Correlated Anion Disorder in Heteroanionic Cubic TiOF2.

Resolving anion configurations in heteroanionic materials is crucial for understanding and controlling their properties. For anion-disordered oxyfluorides, conventional Bragg diffraction cannot fully resolve the anionic structure, necessitating alternative structure determination methods. We have investigated the anionic structure of anion-disordered cubic (ReO3-type) TiOF2 using X-ray pair distribution function (PDF), 19F MAS NMR analysis, density functional theory (DFT), cluster expansion modeling, and genetic-algorithm structure prediction. Our computational data predict short-range anion ordering in TiOF2, characterized by predominant cis-[O2F4] titanium coordination, resulting in correlated anion disorder at longer ranges. To validate our predictions, we generated partially disordered supercells using genetic-algorithm structure prediction and computed simulated X-ray PDF data and 19F MAS NMR spectra, which we compared directly to experimental data. To construct our simulated 19F NMR spectra, we derived new transformation functions for mapping calculated magnetic shieldings to predicted magnetic chemical shifts in titanium (oxy)fluorides, obtained by fitting DFT-calculated magnetic shieldings to previously published experimental chemical shift data for TiF4. We find good agreement between our simulated and experimental data, which supports our computationally predicted structural model and demonstrates the effectiveness of complementary experimental and computational techniques in resolving anionic structure in anion-disordered oxyfluorides. From additional DFT calculations, we predict that increasing anion disorder makes lithium intercalation more favorable by, on average, up to 2 eV, highlighting the significant effect of variations in short-range order on the intercalation properties of anion-disordered materials.

What are the effects of drugs for nausea and vomiting prevention following general anesthesia? Summary and comments regarding a Cochrane Collaboration network meta-analysis

The aim of this special article is to summarize and discuss, from an anesthesia perspective, the network meta-analysis on drugs used for the prevention of postoperative nausea and vomiting after general anesthesia, in agreement with the Cochrane Colombia collaboration and within the framework of the Cochrane Corners strategy. Through the combination of indirect comparisons and based on the evidence, the use of aprepitant, ramosetron, granisetron, dexamethasone and ondansetron is recommended with a high degree of certainty for the reduction of postoperative nausea and vomiting.

Este artículo especial tiene el objetivo de resumir y discutir desde la perspectiva de la anestesiología, el metaanálisis en red sobre fármacos para prevenir náuseas y vómito posoperatorio luego de anestesia general, en acuerdo con la colaboración Cochrane Colombia y en el marco de la estrategia Cochrane Corners. Mediante la combinación de la evidencia y el uso de comparaciones indirectas, se ha recomendado con alto grado de certeza el uso de aprepitant, ramosetrón, granisetrón, dexametasona y ondansetrón para la reducción de náuseas y vómito posoperatorio.

Therapeutic efficacy of intravenous lidocaine infusion compared with thoracic epidural analgesia in major abdominal surgery: a noninferiority randomised clinical trial.

BACKGROUND: Open major abdominal surgery is one of the most risky surgical procedures for acute postoperative pain. Thoracic epidural analgesia (TEA) has been considered the standard analgesic approach. In different reports, lidocaine i.v. has been shown to have an analgesic efficacy comparable with TEA. We compared the analgesic efficacy of i.v. lidocaine with thoracic epidural analgesia using bupivacaine in patients undergoing major abdominal surgery. METHODS: In this noninferiority clinical trial, 210 patients were randomised to thoracic epidural bupivacaine with morphine or i.v. lidocaine. Dynamic pain at 24 h after surgery was measured using a numerical pain rating scale (NPR), and morphine consumption was also measured. A difference in i.v. the lidocaine-epidural bupivacaine NPR of ≤1 for dynamic pain was considered a noninferiority margin. RESULTS: The NPR for dynamic pain in the lidocaine group at 24 h was between 5.7 (1.8) and 5.2 (1.9) in the epidural group, with a difference of 0.53 (95% confidence interval 0.0-1.0). In the first 24 h, the average difference in morphine consumption was 1.8 mg between the i.v. lidocaine and epidural groups (95% confidence interval 1-3 mg). No differences were found in adverse events or complications associated with the procedures. CONCLUSIONS: Intravenous lidocaine is noninferior to thoracic epidural analgesia for acute postoperative pain control in major abdomial surgery at 24 h postoperatively. CLINICAL TRIALS REGISTRATION: NCT04017013.

Ultrasound identification of the cricothyroid membrane. Systematic review and meta-analysis

Introduction: The no-ventilation no-oxygenation situation is extremely important due to its high mortality. In these cases, open cricothyroidotomy is indicated. Around fifty percent of the difficulties are the result of inadequate identification of the cricothyroid membrane (CTM). Objective: To determine whether ultrasonography is superior to palpation to identify the CTM at the first attempt. Methods: A systematic review and a meta-analysis were conducted on the identification of the cricothyroid membrane versus palpation in Medline/Central and Embase. Clinical controlled trials and observational studies were included. Two authors independently and in duplicate selected the studies, assessed the biases and extracted the data; a random effects meta-analysis was successfully conducted for the correct identification of the CTM. The risk of bias was assessed and the certainty of the evidence was qualified. CRD42021223961. Results: 464 studies were included of which 15 met the eligibility criteria; 6 were clinical trials y 9 were observational. Ultrasound is superior to palpation in the detection of the CTM (RR 1.88, 95 % CI 1.05-3.36) according to the clinical trials, and it was also superior in observational studies (RR 1.76, 95 % CI 1.36-2.28). The association was preserved in the sensitivity analyses. Conclusions: Ultrasonography is superior to palpation for the correct identification of the TCM, though the certainty of the evidence is low. Further studies with better methodology are needed to improve both certainty and precision.

Introducción: La situación de no ventilación-no oxigenación es de gran importancia dada su elevada mortalidad. En dichos casos, la cricotiroidotomía abierta está indicada. Cerca de la mitad de las dificultades son causadas por inadecuada identificación de la membrana cricotiroidea (MCT). Objetivo: Determinar si la ultrasonografía es superior a la palpación para identificar la MCT al primer intento. Métodos: Se realizó una revisión sistemática y metaanálisis de identificación de membrana cricotiroidea versus palpación en Medline/Central y Embase. Se incluyeron ensayos clínicos controlados y estudios observacionales. Dos autores de manera independiente y por duplicado realizaron la selección de estudios, la evaluación de sesgos y la extracción de datos, se efectuó un metaanálisis de efectos aleatorios con el éxito de identificación correcta de la MCT. Se evaluó el riesgo de sesgos y se calificó la certeza de la evidencia. CRD42021223961. Resultados: Se incluyeron 464 estudios de los cuales 15 cumplieron criterios de elegibilidad, 6 fueron ensayos clínicos y 9 observacionales. La ecografía es superior a la palpación para detección de la MCT (RR 1,88, IC 95 % 1,05-3,36) según los ensayos clínicos y, similarmente, fue superior para los estudios observacionales (RR 1,76, IC 95 % 1,36-2,28); la asociación se conservó en los análisis de sensibilidad. Conclusiones: La ultrasonografía es superior a la palpación para detectar correctamente la MCT, aunque con baja certeza de la evidencia. Se requieren más estudios con mejor calidad metodo-lógica para mejorar la certeza y la precisión.

Uso perioperatorio de la ecografía de la vía aérea en un paciente con infección profunda del cuello. Reporte de caso / Perioperative use of airway ultrasound in a patient with a deep neck infection. Case Report

Introducción: las infecciones profundas del cuello son patologías complejas con gran potencial de complicaciones graves, que, debido a su ubicación pueden ser de difícil reconocimiento y manejo. Es de gran importancia realizar un diagnóstico asertivo y ofrecer el tratamiento adecuado para poder disminuir las complicaciones que se pudieran presentar. La ecografía es una ayuda diagnóstica cada vez más utilizada que nos puede ayudar a guiar nuestras conductas de manera rápida y efectiva. Caso clínico: presentamos un caso de un paciente con un absceso en cuello, en el que la utilización de la ecografía de manera intraoperatoria facilitó la toma de decisiones y evitó procedimientos invasivos innecesarios. Conclusiones: el Point of Care Ultrasound (PoCUS) es una forma rápida y práctica de resolver preguntas y facilitar la toma de decisiones objetivas en el entorno perioperatorio.

Introduction: Deep neck infections are a complex group of pathologies with great potential for serious complications due to their location. Therefore, recognition and management can be a challenge. To reduce the risk of complications it is extremely important to have an assertive diagnosis y and offer the proper treatment. An ultrasound is a diagnosis tool that is being used more often because it can help us guide our medical decisions in a quick and effective way. Clinical case: We present a case of a patient who had an intraoperative ultrasound which helped in the decision making and avoided any further invasive procedures. Conclusions: The Point of Care Ultrasound (PoCUS) is a quick and practical way to solve questions and facilitate objective decisions in the perioperative environment.

Erector Spinae Plane Block. A narrative review / Bloqueo del plano del músculo erector de la espina. Revisión narrativa de la literatura

Abstract The erector spinae plane (ESP) block is an interfascial block described in 2016 by Forero and collaborators, with wide clinical uses and benefits when it comes to analgesic control in different surgeries. This block consists of the application of local anesthetic (LA) in a deep plane over the transverse process, anterior to the erector spinae muscle in the anatomical site where dorsal and ventral branches of the spinal nerve roots are located. This review will cover its clinical uses according to different surgical models, the existing evidence and complications described to date.

Resumen El bloqueo del plano del músculo erector de la espina (ESP, por sus siglas en inglés) es un bloqueo interfascial descrito en 2016 por Forero y colaboradores, con amplios usos clínicos y beneficios en relación con el control analgésico de diferentes modelos quirúrgicos. Este consiste en la aplicación de anestésico local (AL) en un plano profundo sobre apófisis transversa anterior al músculo erector de la espina, sitio anatómico donde se encuentra la bifurcación de los ramos dorsal y ventral de las raíces nerviosas espinales. En esta revisión, se expondrán los usos clínicos según diferentes modelos quirúrgicos, la evidencia que existe de ellos y las complicaciones descritas hasta la actualidad.

Razonamiento clínico en medicina II: hacia una definición integradora / Clinical reasoning in medicine II: Towards an integrating definition

RESUMEN El entendimiento del razonamiento clínico es una necesidad para la investigación, la docencia y la práctica clínica. Los modelos teóricos subyacentes podrían agruparse en tres grandes ejes no excluyentes. El primero es denominado bayesiano informal según su estructura semejante al análisis de probabilidades condicionales. El segundo propone (desde las ciencias cognitivas) un razonamiento dual que es la suma de dos tipos de pensamientos: el tipo 1, rápido e intuitivo y, el tipo 2, hipotético-deductivo. El tercero, el conocimiento intersubjetivo que involucra la interacción del saber del paciente sobre su condición con el del médico, además, de hacer explícito el papel de la emoción. En esta segunda entrega se presenta una revisión narrativa de estas teorías para poder proponer una definición integradora, en la que se presenta al razonamiento clínico como un constructo complejo, iterativo y adaptativo.

SUMMARY Understanding clinical reasoning is a crucial for research, teaching, and daily clinical practice. Theoretical models could be grouped into three main non-exclusive axes. The first describes probability-based thinking, called informal Bayesian, because of its similarity to the conditional probability analysis structure. The second, from the cognitive sciences, describes reasoning as the sum of two types of thinking: type 1 (fast and intuitive) and type 2 (hypothetical-deductive). Finally, the third, intersubjective knowledge, which involves the interaction of the patient's knowledge about his condition with the doctor's knowledge and also makes explicit the role of emotion. In this second part, a narrative review of current theories is presented in order to propose an integrative definition, in which clinical reasoning is presented as a complex, iterative and adaptive construct.

Razonamiento clínico en medicina I: un recorrido histórico

El error médico es considerado un problema de salud pública que puede estar relacionado con fallas en la toma de decisiones de parte de un médico acerca del diagnóstico, el tratamiento o el pronóstico de un paciente, es decir, en el razonamiento médico. A pesar de su importancia, la comprensión sobre el razonamiento clínico ha sido heterogénea, con el uso de múltiples definiciones y modelos teóricos que se enfocan en distintos aspectos del procesamiento que hace el médico en la atención de un paciente. Esta diversidad conceptual puede explicarse por la influencia del contexto histórico. El cómo piensa el médico puede verse desde el pensamiento mágico en la Antigüedad, pasando por el racionalismo del Renacimiento y la aproximación científica moderna, hasta los modelos actuales del pensamiento dual y la estimación de probabilidades. Lo que parece ser constante es que existe una misión explicativa de saber qué le ocurre al paciente, aunque el fin último sea más comprender la experiencia del enfermo. En esta revisión narrativa se presenta esta evolución con una de línea de tiempo que resume las formas de concebir el razonamiento en medicina, según el contexto histórico.

SUMMARY Medical error is a public health problem, that may be related to failures in a doctor's decisionmaking about a patient's diagnosis, treatment, or prognosis, that is, in medical reasoning. Despite its importance, the understanding of clinical reasoning has been heterogeneous, with the use of multiple definitions and theoretical models, which focus on different aspects of the processing that physicians elaborate about taking care of a patient. This conceptual diversity can be explained by the influence of the historical context. How physicians think can be seen from magical thinking in Antiquity, through Renaissance rationalism and the modern scientific approach, to current models of dual thinking and probability estimation. What seems to be constant is that it has an explanatory mission of knowing what happens to the patient, although the ultimate goal is more to understand the patient's experience. In this narrative review, this evolution is presented with a timeline, which summarizes the ways of conceiving reasoning in medicine according to the historical context.

Differentiated thyroid cancer clinical trends in Quito, Ecuador / Tendencias clínicas del cáncer diferenciado de tiroides en Quito, Ecuador

Introduction.Thyroid cancer is currently the first most common cancer in women in Ecuador. This study aimed to assess the changes in clinical presentation and diagnosis of differentiated thyroid cancer at a third level hospital in Quito, Ecuador.Methods and Materials.This is a retrospective case series performed in three consecutive periods from 1990 to 2019 at a tertiary level hospital, in Quito, Ecuador. The clinical records of 875 patients who had been diagnosed and surgically treated for differentiated thyroid cancer were reviewed. Demographic, clinical, imaging, and pathological data were collected and analyzed.Results. Significant trends toward older age, higher educational level, less palpable primary tumors, less palpable neck nodes, less distant metastases, more ultrasound, tomography and cytology exams, smaller primary tumors, more stage I patients, and more histological variant description, were found. Introduction.Thyroid cancer is currently the first most common cancer in women in Ecuador. This study aimed to assess the changes in clinical presentation and diagnosis of differentiated thyroid cancer at a third level hospital in Quito, Ecuador.Methods and Materials.This is a retrospective case series performed in three consecutive periods from 1990 to 2019 at a tertiary level hospital, in Quito, Ecuador. The clinical records of 875 patients who had been diagnosed and surgically treated for differentiated thyroid cancer were reviewed. Demographic, clinical, imaging, and pathological data were collected and analyzed.Results. Significant trends toward older age, higher educational level, less palpable primary tumors, less palpable neck nodes, less distant metastases, more ultrasound, tomography and cytology exams, smaller primary tumors, more stage I patients, and more histological variant description, were found.

Introducción. El cáncer de tiroides es actualmente el cáncer más frecuente en la mujer en Ecuador. El presente estudio ha tenido como objetivo evaluar los cambios en la presentación clínica y el diagnóstico del cáncer diferenciado de tiroides en un hospital de tercer nivel de Quito, Ecuador. Material y Métodos. El presente es un estudio retrospectivo de casos realizado en tres períodos consecutivos desde 1990 a 2019 en un hospital del tercer nivel en Quito, Ecuador. Los expedientes clínicos de 875 pacientes tratados quirúrgicamente por un cáncer diferenciado de tiroides fueron revisados. Los datos demográficos, clínicos, de imagen y patología fueron extraídos y analizados. Resultados. Se encontraron tendencias significativas hacia una edad más avanzada, nivel educativo más alto, menos tumores palpables, menos adenopatías regionales palpables, menos metástasis a distancia, más exámenes de ultrasonido y tomografía, más estudios de citología, más tumores pequeños y pacientes con estadío I y más descripciones de las variantes histológicas. Conclusiones. El cáncer de tiroides no sólo que ha aumentado continuamente en su frecuencia en los años recientes, sino que la presentación clínica, el manejo diagnóstico y terapéutico ha cambiado significativamente en las tres últimas décadas.

Ultrasound-guided superior laryngeal nerve block -A description of the technique / Bloqueo de nervio laríngeo superior guiado por ecografia. Descripción de la técnica

Abstract Complications in airway management remain a common cause of anesthesia-associated mortality. When a patient is considered with anticipated difficult airway, the management depends on several variables, however, at present, the standard of management continues to be the patient awake approach. In scenarios of acute upper airway obstruction, the only way to guarantee adequate ventilation is to obtain a translaryngeal or transtracheal access, for which, it is necessary to use local anesthesia and grade I / II sedation, avoiding loss of spontaneous ventilation. For this purpose, we propose ultrasound-guided superior laryngeal nerve block, in order to standardize an ultrasound landmark that is reproduceable, with a high success rate, which allows limiting complications related to regional anatomic techniques and thus facilitating the securing of the airway in these patients.

Resumen Las complicaciones en el manejo de la vía aérea siguen siendo una causa frecuente de mortalidad relacionada con anestesia. Cuando un paciente se considera con vía aérea difícil anticipada, el manejo depende de diversas variables, sin embargo, en la actualidad, el estándar de manejo sigue siendo el abordaje con paciente despierto. En escenarios de obstrucción aguda de la vía aérea superior, la única forma de garantizar una adecuada ventilación es obtener un acceso translaríngeo o transtraqueal, para lo cual, es necesario el uso de anestesia local y de sedación grado I/II evitando la pérdida de ventilación espontánea. Con este propósito, planteamos el bloqueo del nervio laríngeo superior guiado por ultrasonografía, con el fin de estandarizar una referencia ecográfica reproducible, con alto índice de éxito, la cual permita limitar complicaciones relacionadas con las técnicas regionales anatómicas y así facilitar el aseguramiento de la vía aérea en estos pacientes.

Successful rescue with videolaryngoscopy after failed fibroscopy in anticipated difficult airway: case series / Rescate exitoso con videolaringoscopia luego de fibroscopia fallida en vía aérea difícil anticipada: serie de casos

Abstract Introduction: In the management of the anticipated difficult airway (DA), awake intubation is the strategy of choice. In this context, flexible fibroscopy is the tool most widely used as the first choice. However, there is always the rare case where it may fail. Important findings: Six successful rescue cases using videolaryngoscopy following failed fibroscopy in patients with anticipated DA, and 1 case of rescued extubation of an airway previously secured with fiberoptic bronchoscopy. Conclusion: Videolaringoscopy may be an adequate tool to use as a backup plan for the management of an anticipated DA.

Resumen Introducción: En el manejo de vía aérea difícil anticipada la estrategia de elección es la intubación con el paciente despierto. En este contexto, la fibroscopia flexible es la herramienta más utilizada como plan A; sin embargo, en raras ocasiones puede fallar. Hallazgos importantes: Se presentan seis casos de rescates exitosos con videolaringoscopia luego de fibroscopia fallida en pacientes con vía aérea difícil anticipada, y un caso de rescate de extubación de vía aérea asegurada previamente con fibrobroncoscopio. Conclusión: La videolaringoscopia puede ser una adecuada herramienta como plan B para el manejo de la vía aérea difícil anticipada.

Impact of Anion Vacancies on the Local and Electronic Structures of Iron-Based Oxyfluoride Electrodes.

The properties of crystalline solids can be significantly modified by deliberately introducing point defects. Understanding these effects, however, requires understanding the changes in geometry and electronic structure of the host material. Here we report the effect of forming anion vacancies, via dehydroxylation, in a hexagonal tungsten-bronze-structured iron oxyfluoride, which has potential use as a lithium-ion battery cathode. Our combined pair distribution function and density functional theory analysis indicates that oxygen vacancy formation is accompanied by spontaneous rearrangement of fluorine anions and vacancies, producing dual pyramidal (FeF4)-O-(FeF4) structural units containing 5-fold-coordinated Fe atoms. The addition of lattice oxygen introduces new electronic states above the top of the valence band, with a corresponding reduction in the optical band gap from 4.05 to 2.05 eV. This band gap reduction relative to the FeF3 parent material is correlated with a significant improvement in lithium insertion capability relative to a defect-free compound.

Intubación traqueal a ciegas con dispositivo supraglótico Air-Q: serie prospectiva de casos en pediatría / Blind tracheal intubation with Air-Q supraglottis device: prospective case series in pediatrics

Abstract Introduction: Airway management in children is one of the challenges faced by physicians in the different care settings. Unlike the adult population, there is no standard-of-reference device for blind intubation in pediatrics. Our group has already conducted a case series study using the I-Gel device for this purpose, but with no acceptable rates of blind intubation. As part of our search for an appropriate device for this purpose, we examined the use of the Air-Q which comes in pediatric sizes but lacks studies for blind intubation in this population. Objective: The main objective of this study was to assess the percentage of successful blind tracheal intubations through the Air-Q supraglottic device. Materials and methods: Prospective sample of 45 pediatric patients weighing between 7 and 50 kg. Besides assessing the percentage of successful blind tracheal intubations, sealing pressures, and fiberoptic visualization through the device were also evaluated and reported, together with the complications associated with the procedure. Results and conclusion: The overall percentage of blind intubation through the Air-Q mask in this study was 55.5%, found to be not acceptable to warrant a recommendation of use for blind intubation; on the other hand, ideal fiberoptic visualiza tion was acceptable, making this method advisable for fiberoptic-guided intubation through the supraglotting device.

Resumen Introducción: El manejo de la vía aérea en el niño hace parte de los desafíos a los cuales debe enfrentarse el médico en los diferentes servicios de atención. A diferencia de la población adulta, en pediatría no existe un dispositivo estándar de referencia para la intubación a ciegas; nuestro grupo ya realizo una serie de casos con el dispositivo I-gel para este propósito, el cual no mostró tasas aceptables de intubación a ciegas; buscando un dispositivo idóneo para este fin, se plantea el dispositivo Air-Q el cual viene en tamaños pediátricos y no tiene estudios en esta población para intubación a ciegas. Objetivo: El objetivo principal de este estudio fue evaluar el porcentaje de éxito en la intubación traqueal a ciegas a través del dispositivo supraglótico Air-Q. Materiales y métodos: Se recogió una muestra prospectiva en una población pediátrica de 45 pacientes con peso entre 7 y 50Kg, además de evaluar el porcentaje de éxito de la intubación traqueal a ciegas, se evaluó la presión de sello, visión fibroscópica a través del dispositivo y se reportaron las complicaciones asociadas al procedimiento. Resultados y conclusiones: El porcentaje global de intuba ción a ciegas a través de la máscara Air-Q en este estudio fue del 55,5%, encontrándolo como un porcentaje no aceptable para recomendar la intubación a ciegas a través de este dispositivo; por otra parte la visión fibroscópica ideal fue aceptable, pudiéndose aconsejar como método para guiar la intubación fibroscópica a través de dispositivo supraglótico.

Ion-ion correlations across and between electrified graphene layers.

When an ionic liquid adsorbs onto a porous electrode, its ionic arrangement is deeply modified due to a screening of the Coulombic interactions by the metallic surface and by the confinement imposed upon it by the electrode's morphology. In particular, ions of the same charge can approach at close contact, leading to the formation of a superionic state. The impact of an electrified surface placed between two liquid phases is much less understood. Here we simulate a full supercapacitor made of the 1-butyl-3-methylimidazolium hexafluorophosphate and nanoporous graphene electrodes, with varying distances between the graphene sheets. The electrodes are held at constant potential by allowing the carbon charges to fluctuate. Under strong confinement conditions, we show that ions of the same charge tend to adsorb in front of each other across the graphene plane. These correlations are allowed by the formation of a highly localized image charge on the carbon atoms between the ions. They are suppressed in larger pores, when the liquid adopts a bilayer structure between the graphene sheets. These effects are qualitatively similar to the recent templating effects which have been reported during the growth of nanocrystals on a graphene substrate.

Carcinoma cutáneo de células de Merkel, a propósito de un caso y revisión de la literatura / Cutaneous carcinoma of merkel cells, purpose of a case and review of literature

El carcinoma de células de Merkel o también llamado carcinoma neuroendocrino cutáneo es una neoplasia muy rara y agresiva. Se caracteriza por su tendencia a la recurrencia, diseminación ganglionar y metástasis a gran distancia. Se presenta el caso de un paciente masculino de 88 años de edad, con antecedente de carcinoma baso celular en región dorsal, que presenta hace 3 meses una tumoración cutánea en tobillo derecho de gran tamaño, que produce metástasis ganglionar a distancia, el estudio de inmunohistoquímica revela que se trata de un carcinoma neuroendocrino cutáneo, se realiza excéresis del mismo con bordes histológicos negativos, pero a los pocos meses recidiva por lo que se realiza cirugía más profunda y se acompaña de quimioterapia. Se pone énfasis en lo agresivo y tendencia a la recidiva de esta rara enfermedad que podría pasar desapercibida en centros de menor complejidad.

The Merkel cell carcinoma, also known as cutaneous neuroendocrine carcinoma, is a very rare and aggressive neoplasm. It is characterized by its tendency to recurrence, lymph node dissemination and distant metastasis. We present the case of a 88-year-old male patient with a history of basal cell carcinoma in the dorsal region, who presented a large right cutaneous tumor in the right ankle 3 months ago, which produces distant lymph node metastasis. The immunohistochemical study reveals that it is a cutaneous neuroendocrine carcinoma, exeresis is performed with negative histological edges, but after a few months it relapses, so a deeper surgery is performed and it is accompanied by chemotherapy. Emphasis is placed on the aggressiveness and tendency to recurrence of this rare disease that could go unnoticed in centers of less complexity.

Intubación traqueal con dispositivo supraglótico I-gel en pacientes pediátricos: Serie de casos prospectiva / Tracheal intubation with I-gel supraglottic device in pediatric patients: a prospective case series

Abstract Introduction: Currently, there are no devices showing an acceptable success rate in blind intubation in pediatrics. Objectives: The purpose of this particular series of cases is to identify the percentage of successful blind intubations using the Igel laryngeal mask in children between 2 and 35 kg of body weight, in addition to evaluating seal pressure, fiber optics vision through the device, and reporting the occurrence of complications. Materials and methods: A prospective case series in pediatrics; patients from 2 to 35 kg. Results: According to our study, the overall percentage of blind intubation was 23%, while the percentages of ideal and low vision to facilitate the insertion of the bronchoscope into the airway, and then inserting a tracheal tube through the fiber optics was 70%. Conclusion: We feel that the supraglottic I-gel is not the appropriate device for blind intubation; however, it is an acceptable recommendation to conduct fiber optics intubation.

Resumen Introducción: No hay un dispositivo en la actualidad que demuestre apropiado porcentaje de éxito de intubación a ciegas en pediatría. Objetivos: El propósito de esta serie de casos es conocer el porcentaje de éxito de intubación a ciegas a través de la máscara laríngea I-gel en niños pesando entre 2 y 35 kilos, además evaluar la presión de sello, la visión fibroscópica a través del dispositivo y reportar la aparición de complicaciones. Materiales y Métodos: Serie prospectiva de casos en pediatría, en pacientes de 2 a 35 kilos. Resultados: En nuestro estudio el porcentaje global de intubación a ciegas fue del 23%, el porcentaje de visión ideal y visión baja, que permiten fácil introducción del broncoscopio en la via aérea y luego a través del fibroscopio introducir un tubo traqueal, fue de un 70%. Conclusiones: Consideramos que el I-gel supraglótico no es un dispositivo adecuado para intubación a ciegas. Sin embargo, tiene un valor aceptable para recomendar realizar intubación fibro-óptica a través del dispositivo supraglótico I-gel. Results: According to our study, the overall percentage of blind intubation was 23%, while the percentages of ideal and low vision to facilitate the insertion of the bronchoscope into the airway, and then inserting a tracheal tube through the fiber optics was 70%. Conclusions: We feel that the supraglottic I-gel is not the appropriate device for blind intubation; however, it is an acceptable recommendation to conduct fiber optics intubation.

Confinement Effects on an Electron Transfer Reaction in Nanoporous Carbon Electrodes.

Nanoconfinement generally leads to a drastic effect on the physical and chemical properties of ionic liquids. Here we investigate how the electrochemical reactivity in such media may be impacted inside of nanoporous carbon electrodes. To this end, we study a simple electron transfer reaction using molecular dynamics simulations. The electrodes are held at constant electric potential by allowing the atomic charges on the carbon atoms to fluctuate. We show that the Fe3+/Fe2+ couple dissolved in an ionic liquid exhibits a deviation with respect to Marcus theory. This behavior is rationalized by the stabilization of a solvation state of the Fe3+ cation in the disordered nanoporous electrode that is not observed in the bulk. The simulation results are fitted with a recently proposed two solvation state model, which allows us to estimate the effect of such a deviation on the kinetics of electron transfer inside of nanoporous electrodes.

Sparse Cyclic Excitations Explain the Low Ionic Conductivity of Stoichiometric Li_{7}La_{3}Zr_{2}O_{12}.

We have performed long time scale molecular dynamics simulations of the cubic and tetragonal phases of the solid lithium-ion electrolyte Li_{7}La_{3}Zr_{2}O_{12} (LLZO), using a first-principles parametrized interatomic potential. Collective lithium transport was analyzed by identifying dynamical excitations: persistent ion displacements over distances comparable to the separation between lithium sites, and stringlike clusters of ions that undergo cooperative motion. We find that dynamical excitations in c-LLZO (cubic) are frequent, with participating lithium numbers following an exponential distribution, mirroring the dynamics of fragile glasses. In contrast, excitations in t-LLZO (tetragonal) are both temporally and spatially sparse, consisting preferentially of highly concerted lithium motion around closed loops. This qualitative difference is explained as a consequence of lithium ordering in t-LLZO and provides a mechanistic basis for the much lower ionic conductivity of t-LLZO compared to c-LLZO.