows high thermal stability up to 350 °C and high glass transition temperature (Tg> 160 ° C). The refractive indices which were measured by ellipsometry were around 1.55. The second order susceptibility NLO coefficients (d33) determined by second harmonic generation (SHG) of the various films poled by electric field (Corona discharge) were found around 15 pm.V-1 at 1.907 ¤m, and the thermal stability of poled films has been observed up to 130 ° C. During the poling, a reversible fall of the SHG signal during the cooling has been observed around 120 °C. Various hypotheses have been studied to explain this fall. Finally the existence of a sub-glass transition in fluorinated copolymers was highlighted by dielectric analysis. Its origins seems strongly linked to inter-chains dipolar interactionsDifférents types de copolymères fluorés de poly (arylène éther) ont été synthétisés par polycondensation, le remplacement des groupes C-H par des groupes C-F permettant de diminuer les pertes optiques à 1,55 ¤m en vue d¤applications dans le domaine des télécommunications. Dans ce but, différents types de chromophores, qui contiennent des groupes accepteurs tricyanovinyle ont été synthétisés; ensuite ils ont été greffés de manière covalente sur ces polymères afin d¤avoir de bonnes propriétés en ONL du second ordre. Les analyses thermiques ont montré des stabilités thermiques jusqu¤à 350 °C et des températures de transition vitreuse élevées (Tg>160 °C). Les indices de réfraction mesurés par ellipsométrie sont voisins de 1.55. Les coefficients de susceptibilité non linéaire de second ordre (d33) déterminés par génération de second harmonique (GSH) des différents films orientés sous champ électrique (décharge Corona) ont été trouvés voisins de 15 pm.V-1 à 1,907 ¤m, et une stabilité thermique de l¤orientation a été observée jusqu¤à 130 °C. Pendant les orientations, une chute réversible du signal de GSH au cours du refroidissement a été observée autour de 120 °C. Différents hypothèses ont été étudiées pour expliquer cette chute. Finalement l¤existence d¤une sous-transition vitreuse dans les copolymères fluorés a été mise en évidence par analyse diélectrique. Son origine semble fortement liée aux interactions dipolaires inter-chaîne
Synthesis and characterization of a new family of fluorinated copolymers for quadratic non linear optics
Différents types de copolymères fluorés de poly (arylène éther) ont été synthétisés par polycondensation, le remplacement des groupes C-H par des groupes C-F permettant de diminuer les pertes optiques à 1,55 m en vue d applications dans le domaine des télécommunications. Dans ce but, différents types de chromophores, qui contiennent des groupes accepteurs tricyanovinyle ont été synthétisés; ensuite ils ont été greffés de manière covalente sur ces polymères afin d avoir de bonnes propriétés en ONL du second ordre. Les analyses thermiques ont montré des stabilités thermiques jusqu à 350 C et des températures de transition vitreuse élevées (Tg>160 C). Les indices de réfraction mesurés par ellipsométrie sont voisins de 1.55. Les coefficients de susceptibilité non linéaire de second ordre (d33) déterminés par génération de second harmonique (GSH) des différents films orientés sous champ électrique (décharge Corona) ont été trouvés voisins de 15 pm.V-1 à 1,907 m, et une stabilité thermique de l orientation a été observée jusqu à 130 C. Pendant les orientations, une chute réversible du signal de GSH au cours du refroidissement a été observée autour de 120 C. Différents hypothèses ont été étudiées pour expliquer cette chute. Finalement l existence d une sous-transition vitreuse dans les copolymères fluorés a été mise en évidence par analyse diélectrique. Son origine semble fortement liée aux interactions dipolaires inter-chaînesDifferent types of fluorinated copolymers poly (arylène ether) were synthesized by polycondensation, the substitution of C-H groups by C-F groups leading to a decrease of the optical losses at 1.55 m, which is interesting for the applications in the telecommunications domain. In order to accomplish this purpose, various types of chromophores, which contain tricyanovinyle groups as acceptor groups have been synthesized, and then they have been grafted on these polymers to have good properties in second order nonlinear optics NLO. Thermal analysis shows high thermal stability up to 350 C and high glass transition temperature (Tg> 160 C). The refractive indices which were measured by ellipsometry were around 1.55. The second order susceptibility NLO coefficients (d33) determined by second harmonic generation (SHG) of the various films poled by electric field (Corona discharge) were found around 15 pm.V-1 at 1.907 m, and the thermal stability of poled films has been observed up to 130 C. During the poling, a reversible fall of the SHG signal during the cooling has been observed around 120 C. Various hypotheses have been studied to explain this fall. Finally the existence of a sub-glass transition in fluorinated copolymers was highlighted by dielectric analysis. Its origins seems strongly linked to inter-chains dipolar interactionsCACHAN-ENS (940162301) / SudocSudocFranceF
Synthesis and characterizations of highly fluorinated poly(arylene ether)s for quadratic nonlinear optics
New highly fluorinated poly(arylene ether sulfone)s (FPAES), poly(arylene ether ketone)s (FPAEK), and poly(arylene ether)s with several types of NLO chromophores as pendant groups were obtained by a polycondensation reaction using very mild conditions. The different polymer structures were designed with the objective to investigate the influence of both the polarity of the chromophore and the nature of the tether between the NLO chromophore and the chain. The resulting copolymers have glass transition temperatures (Tg\u2019s) varying between 160 and 215\ub0C, and they are stable up to 280\ub0C under nitrogen. Although these copolymers are soluble in common organic solvents, cyclohexanone gave the best film quality and was used for the film preparation. After optimization of the poling conditions, the in situ second harmonic generation (SHG) measurements gave nonresonant values of the second-order susceptibilities d33 ranging from 2 to 8 pm/V, and the SHG signals of the poled polymer films were found to be thermally stable below 130\ub0C. Although being comparable with the values obtained for similar polymers and chromophores in the literature, d\u2083\u2083 are smaller than those obtained for more conventional NLO polymers like PMMA-Disperse Red One (PMMA-DR1), which was taken as a reference. An unusual drop of the SHG signal during cooling was found in the thermally assisted orientation process. This drop occurred at a characteristic temperature below Tg. In this relaxation process which has never been observed, intra- and interchain dipolar interactions are shown to play an important role, which is amplified in the case of chromophores which have their donor group embedded in the main chain, connected by two rigid tethers.Peer reviewed: YesNRC publication: Ye