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1.
Nat Mater ; 22(11): 1304-1310, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37337071

RESUMEN

The development of organic electronic applications has reached a critical point. While markets, including the Internet of Things, transparent solar and flexible displays, gain momentum, organic light-emitting diode displays lead the way, with a current market size of over $25 billion, helping to create the infrastructure and ecosystem for other applications to follow. It is imperative to design built-in sustainability into the materials selection, processing and device architectures of all of these emerging applications, and to close the loop for a circular approach. In this Perspective, we evaluate the status of embedded carbon in organic electronics, as well as options for more sustainable materials and manufacturing, including engineered recycling solutions that can be applied within the product architecture and at the end of life. This emerging industry has a responsibility to ensure a 'cradle-to-cradle' approach. We highlight that ease of dismantling and recycling needs to closely relate to the product lifetime, and that regeneration should be facilitated in product design. Materials choices should consider the environmental effects of synthesis, processing and end-product recycling as well as performance.

2.
Anesth Analg ; 138(2): 326-336, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38215711

RESUMEN

Over the last few decades, the field of anesthesia has advanced far beyond its humble beginnings. Today's anesthetics are better and safer than ever, thanks to innovations in drugs, monitors, equipment, and patient safety.1-4 At the same time, we remain limited by our herd approach to medicine. Each of our patients is unique, but health care today is based on a one-size-fits-all approach, while our patients grow older and more medically complex every year. By 2050, we believe that precision medicine will play a central role across all medical specialties, including anesthesia. In addition, we expect that health care and consumer technology will continually evolve to improve and simplify the interactions between patients, providers, and the health care system. As demonstrated by 2 hypothetical patient experiences, these advancements will enable more efficient and safe care, earlier and more accurate diagnoses, and truly personalized treatment plans.


Asunto(s)
Anestesia , Anestésicos , Humanos , Anestesia/efectos adversos , Atención a la Salud , Seguridad del Paciente
3.
Paediatr Anaesth ; 34(4): 289-292, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38130114

RESUMEN

BACKGROUND: Surgical correction of tracheobronchomalacia (TBM) has evolved greatly over the past decade, with select pediatric institutions establishing dedicated surgery and anesthesia teams to navigate the complexities and challenges of surgical airway repairs. Although anesthetic techniques have evolved internally over many years to improve patient safety and outcomes, many of these methods remain undescribed in literature. TECHNIQUE: In this article, we describe the intraoperative negative pressure suction test. This simulates the negative pressure seen in awake and spontaneously breathing patients, including the higher pressures seen during coughing which induce airway collapse in patients with TBM. Also known as the Munoz maneuver in surgical literature, this test has been performed on over 300 patients since 2015. DISCUSSION: The negative pressure suction test allows for controlled intraoperative assessment of surgical airway repairs, replaces the need for risky intraoperative wake-up tests, increases the chances of a successful surgical repair, and improves anesthetic management for emergence and extubation. We provide a guide on how to perform the test and videos demonstrating its efficacy in intraoperative airway evaluation. CONCLUSIONS: As surgeries to repair TBM become more prevalent in other pediatric institutions, we believe that pediatric patients and anesthesia providers will benefit from the insights and methods described here.


Asunto(s)
Anestésicos , Traqueobroncomalacia , Humanos , Niño , Succión , Traqueobroncomalacia/cirugía , Respiración , Extubación Traqueal
4.
J Appl Res Intellect Disabil ; 37(2): e13203, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38369311

RESUMEN

AIM: To explore the usefulness of a co-designed wordless book showing processes of receiving COVID-19 vaccines designed by, and for, adults with intellectual disabilities. METHODS: A qualitative evaluation of the resource using mixed methods. Semi-structured interviews were conducted with people with intellectual disabilities, carers and health professionals about resource content, and use. This was analysed thematically. A survey was circulated to intellectual disabilities networks to understand resource need, use, sharing and content. RESULTS: Understanding the COVID-19 vaccine was a process, not a single event using one resource. A visual resource had a place in facilitating conversations about vaccines between people with intellectual disabilities and carers. Differing perspectives were expressed regarding personal needs, existing awareness of vaccine programmes and communication preferences. Changes were suggested to improve the suggested storyline and relevance around COVID-19 restrictions changing. CONCLUSION: A visual resource may help conversations about the COVID-19 vaccine for people with intellectual disabilities.


Asunto(s)
COVID-19 , Discapacidad Intelectual , Adulto , Humanos , Vacunas contra la COVID-19 , Investigación Cualitativa , COVID-19/prevención & control , Vacunación
5.
J Med Syst ; 46(11): 75, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36195692

RESUMEN

Cognitive aids have been shown to facilitate adherence to evidence-based guidelines and improve technical performance of teams when managing simulated critical events. Few studies have explored the effect of cognitive aids on non-technical skills, such as teamwork and communication. The current study sought to explore the effects of different decision support tools (DST), a type of cognitive aid, on the technical and non-technical performance of teams. The current study represents a randomized, blinded, control trial of the effects of three versions of an electronic DST on team performance during multiple simulations of perioperative emergencies. The DSTs included a version with only technical information, a version with only non-technical information and a version with both technical and non-technical information. The technical performance of teams was improved when they used the technical DST and the combined technical and non-technical DST when compared to memory alone. The technical performance of teams was significantly worse when using the non-technical DST. All three versions of the DST had a negligible effect on the non-technical performance of teams. The technical performance of teams in the current study was affected by different versions of a DST, yet there was no effect on the teams' non-technical performance. The use of a DST, including those that focused on non-technical information, did not impact the non-technical performance of the teams.


Asunto(s)
Grupo de Atención al Paciente , Humanos , Competencia Clínica , Comunicación , Urgencias Médicas
6.
Environ Sci Technol ; 55(17): 11657-11666, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34423978

RESUMEN

Down-the-drain disposal of pharmaceuticals remains an overlooked and unrecognized source of environmental contamination that requires nontechnological "at-source" solutions. Monitoring of 31 pharmaceuticals over 7 days in five wastewater treatment plants (WWTPs) serving five cities in South-West UK revealed down-the-drain codisposal of six pharmaceuticals to three WWTPs (carbamazepine and propranolol in city A, sildenafil in city B, and diltiazem, capecitabine, and sertraline in city D), with a one-off record codisposal of estimated 253 pills = 40 g of carbamazepine and estimated 96 pills = 4 g of propranolol in city A accounting for their 10- and 3-fold respective increases in wastewater daily loads. Direct disposal of pharmaceuticals was found to affect the efficiency of wastewater treatment with much higher pharmaceutical removal (decrease in daily load) during "down-the-drain disposal" days. This is due to lack of conjugated glucuronide metabolites that are cleaved during "consumption-only" days, with the release of a parent pharmaceutical counterbalancing its removal. Higher removal of pharmaceuticals during down-the-drain disposal days reduced pharmaceutical loads reaching receiving environment, albeit with significant levels remaining. The estimated daily loads in receiving water downstream from a discharge point accounted for 13.8 ± 3.4 and 2.1 ± 0.2 g day-1 of carbamazepine and propranolol, respectively, during consumption-only days and peaked at 20.9 g day-1 (carbamazepine) and 4.6 g day-1 (propranolol) during down-the-drain disposal days. Actions are needed to reduce down-the-drain disposal of pharmaceuticals. Our recent work indicated that down-the-drain disposal of pharmaceuticals doubled since the last study in 2005, which may be due to the lack of information and messaging that informs people to dispose of unused medicines at pharmacies. Media campaigns that inform the public of how to safely dispose of medicines are key to improving rates of return and reducing pharmaceutical waste in the environment. The environment is a key motivator for returning unused medicines to a pharmacy and so messaging should highlight environmental risks associated with improper disposal.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Purificación del Agua , Monitoreo del Ambiente , Humanos , Ríos , Eliminación de Residuos Líquidos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
7.
Paediatr Anaesth ; 30(6): 676-682, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32271972

RESUMEN

BACKGROUND: Many cognitive aids are formatted in a step-by-step fashion with the intent that the aid will be accessed at the beginning of a critical event and that key behaviors will be performed in sequence. AIMS: We hypothesized that, during simulated pediatric intraoperative critical events, anesthesia clinicians may not use cognitive aids immediately after the onset of a critical event but instead access the aid only after first performing several key behaviors. MATERIALS AND METHODS: This manuscript is a re-analysis of previously published simulation data. The original study involved 89 clinicians participating in 143 pediatric intraoperative events divided into 6 types: arrhythmia, venous air embolus, hypoxemia, malignant hyperthermia, hypotension, and supraventricular tachycardia. For each trial involving cognitive aid use, we measured the time from event trigger to cognitive aid use, and the number and type of key behaviors performed by simulation participants prior to cognitive aid access. RESULTS: Cognitive aid use was sought in 66 of 93 trials where it was available. Sufficient data for this analysis were available in 65 trials. The average time from event trigger to first cognitive aid use was 258 seconds. In 62/65 trials (95%), the cognitive aid was accessed after at least one key behavior had already been performed. The time from event trigger to cognitive aid use varied by type of scenario (P = .03, df 5, adjusted H 12.78), with the shortest time for "supraventricular tachycardia" (90 [66,156] seconds (median [IQR]) and the longest time for "hypoxemia" (354 [192,492] seconds). CONCLUSION: In simulated critical events, anesthesia residents and student nurse anesthetists often consulted a cognitive aid only after first performing at least some key behaviors. Incorporating the possibility of delayed access into critical event cognitive aid design may facilitate the effectiveness of that aid.


Asunto(s)
Anestesia , Anestesiología , Niño , Cognición , Simulación por Computador , Humanos
8.
Anesth Analg ; 128(5): 993-998, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30379674

RESUMEN

BACKGROUND: Maternal mortality rate in developing countries is 20 times higher than in developed countries. Detailed reports surrounding maternal deaths have noted an association between substandard management during emergency events and death. In parallel with these findings, there is increasing evidence for cognitive aids as a means to prevent errors during perioperative crises. However, previously published findings are not directly applicable to cesarean delivery in low-income settings. Our hypothesis was that the use of obstetric anesthesia checklists in the management of high-fidelity simulated obstetrical emergency scenarios would improve adherence to best practice guidelines in low- and middle-income countries. METHODS: Accordingly, with input from East African health care professionals, we created a context-relevant obstetric anesthesia checklist for cesarean delivery. Second, clinical observations were performed to assess in a real-world setting. Third, a pilot testing of the cognitive aid was undertaken. RESULTS: Clinical observation data highlighted significant deficiencies in the management of obstetric emergencies. The use of the cesarean delivery checklist during simulations of peripartum hemorrhage and preeclampsia showed significant improvement in the percentage of completed actions (pretraining 23% ± 6% for preeclampsia and 22% ± 13% for peripartum hemorrhage, posttraining 75% ± 9% for preeclampsia, and 69% ± 9% for peripartum hemorrhage [P < .0001, both scenarios; data as mean ± standard deviation]). CONCLUSIONS: We developed, evaluated, and begun implementation of a context-relevant checklist for the management of obstetric crisis in low- and middle-income countries. We demonstrated not only the need for this tool in a real-world setting but also confirmed its potential efficacy through a pilot simulation study.


Asunto(s)
Anestesia Obstétrica/normas , Anestesiología/normas , Cesárea/normas , Lista de Verificación , Seguridad del Paciente , Anestesia Obstétrica/mortalidad , Trastornos del Conocimiento , Simulación por Computador , Países en Desarrollo , Urgencias Médicas , Femenino , Hemorragia , Humanos , Kenia , Mortalidad Materna , Errores Médicos/prevención & control , Obstetricia/normas , Periodo Periparto , Proyectos Piloto , Pobreza , Embarazo , Reproducibilidad de los Resultados
9.
Anesthesiology ; 127(3): 432-440, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28650415

RESUMEN

BACKGROUND: The success rates and related complications of various techniques for intubation in children with difficult airways remain unknown. The primary aim of this study is to compare the success rates of fiber-optic intubation via supraglottic airway to videolaryngoscopy in children with difficult airways. Our secondary aim is to compare the complication rates of these techniques. METHODS: Observational data were collected from 14 sites after management of difficult pediatric airways. Patient age, intubation technique, success per attempt, use of continuous ventilation, and complications were recorded for each case. First-attempt success and complications were compared in subjects managed with fiber-optic intubation via supraglottic airway and videolaryngoscopy. RESULTS: Fiber-optic intubation via supraglottic airway and videolaryngoscopy had similar first-attempt success rates (67 of 114, 59% vs. 404 of 786, 51%; odds ratio 1.35; 95% CI, 0.91 to 2.00; P = 0.16). In subjects less than 1 yr old, fiber-optic intubation via supraglottic airway was more successful on the first attempt than videolaryngoscopy (19 of 35, 54% vs. 79 of 220, 36%; odds ratio, 2.12; 95% CI, 1.04 to 4.31; P = 0.042). Complication rates were similar in the two groups (20 vs. 13%; P = 0.096). The incidence of hypoxemia was lower when continuous ventilation through the supraglottic airway was used throughout the fiber-optic intubation attempt. CONCLUSIONS: In this nonrandomized study, first-attempt success rates were similar for fiber-optic intubation via supraglottic airway and videolaryngoscopy. Fiber-optic intubation via supraglottic airway is associated with higher first-attempt success than videolaryngoscopy in infants with difficult airways. Continuous ventilation through the supraglottic airway during fiber-optic intubation attempts may lower the incidence of hypoxemia.


Asunto(s)
Tecnología de Fibra Óptica , Intubación Intratraqueal/instrumentación , Intubación Intratraqueal/métodos , Laringoscopía/instrumentación , Laringoscopía/métodos , Grabación de Cinta de Video , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Lactante , Laringoscopios , Masculino , Sistema de Registros/estadística & datos numéricos
10.
Anesth Analg ; 124(3): 900-907, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28079584

RESUMEN

Cognitive aids such as checklists are commonly used in modern operating rooms for routine processes, and the use of such aids may be even more important during critical events. The Quality and Safety Committee of the Society for Pediatric Anesthesia (SPA) has developed a set of critical-event checklists and cognitive aids designed for 3 purposes: (1) as a repository of the latest evidence-based and expert opinion-based information to guide response and management of critical events, (2) as a source of just-in-time information during critical events, and (3) as a method to facilitate a shared understanding of required actions among team members during a critical event. Committee members, who represented children's hospitals from across the nation, used the recent literature and established guidelines (where available) and incorporated the expertise of colleagues at their institutions to develop these checklists, which included relevant factors to consider and steps to take in response to critical events. Human factors principles were incorporated to enhance checklist usability, facilitate error-free accomplishment, and ensure a common approach to checklist layout, formatting, structure, and design.The checklists were made available in multiple formats: a PDF version for easy printing, a mobile application, and at some institutions, a Web-based application using the anesthesia information management system. After the checklists were created, training commenced, and plans for validation were begun. User training is essential for successful implementation and should ideally include explanation of the organization of the checklists; familiarization of users with the layout, structure, and formatting of the checklists; coaching in how to use the checklists in a team environment; reviewing of the items; and simulation of checklist use. Because of the rare and unpredictable nature of critical events, clinical trials that use crisis checklists are difficult to conduct; however, recent and future simulation studies with adult checklists provide a promising avenue for future validation of the SPA checklists. This article will review the developmental steps in producing the SPA crisis checklists, including creation of content, incorporation of human factors elements, and validation in simulation. Critical-events checklists have the potential to improve patient care during emergency events, and it is hoped that incorporating the elements presented in this article will aid in successful implementation of these essential cognitive aids.


Asunto(s)
Anestesia/métodos , Lista de Verificación/métodos , Cuidados Críticos/métodos , Técnicas de Apoyo para la Decisión , Pediatría/métodos , Sociedades Médicas , Anestesia/tendencias , Lista de Verificación/tendencias , Niño , Cognición , Cuidados Críticos/tendencias , Humanos , Quirófanos/métodos , Quirófanos/tendencias , Pediatría/tendencias , Sociedades Médicas/tendencias , Estados Unidos
11.
Mol Biol Evol ; 32(3): 661-73, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25468874

RESUMEN

Many studies of human populations have used the male-specific region of the Y chromosome (MSY) as a marker, but MSY sequence variants have traditionally been subject to ascertainment bias. Also, dating of haplogroups has relied on Y-specific short tandem repeats (STRs), involving problems of mutation rate choice, and possible long-term mutation saturation. Next-generation sequencing can ascertain single nucleotide polymorphisms (SNPs) in an unbiased way, leading to phylogenies in which branch-lengths are proportional to time, and allowing the times-to-most-recent-common-ancestor (TMRCAs) of nodes to be estimated directly. Here we describe the sequencing of 3.7 Mb of MSY in each of 448 human males at a mean coverage of 51×, yielding 13,261 high-confidence SNPs, 65.9% of which are previously unreported. The resulting phylogeny covers the majority of the known clades, provides date estimates of nodes, and constitutes a robust evolutionary framework for analyzing the history of other classes of mutation. Different clades within the tree show subtle but significant differences in branch lengths to the root. We also apply a set of 23 Y-STRs to the same samples, allowing SNP- and STR-based diversity and TMRCA estimates to be systematically compared. Ongoing purifying selection is suggested by our analysis of the phylogenetic distribution of nonsynonymous variants in 15 MSY single-copy genes.


Asunto(s)
Cromosomas Humanos Y/genética , Polimorfismo de Nucleótido Simple/genética , Evolución Molecular , Proyecto Mapa de Haplotipos , Humanos , Masculino , Filogenia , Análisis de Secuencia de ADN
12.
Curr Opin Crit Care ; 22(6): 527-532, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27748663

RESUMEN

PURPOSE OF REVIEW: The past decade has seen more advances in our understanding of fluid therapy than the preceding decades combined. What was once thought to be a relatively benign panacea is increasingly being recognized as a potent pharmacological and physiological intervention that may pose as much harm as benefit. RECENT FINDINGS: Recent studies have clearly indicated that the amount, type, and timing of fluid administration have profound effects on patient morbidity and outcomes. The practice of aggressive volume resuscitation for 'renal protection' and 'hemodynamic support' may in fact be contributing to end organ dysfunction. The practice of early goal-directed therapy for patients suffering from critical illness or undergoing surgery appears to offer no benefit over conventional therapy and may in fact be harmful. A new conceptual model for fluid resuscitation of critically ill patients has recently been developed and is explored here. SUMMARY: The practice of giving more fluid early and often is being replaced with new conceptual models of fluid resuscitation that suggest fluid therapy be 'personalized' to individual patient pathophysiology.


Asunto(s)
Lesión Renal Aguda/terapia , Enfermedad Crítica , Fluidoterapia , Resucitación , Humanos
13.
J Clin Monit Comput ; 30(3): 275-83, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26067401

RESUMEN

Cognitive aids (CA), including emergency manuals and checklists, are tools designed to assist users in prioritizing and performing complex tasks during time sensitive, high stress situations (Marshall in Anesth Analgesia 117(5):1162-1171, 2013; Marshall and Mehra in Anaesthesia 69(7):669-677, 2014). The society for pediatric anesthesia (SPA) has developed a series of emergency checklists tailored for use by pediatric perioperative teams that cover a wide range of intraoperative critical events (Shaffner et al. in Anesth Analgesia 117(4):960-979, 2013). In this study, we evaluated user preferences for a CA (SPA checklist) using two different presentation formats, paper and electronic, during management of simulated critical events. Anesthesia trainees managed the simulated critical events under one of three randomized conditions: (1) memory alone, (2) with a paper version of the CA, (3) with an electronic version of the CA. Following participation in the simulated critical events, participants were asked to complete a survey regarding their experience using the different versions of the CA. The percentage of favorable responses for each format of the CA was compared using a mixed effects proportional odds model. There were 143 simulated events managed by 89 anesthesia trainees. Approximately one out of three trainees (electronic 29 %, paper 30 %) assigned to use the CA chose not to use it and completed the scenario from memory alone. The survey was completed by 68 % of participants, 58 % of trainees preferred the paper version and 35 % preferred the electronic version. All survey responses that reached statistical significance favored the paper version. In this study, anesthesia trainees had a favorable opinion of the content and perceived clinical relevance of both versions of the CA. In both quantitative and qualitative analysis, the paper version of the CA was preferred over the electronic version by participants. Despite overall favorable responses to the CA, a sizeable number of participants chose not to use either version the CA during the crisis.


Asunto(s)
Lista de Verificación , Plásticos , Anestesia , Anestesiología , Niño , Cognición , Humanos
14.
J Am Chem Soc ; 137(16): 5256-9, 2015 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-25856143

RESUMEN

Here we show that the charge transfer (CT) absorption signal in bulk-heterojunction solar cell blends, measured by photothermal deflection spectroscopy, is directly proportional to the density of molecular donor:acceptor interfaces. Since the optical transitions from the ground state to the interfacial CT state are weakly allowed at photon energies below the optical gap of both the donor and acceptor, we can exploit the use of this sensitive linear absorption spectroscopy for such quantification. Moreover, we determine the absolute molar extinction coefficient of the CT transition for an archetypical polymer:fullerene interface. The latter is ∼100 times lower than the extinction coefficient of the donor chromophore involved, allowing us to experimentally estimate the transition dipole moment as 0.3 D and the electronic coupling between the ground and CT states to be on the order of 30 meV.

15.
Chemphyschem ; 16(6): 1295-304, 2015 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-25335767

RESUMEN

Broad spectral coverage over the solar spectrum is necessary for photovoltaic technologies and is a focus for organic solar cells. We report a series of small-molecule, nonfullerene electron acceptors containing the [(benzo[c][1,2,5]thiadiazol-4-yl)methylene]malononitrile unit as a high electron affinity component. The optoelectronic properties of these molecules were fine-tuned with the objective of attaining strong absorption at longer wavelengths by changing the low-ionization-potential moiety. The electron-accepting function of these materials was investigated with poly(3-n-hexylthiophene) (P3HT) as a standard electron donor. Significant photocurrent generation in the near infrared region, with an external quantum yield reaching as high as 22 % at 700 nm and an onset >800 nm was achieved. The results support efficient hole transfer to P3HT taking place after light absorption by the acceptor molecules. A Channel II-dominated power conversion efficiency of up to 1.5 % was, thus, achieved.

17.
J Am Chem Soc ; 136(14): 5237-40, 2014 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-24690032

RESUMEN

A facile ligand exchange method for dispersing Cu2ZnSnS4 (CZTS) nanocrystals (NCs) in environmentally benign polar solvents, such as ethanol or n-propanol, at high concentrations (up to 200 mg/mL) is demonstrated. This approach has been applied to CZTS nanocrystals synthesized via scalable, noninjection methods to formulate colloidally stable inks that are suitable for the solution processing of solar cell devices. Unlike other inks currently used to fabricate NC solar cells, the CZTS nanocrystal ink developed here circumvents the need for hydrazine, pyridine, or thiol coordinating solvents. By combining our polar CZTS inks with optimized selenization procedures, substrate CZTSSe solar cells have been successfully fabricated with device efficiencies of 7.7%.

18.
J Am Chem Soc ; 136(16): 6049-55, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24697300

RESUMEN

Extensive efforts have been made to develop novel conjugated polymers that give improved performance in organic photovoltaic devices. The use of polymers based on alternating electron-donating and electron-accepting units not only allows the frontier molecular orbitals to be tuned to maximize the open-circuit voltage of the devices but also controls the optical band gap to increase the number of photons absorbed and thus modifies the other critical device parameter-the short circuit current. In fact, varying the nonchromophoric components of a polymer is often secondary to the efforts to adjust the intermolecular aggregates and improve the charge-carrier mobility. Here, we introduce an approach to polymer synthesis that facilitates simultaneous control over both the structural and electronic properties of the polymers. Through the use of a tailored multicomponent acceptor-donor-acceptor (A-D-A) intermediate, polymers with the unique structure A-D1-A-D2 can be prepared. This approach enables variations in the donor fragment substituents such that control over both the polymer regiochemistry and solubility is possible. This control results in improved intermolecular π-stacking interactions and therefore enhanced charge-carrier mobility. Solar cells using the A-D1-A-D2 structural polymer show short-circuit current densities that are twice that of the simple, random analogue while still maintaining an identical open-circuit voltage. The key finding of this work is that polymers with an A-D1-A-D2 structure offer significant performance benefits over both regioregular and random A-D polymers. The chemical synthesis approach that enables the preparation of A-D1-A-D2 polymers therefore represents a promising new route to materials for high-efficiency organic photovoltaic devices.

19.
Anesth Analg ; 119(4): 932-938, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25076102

RESUMEN

BACKGROUND: Patients with long QT syndrome (LQTS) may experience a clinical spectrum of symptoms, ranging from asymptomatic, through presyncope, syncope, and aborted cardiac arrest, to sudden cardiac death. Arrhythmias in LQTS are often precipitated by autonomic changes. This patient population is believed to be at high risk for perioperative arrhythmia, specifically torsades de pointes (TdP), although this perception is largely based on limited literature that predates current anesthetic drugs and standards of perioperative monitoring. We present the largest multicenter review to date of anesthetic management in children with LQTS. METHODS: We conducted a multicentered retrospective chart review of perioperative management of children with clinically diagnosed LQTS, aged 18 years or younger, who received general anesthesia (GA) between January 2005 and January 2010. Data from 8 institutions were collated in an anonymized database. RESULTS: One hundred three patients with LQTS underwent a total of 158 episodes of GA. The median (interquartile range) age and weight of the patients at the time of GA was 9 (3-15) years and 30.3 (15.4-54) kg, respectively. Surgery was LQTS-related in 81 (51%) GA episodes (including pacemaker, implantable cardioverter-defibrillator, and loop recorder insertions and revisions and lead extractions) and incidental in 77 (49%). ß-blocker therapy was administered to 76% of patients on the day of surgery and 47% received sedative premedication. Nineteen percent of patients received total IV anesthesia, 30% received total inhaled anesthesia, and the remaining 51% received a combination. No patient received droperidol. There were 5 perioperative episodes of TdP, all in neonates or infants, all in surgery that was LQTS-related, and none of which was overtly attributable to anesthetic regimen. Thus the incidence (95% confidence interval) of perioperative TdP in incidental versus LQTS-related surgery was 0/77 (0%; 0%-5%) vs 5/81 (6.2%; 2%-14%). CONCLUSIONS: With optimized perioperative management, modern anesthesia for incidental surgery in patients with LQTS is safer than anecdotal case report literature might suggest. Our series suggests that the risk of perioperative TdP is concentrated in neonates and infants requiring urgent interventions after failed first-line management of LQTS.


Asunto(s)
Anestesia General/métodos , Síndrome de QT Prolongado/cirugía , Seguridad del Paciente , Atención Perioperativa/métodos , Adolescente , Anestesia General/efectos adversos , Anestesia General/normas , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Síndrome de QT Prolongado/diagnóstico , Síndrome de QT Prolongado/fisiopatología , Masculino , Seguridad del Paciente/normas , Atención Perioperativa/normas , Estudios Retrospectivos , Factores de Riesgo
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