Impact of defibrillation technique on the rheological, thermo-mechanical, and nutritional properties of nanosuspensions produced from multiple fractions of pinhão seed (Araucaria angustifolia (Bertol.) Kuntze).

This work aimed to evaluate the influence of the mechanical defibrillation technique on the pinhão nanosuspensions production obtained from the whole pinhão, its coat, and almond. The nanosuspensions were characterized concerning their composition, morphology, thermal stability, rheological behavior, compound profiling, and cytotoxicity. The results revealed a significant fiber content in pinhão coat nanosuspension (63.12 ± 0.52 %) and non-fiber carbohydrates in whole pinhão (59.00 ± 0.13 %) and almond (74.39 ± 0.23 %) nanosuspensions. The defibrillation process led to micro/nano-sized fibers in pinhão coat nanosuspensions and small-size starch granules in almond nanosuspensions. The nanosuspensions containing pinhão coat exhibited a gel-like behavior, while almond nanosuspensions displayed liquid-like characteristics. Pinhão coat nanosuspensions presented a significant content of flavonoids and phytosterols, whereas almond-based nanosuspensions contained substantial sugar amounts. No cytotoxicity was observed at the concentrations evaluated. These findings demonstrated that the defibrillation technique impacted the properties of pinhão constituents, allowing their application in new product development.

Endoglucanase pretreatment aids in isolating tailored-cellulose nanofibrils combining energy saving and high-performance packaging.

Cellulose nanofibrils (CNFs) have emerged as a potential alternative to synthetic polymers in packaging applications owing to their oxygen and grease barrier performance, as well as their strong mechanical properties. However, the performance of CNF films relies on the inherent characteristics of fibers, which undergo changes during the CNF isolation process. Understanding these variations in characteristics during CNF isolation is crucial for tailoring CNF film properties to achieve optimum performance in packaging applications. In this study, CNFs were isolated by endoglucanase-assisted mechanical ultra-refining. The alterations in the intrinsic characteristics of CNFs and their impact on CNF films were systematically investigated by considering the degree of defibrillation, enzyme loading, and reaction time through a design of experiments. Enzyme loading had a significant influence on the crystallinity index, crystallite size, surface area, and viscosity. Meanwhile, the degree of defibrillation greatly affected the aspect ratio, degree of polymerization, and particle size. CNF films prepared from CNFs isolated under two optimized scenarios (casting and coating applications) exhibited remarkable properties, including high thermal stability (approximately 300 °C), high tensile strength (104 - 113 MPa), excellent oil resistance (kit n°12), and low oxygen transmission rate (1.00 - 3.17 cc·m-2.day-1). Therefore, endoglucanase pretreatment can aid in obtaining CNFs with lower energy consumption, resulting in films that possess higher transmittance, superior barrier performance, and reduced surface wettability compared to control samples without enzymatic pretreatment and other unmodified CNF films reported in the literature, all while maintaining mechanical and thermal performance without significant loss.

Cardio protected areas in Mexico.

Sudden cardiac death (SCD) remains a major public health problem. Fortunately, with timely access to early defibrillation and high-quality cardiopulmonary resuscitation, an improvement in survival of victims of sudden death has been demonstrated. Efforts made in different countries to create programs for access to public defibrillation have shown great benefits in counteracting mortality associated with this type of event. Hence, we need more programs (such as cardio protected environments) and changes in public health policies. The objective of this work is to raise awareness among the population and decision makers, of importance establishing this type of programs in our country since there continues to be high mortality associated with SCD in our countrymen.

La muerte súbita cardíaca es todavía un problema importante de salud pública. Por fortuna, con un acceso oportuno a una desfibrilación temprana y una reanimación cardiopulmonar de alta calidad, se ha demostrado una mejoría en la sobrevida de las víctimas de muerte súbita. Los esfuerzos realizados en deferentes países para crear programas de acceso a la desfibrilación pública han mostrado grandes beneficios en contrarrestar la mortalidad relacionada con este tipo de episodios. Se necesitan más programas (como espacios cardioprotegidos) y cambios en las políticas de salud pública. El objetivo de este trabajo es poder concientizar a la población y a los tomadores de decisiones de la importancia de establecer este tipo de programas en el país, ya que aún existe una alta mortalidad relacionada con la muerte cardíaca súbita.

Double Defibrillation for Refractory In- and Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis.

BACKGROUND: Double/dual defibrillation (DD) has been proposed as an alternative treatment for refractory ventricular fibrillation (VF). This topic has been poorly researched and data on survival rates are limited. OBJECTIVE: This systematic review and meta-analysis evaluates whether DD improves outcomes among patients with refractory VF in- and out-of-hospital cardiac arrest compared with standard defibrillation. METHODS: A literature search was conducted on July 20, 2019 using MEDLINE via PubMed, Embase, Scopus, and the Cochrane Database of Systematic Reviews. We gave all results as a pooled odds ratio (OR) and 95% confidence interval (CI). Heterogeneity was assessed by calculating the I2 statistic and was deemed significant for a p value of < 0.10 or I2 ≥ 50%. The quality of evidence was evaluated according to Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines. RESULTS: We included 27 records, of which 4 cohort studies totaling 1061 patients were included in the quantitative analysis. Of these, 20.5% (n = 217) received the intervention. DD had no effect on return of spontaneous circulation (OR 0.68; 95% CI 0.44-1.04; I2 = 41%, p = 0.08) (GRADE: Very low), survival to admission (OR 0.77; 95% CI 0.51-1.17; I2 = 18%, p = 0.22) (GRADE: Very low), or survival to discharge (OR 0.66; 95% CI 0.38-1.15; I2 = 0%, p = 0.14) (GRADE: Very low). CONCLUSIONS: DD did not improve any outcomes of interest. Therefore, it is imperative that a well-designed study in this area be conducted. Ideally, conducting a randomized controlled trial in this population should be attempted to obtain a higher level of scientific evidence.

Paro cardiorrespiratorio por electrocución tratado con éxito extrahospitalariamente / Cardiorespiratory Arrest Caused by Electrocution Successfully Treated in an Extra-Hospital Situation / Parada cardiorrespiratória por eletrocussão tratada com sucesso de maneira extra-hospitalar

Resumen Introducción: son pocos los datos documentados sobre los resultados de la reanimación cardiopulmonar en el paro cardiorrespiratorio extrahospitalario por causa de electrocución. El paro cardiorrespiratorio se produce cuando una descarga eléctrica interrumpe de forma abrupta la actividad eléctrica normal del corazón, lo que genera una electrocución y una alteración en los movimientos cardiacos y, por consiguiente, bombeo anormal de sangre y oxígeno a los tejidos. Ello constituye una emergencia clínica que puede ocasionar nefastas consecuencias de no tomarse medidas enérgicas e inmediatas. Presentación del caso: hombre con paro cardiorrespiratorio producido por electrocución y manejado en un ámbito extra-hospitalario, quien respondió con éxito a las maniobras aplicadas. Personal técnico y de salud iniciaron precozmente la reanimación cardiopulmonar y luego fue reforzada por personal médico, que aplicó desflbrilación en dos ocasiones con desflbrilador externo automático (DEA). Con ello se logró recuperar los signos vitales del paciente y trasladarlo a un centro asistencial para continuar su manejo intrahospitalario. Conclusión: la realización de una reanimación precoz y la desfibrilación de pacientes electrocutados, así como las medidas encaminadas a la protección del cerebro, son la norma prioritaria en la asistencia pre-hospitalaria de estos pacientes, quienes son potencialmente recuperables. Por tal razón, es importante que la comunidad, en general, esté preparada y que el personal de salud se reentrene en soporte vital básico, que incluye el manejo del DEA para dar oportunidad de sobrevivir a personas que sufran un paro cardiorrespiratorio extrahospitalario.

Abstract Introduction: There are few the documented data about the cardiopulmonary resuscitation results in the cardiorespiratory arrest extra-hospital due to the electrocution. The cardiorespiratory arrest occurs when the heart's normal electrical activity is abruptly interrupted by electric shocks generated by electrocution, causing the disturbance in the cardiac movements and, consequently, abnormal pumping of blood and oxygen to the tissues. The cardiorespiratory arrest due to electrocution is one clinic emergency that can cause disastrous consequences, if energetic measures are not taken immediately. Case presentation: A man with cardiorespiratory arrest produced by electrocution and managed in an extra-hospital area, who responded successfully to the maneuvers applied. The cardiopulmonary resus-citation maneuvers were precociously started by the health technical staff; next, reinforced by medical it, applying the defibrillation on two occasions, with external automatic defibrillator (AED), recovering the patient's vital signs and allowing his transfer to a healthcare center to continue in-hospital management. Conclusion: The performing of early resuscitation and defibrillation of electrocuted patients, as well as the measures aimed at protecting the brain, are the priority rules in the pre-hospital scene of these patients, who are potentially recoverable. For this reason, it is important that the community, in general, be ready, and the health staff gets trained in basic vital support that includes the management of AED to give the opportunity of surviving to people that suffer a cardiorespiratory arrest.

Resumo Introdução: são poucos os dados documentados sobre os resultados da reanimação cardiopulmonar na parada cardiorrespiratória extra-hospitalar por causa de eletrocussão. A parada cardiorrespiratória se produz quando a atividade elétrica normal do coração é interrompida abruptamente pela descarga elétrica que gera a eletrocussão causando alterado nos movimentos cardíacos e por conseguinte bombeamento anormal de sangue e oxigeno aos tecidos. A parada cardiorrespiratória causada por eletrocussão é uma emergência clínica que pode ocasionar nefastas consequências, de não tomar medidas enérgicas e imediatas. Apresentação do caso: homem com parada cardiorrespiratória, produzida por eletrocussão e manejado em um âmbito extra-hospitalar, quem respondeu com sucesso ás manobras aplicadas. A rearrumação cardiopulmonar foi iniciada precocemente por pessoal técnico de saúde, posteriormente reforjadas por pessoal médico, aplicando a desfibrilação em duas ocasiões, com desfibrilador automático externo (DEA), recuperando os signos vitais do paciente e permitindo seu traslado e um centro assistencial para continuar manejo intra-hospitalar. Conclusão: a realizado de uma rearrumação precoce e desfibrilação de pacientes eletrocutados, assim como as medidas encaminhadas á proteção do cérebro, são a norma prioritária na assistência pré-hospitalar destes pacientes, os quais são potencialmente recuperáveis; por esta razão é importante que a comunidade, em geral, esteja preparada e que o pessoal de saúde se retreine em suporte vital básico que inclua o manejo do DEA para dar oportunidade de sobrevida a pessoas que sofram uma parada cardiorrespiratória extra-hospitalar.

Prehospital Double Defibrillation for Refractory Ventricular Fibrillation: A Scoping Review Protocol.

Double defibrillation (DD) has been proposed as an alternative treatment for patients with refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT) out-of-hospital cardiac arrest (OHCA) nonresponsive to the best current standard of care. Treatment results are promising, but the efficacy and safety of the procedure remain unclear. Currently, there is a paucity of evidence in the literature on DD suggesting the optimal strategy for treating this challenging patient population. Thus, we aim to perform a scoping review to explore the current literature addressing resuscitative parameters, survival rates, and neurological outcomes in refractory VF/pVT OHCA patients treated with DD as well as to identify gaps in the literature that may require further research. Here, we discuss the anticipated study protocol.

Reanimación cardiopulmonar en pacientes con enfermedad por COVID-19 en el ambiente hospitalario / Cardiopulmonary resuscitation in patients with COVID-19 in the hospital environment

Resumen: La pandemia COVID-19 nos ha obligado a replantearnos la manera en la que practicamos algunos aspectos de la medicina. La reanimación cardiopulmonar es una práctica que genera partículas en aerosol provenientes de la vía aérea, lo cual incrementa el riesgo de contagio por SARS-CoV-2. En esta revisión se consultan las recomendaciones internacionales sobre el tema, se definen momentos de alto riesgo y se establecen recomendaciones sobre compresiones, ventilación, terapia eléctrica e incluso farmacológica en pacientes con paro cardíaco y con diagnóstico de COVID-19, buscando no sólo el bienestar del paciente, sino también la seguridad del personal de salud.

Abstract: The COVID-19 pandemic has forced us to rethink the way we practice some aspects of medicine. Cardiopulmonary resuscitation is a practice that generates aerosol particles from the airway, which increases the risk of SARS-CoV-2 infection. In this review, the international recommendations on the subject are consulted, high-risk moments are defined and recommendations are established on compressions, ventilation, electrical therapy and even pharmacology in patients with cardiac arrest and with a diagnosis of COVID-19, seeking not only the well-being of the patient, but also the safety of health personnel.

Cardio protected areas in Mexico / Áreas cardioprotegidas en México

Abstract Sudden cardiac death (SCD) remains a major public health problem. Fortunately, with timely access to early defibrillation and high-quality cardiopulmonary resuscitation, an improvement in survival of victims of sudden death has been demonstrated. Efforts made in different countries to create programs for access to public defibrillation have shown great benefits in counteracting mortality associated with this type of event. Hence, we need more programs (such as cardio protected environments) and changes in public health policies. The objective of this work is to raise awareness among the population and decision makers, of importance establishing this type of programs in our country since there continues to be high mortality associated with SCD in our countrymen.

Resumen La muerte súbita cardíaca es todavía un problema importante de salud pública. Por fortuna, con un acceso oportuno a una desfibrilación temprana y una reanimación cardiopulmonar de alta calidad, se ha demostrado una mejoría en la sobrevida de las víctimas de muerte súbita. Los esfuerzos realizados en deferentes países para crear programas de acceso a la desfibrilación pública han mostrado grandes beneficios en contrarrestar la mortalidad relacionada con este tipo de episodios. Se necesitan más programas (como espacios cardioprotegidos) y cambios en las políticas de salud pública. El objetivo de este trabajo es poder concientizar a la población y a los tomadores de decisiones de la importancia de establecer este tipo de programas en el país, ya que aún existe una alta mortalidad relacionada con la muerte cardíaca súbita.

Cardio protected areas in Mexico.

Sudden cardiac death (SCD) remains a major public health problem. Fortunately, with timely access to early defibrillation and high-quality cardiopulmonary resuscitation, an improvement in survival of victims of sudden death has been demonstrated. Efforts made in different countries to create programs for access to public defibrillation have shown great benefits in counteracting mortality associated with this type of event. Hence, we need more programs (such as cardio protected environments) and changes in public health policies. The objective of this work is to raise awareness among the population and decision makers, of importance establishing this type of programs in our country since there continues to be high mortality associated with SCD in our countrymen.

La muerte súbita cardíaca es todavía un problema importante de salud pública. Por fortuna, con un acceso oportuno a una desfibrilación temprana y una reanimación cardiopulmonar de alta calidad, se ha demostrado una mejoría en la sobrevida de las víctimas de muerte súbita. Los esfuerzos realizados en deferentes países para crear programas de acceso a la desfibrilación pública han mostrado grandes beneficios en contrarrestar la mortalidad relacionada con este tipo de episodios. Se necesitan más programas (como espacios cardioprotegidos) y cambios en las políticas de salud pública. El objetivo de este trabajo es poder concientizar a la población y a los tomadores de decisiones de la importancia de establecer este tipo de programas en el país, ya que aún existe una alta mortalidad relacionada con la muerte cardíaca súbita.

Heart defibrillation: relationship between pacing threshold and defibrillation probability.

BACKGROUND: Considering the clinical importance of the ventricular fibrillation and that the most used therapy to reverse it has a critical side effect on the cardiac tissue, it is desirable to optimize defibrillation parameters to increase its efficiency. In this study, we investigated the influence of stimuli duration on the relationship between pacing threshold and defibrillation probability. RESULTS: We found out that 0.5-ms-long pulses had a lower ratio of defibrillation probability to the pacing threshold, although the higher the pulse duration the lower is the electric field intensity required to defibrillate the hearts. CONCLUSION: The appropriate choice of defibrillatory shock parameters is able to increase the efficiency of the defibrillation improving the survival chances after the occurrence of a severe arrhythmia. The relationship between pulse duration and the probability of reversal of fibrillation shows that this parameter cannot be underestimated in defibrillator design since different pulse durations have different levels of safety.

Study of morphological properties and rheological parameters of cellulose nanofibrils of cocoa shell (Theobroma cacao L.).

Cocoa shell was evaluated as a precursor for cellulose nanofibrils (NFCs) using mechanical defibrillation. Its morphology was analysed using optical microscopy and scanning electron microscopy with field emission. Rheological and mechanical behaviour were evaluated through flow curves with a strain rate ranging from 0 to 300 s-1 at 25 °C and by means of oscillatory frequency sweeps (0.01 Hz-10 Hz) and shear stress (3 Pa). The thermal-mechanical behaviour was determined by a temperature sweep with a heating rate of 3 °C min-1 and a temperature range of 25 °C-100 °C. Micrographs identified the presence of protoxilem with a mean diameter of 23.34 nm. The flow curve showed the characteristic behaviour of a pseudoplastic fluid. The storage module (G') and the loss modulus (G″) were dependent on the frequency applied, indicating that the material exhibits a weak gel characteristic. The viscoelastic characteristics were influenced by temperature. Therefore, cocoa shell is a new alternative in the production of nanocellulose.

New insight on the relationship between lethal electrical fields versus cardiomyocyte orientation

Abstract Introduction Cardiovascular diseases represent a major cause of death world-wide and one of their greatest complications is the development of cardiac arrhythmias, in which ventricular fibrillation (VF) stands out as the most severe one. The only therapy that reverses VF is defibrillation. However defibrillatory shock is capable of killing heart cells and it is known that the orientation of the cell major axis with respect to the electrical field (E) direction is a determining factor for cellular excitation and injury, which is leading to the development of new defibrillation protocols. The aim of this work is to fill the gap in information about cell lethality for intermediate cell orientation angles. Methods Ventricular myocytes were extracted from adult male Wistar rats and the cells were plated in a chamber for perfusion and stimulation with bipolar voltage pulses to determine the stimulation threshold (ET). Then, monopolar stimulus was applied and amplitude was increased until cell lethal injury. This protocol was performed on four experimental groups: cells oriented at 0°, 30°, 60° and 90°, with respect to E direction. Results 87 cells were analyzed and an increase in amplitude of E associated with 50% lethality (E50) was verified as the direction of E application and cell major axis orientation departed. Conclusion Taken the same probability of lethality, our data suggest a nonlinear increase of E amplitude from 0° to 90° similar to that of ET. These in-between data had not yet been shown and are important for service-based future defibrillation protocols.

Cardiomyocyte lethality by multidirectional stimuli.

Multidirectional defibrillation protocols have shown better efficiency than monodirectional; still, no testing was performed to assess cell lethality. We investigated lethality of multidirectional defibrillator-like shocks on isolated cardiomyocytes. Cells were isolated from adult male Wistar rats and plated into a perfusion chamber. Electrical field stimulation threshold (ET) was obtained, and cells were paced with suprathreshold bipolar electrical field (E) pulses. Either one monodirectional high-intensity electrical field (HEF) pulse aligned at 0° (group Mono0) or 60° (group Mono60) to cell major axis or a multidirectional sequence of three HEF pulses aligned at 0°, 60°, and 120° each was applied. If cell recovered from shock, pacing was resumed, and a higher amplitude HEF, proportional to ET, was applied. The sequence was repeated until cell death. Lethality curves were built by means of survival analysis from sub-lethal and lethal E. Non-linear fit was performed, and E values corresponding to 50% probability of lethality (E50) were compared. Multidirectional groups presented lethality curves similar to Mono0. Mono60 displayed the highest E50. The novel data endorse the idea of multidirectional stimuli being safer because their effects on lethality of individual cells were equal to a single monodirectional stimulus, while their defibrillatory threshold is lower. Graphical abstract Monodirectional and multidirectional lethality protocol comparison on isolated rat cardiomyocytes. The heart image is a derivative of "3D Heart in zBrush" ( https://vimeo.com/65568770 ) by Laloxl, used under CC BY 3.0 ( https://creativecommons.org/licenses/by/3.0/legalcode )/image extracted from original video.

Make it two: A case report of dual sequential external defibrillation.

ABSTRACTDual sequential external defibrillation (DSED) is the process of near simultaneous discharge of two defibrillators with differing pad placement to terminate refractory arrhythmias. Previously used in the electrophysiology suite, this technique has recently been used in the emergency department and prehospital setting for out-of-hospital cardiac arrest (OHCA). We present a case of successful DSED in the emergency department with neurologically intact survival to hospital discharge after refractory ventricular fibrillation (RVF) and review the putative mechanisms of action of this technique.

Survival After Ventricular Fibrillation Cardiac Arrest in the Sao Paulo Metropolitan Subway System: First Successful Targeted Automated External Defibrillator (AED) Program in Latin America.

BACKGROUND: Targeted automated external defibrillator (AED) programs have improved survival rates among patients who have an out-of-hospital cardiac arrest (OHCA) in US airports, as well as European and Japanese railways. The Sao Paulo (Brazil) Metro subway carries 4.5 million people per day. A targeted AED program was begun in the Sao Paulo Metro with the objective to improve survival from cardiac arrest. METHODS AND RESULTS: A prospective, longitudinal, observational study of all cardiac arrests in the Sao Paulo Metro was performed from September 2006 through November 2012. This study focused on cardiac arrest by ventricular arrhythmias, and the primary endpoint was survival to hospital discharge with minimal neurological impairment. A total of 62 patients had an initial cardiac rhythm of ventricular fibrillation. Because no data on cardiac arrest treatment or outcomes existed before beginning this project, the first 16 months of the implementation was used as the initial experience and compared with the subsequent 5 years of full operation. Return of spontaneous circulation was not different between the initial 16 months and the subsequent 5 years (6 of 8 [75%] vs. 39 of 54 [72%]; P=0.88). However, survival to discharge was significantly different once the full program was instituted (0 of 8 vs. 23 of 54 [43%]; P=0.001). CONCLUSIONS: Implementation of a targeted AED program in the Sao Paulo Metro subway system saved lives. A short interval between arrest and defibrillation was key for good long-term, neurologically intact survival. These results support strategic expansion of targeted AED programs in other large Latin American cities.

Resucitación utilizando desfibrilador externo automático en el Uruguay / Resuscitation with automated external defibrillator (AED) in Uruguay

Objetivo: comunicar las características de presentación y la sobrevida de un grupo de pacientes que sufrieron una muerte súbita (MS) y fueron asistidos con resucitación cardíaca básica (RCB) y desfibrilador externo automático (DEA) antes de la llegada de una emergencia médica móvil (EMM). Método: se realizó un estudio descriptivo-analítico de todos los paros cardíacos (PC) asistidos con DEA entre el 1° de enero de 2005 y el 1° de setiembre de 2013 en Uruguay. Se evaluaron las características de los pacientes, de los PC y la evolución posterior. Resultados: los DEA instalados en lugares públicos y con personal entrenado fueron utilizados en 37 eventos. En un caso de fibrilación ventricular (FV), el DEA no indicó descarga. En 23 pacientes (62,2%) se logró RCE y 14 (43%) sobrevivieron y retornaron a una vida activa. De los 27 PC en FV, 19 (70%) lograron retorno a la circulación espontánea (RCE) y 14 (52%) sobrevivió y se reintegró a sus tareas habituales. Los factores asociados a supervivencia al egreso hospitalario y reintegro a sus actividades fueron: la edad (57±9,9 en sobrevivientes versus 67±18,5 en fallecidos, p=0,041) y haber recibido RCB antes de 2 minutos versus > de 2 minutos (p=0,025). Conclusiones: los DEA instalados en lugares públicos y con personal entrenado fueron utilizados efectivamente en 36 eventos. Los resultados observados fueron similares a los reportados en series internacionales. La menor edad y la RCB antes de 2 minutos se asociaron a mejores resultados.

Purpose: to communicate the presentation features and survival of sudden death victims that were assisted with cardiopulmonary resuscitation (CPR) and automatic external defibrillator (AED) before the arrival of prehospital emergency medical system (PHEMS) in Uruguay. Method: case series study of all out of hospital cardiac arrest (OHCA) victims assisted with an AED from January 1, 2005 to September 1, 2013 in Uruguay. Patient’s features, cardiac arrest rhythm and evolution were evaluated. Results: 37 events in places with public access AED and trained people were reported. An AED decided ¨non shockable¨ in one ventricular fibrillation (VF) episode. Return of spontaneous circulation (ROSC) rate was 62,2% and 43% of the victims survived and returned to normal life. There were 27 VF cases. ROSC rate and survival for VF cases was 70% and 52% respectively. Every survivor of VF cases returned to normal life. Survival to Hospital discharge and return to normal life were associated with: VF (p=0,085), age (57 vs. 67 years, p=0,041) and bystander CPR before 2 minutes (p=0,025). Conclusion: public access AED were were effectively utilized in 36 cases. The results are similar to international reports and superior to those observed in the OHCA series assisted by PHEMS in our country. Lower age and bystander CPR before 2 minutes were associated with better outcomes.

Meta-analysis of continuous oral anticoagulants versus heparin bridging in patients undergoing CIED surgery: reappraisal after the BRUISE study.

BACKGROUND: Management of patients treated with oral anticoagulation (OAC) requiring a cardiovascular implantable electronic device (CIED) surgery is a challenge that requires balancing the risk of bleeding complications with the risk of thromboembolic events. Recently the approach of performing these procedures while the patient remains with a therapeutic international normalized ratio has gained interest due to several publications showing its relative safety. OBJECTIVES: To evaluate the safety and effectiveness of continuous use of OAC compared with heparin bridging in the perioperative setting of CIED surgery using a meta-analysis. METHODS: A systematic review of PubMed/MEDLINE, Ovid, and Elsevier databases was performed. Eligible randomized controlled trials and cohort studies were included. The outcomes studied were risk of clinically significant bleeding and of thromboembolic events. Our analysis was restricted to OAC with vitamin K antagonists. RESULTS: Of 560 manuscripts initially considered relevant, seven were included in the meta-analysis, totaling 2,191 patients. Data are reported as odds ratios (ORs) with confidence interval (CI) of 95%. Maintenance of OAC was associated with a significantly lower risk of postoperative bleeding compared with heparin bridge (OR = 0.25, 95% CI 0.17-0.36, P < 0.00001). There was no difference noted in the risk of thromboembolic events between the two strategies (OR = 1.86, 95% CI 0.29-12.17, P = 0.57). CONCLUSIONS: Uninterrupted use of OAC in the perioperative of CIED surgery was associated with a reduced risk of bleeding. This strategy should be considered the preferred one in patients at moderate-to-high risk of thromboembolic events.

Long-term follow-up of patients with chronic chagas disease and implantable cardioverter-defibrillator.

BACKGROUND/OBJECTIVES: Chronic Chagas heart disease (ChHD) is associated with ventricular tachyarrhythmias and an increased risk of sudden cardiac death. Little is known about the effectiveness of implantable cardioverter-defibrillator (ICD) therapy in this population. The objective of this study was to evaluate the efficacy of ICD in patients with ChHD and to identify predictors of mortality and appropriate ICD shocks. METHODS: The cohort study included 65 patients with ChHD and ICD for primary and secondary prevention of sudden death. The Cox model was applied to evaluate the predictors of mortality, and survival was assessed by Kaplan-Meier analysis. RESULTS: The median age was 56 ± 11.9 years. The median follow-up was 40 ± 26.8 months. Among the patients 23 (36.5%) had appropriate shocks. A total of 13 (20%) patients died (6.1% of annual mortality rate), and there was no sudden death. In univariate Cox model, functional class IV (hazard ratio [HR] = 1.99; 95% confidence interval [CI], 1.05-3.76; P = 0.034), primary prevention (HR = 0.29; 95% CI, 0.09-0.99; P = 0.048), lower education (HR = 2.51; 95% CI, 1.05-5.99; P = 0.038), and ejection fraction <30% (HR = 2.80; 95% CI, 1.09-7.18; P = 0.032) were predictors of worse prognosis (death). In the multivariate Cox model, an ejection fraction <30% and the low education remained predictors of poor prognosis. Predictors of appropriate shocks were not found. CONCLUSIONS: The ICD was effective for the prevention of sudden cardiac death in patients with chronic ChHD. An ejection fraction <30% and low education were predictors of poor prognosis.

Resultados iniciales de la implementación de programas de acceso público a la desfibrilación en Uruguay

Objetivo: comunicar las características de presentación y la sobrevida de un grupo de pacientes que sufrieron una MS y fueron asistidos con RCB y DEA antes de la llegada de una EMM. Material y método: se realizó un estudio descriptivo-analítico, retrospectivo, de todos los PCEH asistidos con DEA entre el 1° de enero de 2005 y el 1° de setiembre de 2011 en todo el país. Se evaluaron las características de los pacientes, de los PC y la evolución posterior. Resultados: los DEA instalados en lugares públicos y con personal entrenado fueron utilizados efectivamente en 24 eventos. El 62,5% logró RCE y el 45,8% sobrevivió y retornó a la vida activa. De los 16 PC en FV, 75% logró RCE y 56,3% sobrevivió y se reintegró a sus tareas habituales. Las personas que participaron de la resucitación y habían recibido entrenamiento previo en RCB y uso de DEA actuaron con celeridad y eficacia. Conclusiones: los DEA instalados en lugares públicos funcionaron adecuadamente. Los resucitadores no médicos probaron su idoneidad en la realización de las maniobras de resucitación El índice de RCE y de sobrevida al ingreso y al alta hospitalaria de nuestros pacientes fue adecuado y comparable a la casuística internacional.

Objective: to communicate the characteristics of presentation and survival in a group of patients who suffered Sudden Death and were assisted with Basic Cardiac Resuscitation and AED before the arrival of a Mobile Medical Emergency. Materials and methods: This was a descriptive-analytic study, retrospective, of all AED-assisted OHCA between January 1st, 2005 and September 1, 2011 throughout the country. Evaluated the characteristics of the patients and the cardiac arrest, and subsequent developments. Results: AEDs installed in public places with trained personnel were used effectively in 24 events. 62.5% achieved ROSC and 45.8% survived and returned to active life. Of the 16 Ventricular Fibrilation Cardiac Arrest, 75% achieved ROSC and 56.3% survived and returned to normal activities. People who participated in the resuscitation and had received previous training in cardiac resuscitation and AED use acted quickly and effectively. Conclusions: AEDs installed in public places worked properly. Nonmedical resuscitators probed their suitability in performing resuscitation. The rate of return of spontaneous circulation and survival to admission and discharge to the hospital of our patients was adequate and comparable to international reports.

The influence of cell dimensions on the vulnerability of ventricular myocytes to lethal injury by high-intensity electrical fields / Influência das dimensões celulares sobre a vulnerabilidade de miócitos ventriculares ao efeito letal de campos elétricos de alta intensidade

Application of high intensity electric fields (HIEF) to the myocardium is commonly used for cardiac defibrillation/cardioversion. Although effective at reversing life-threatening arrhythmias, HIEF may cause myocyte damage due to membrane electropermeabilization. In this study, the influence of cell length and width on HIEF-induced lethal injury was analyzed in isolated rat cardiomyocytes in parallel alignment with the field. The field-induced maximum variation of membrane potential (ΔVmax) was estimated with the Klee-Plonsey model. The studied myocyte population was arranged in two group pairs for comparison: the longest vs. the shortest cells, and the widest vs. narrowest cells. Threshold field intensity was significantly lower in the longest vs. shortest myocytes, whereas cell width influence was not significant. The threshold ΔVmax was comparable in all groups. Likewise, a significant leftward shift of the lethality curve (i.e., relationship of the probability of lethality vs. field intensity) of the longest cells was observed, evidencing greater sensitivity to HIEF-induced damage. However, the lethality curve as a function of ΔVmax was similar in all groups, confirming a prediction of the Klee-Plonsey model. The similar results for excitation and injury at threshold and HIEF stimulation, respectively, indicate that: a) the effect of cell length on the sensitivity to the field would be attributable to differences in field-induced membrane polarization that lead to excitation or lethal electroporation; b) the Klee-Plonsey model seems to be reliable for analysis of cell interaction with HIEF; c) it is possible that increased cell length in hypertrophied hearts enhances myocyte fragility upon defibrillation/cardioversion.

Campos elétricos de alta intensidade (HIEF) são aplicados ao miocárdio durante desfibrilação e cardioversão. Embora eficazes na reversão de arritmias potencialmente letais, HIEF podem lesar cardiomiócitos por eletropermeabilização da membrana. Neste estudo, a influência das dimensões celulares sobre o efeito letal de HIEF foi estudada em cardiomiócitos isolados de rato alinhados paralelamente ao campo. A máxima variação do potencial de membrana induzida pelo campo (ΔVmax) foi calculada com o modelo de Klee-Plonsey. As células estudadas foram distribuídas em dois pares de grupos de acordo com seu comprimento e largura. A intensidade limiar do campo não dependeu da largura celular, mas sim do comprimento (menor nas células mais longas, p < 0.001), enquanto ΔVmax no limiar foi comparável entre os grupos. Nas células mais longas, observou-se desvio à esquerda (p < 0.01) da curva que descreve a relação entre probabilidade de letalidade e a intensidade do campo, evidenciando maior sensibilidade à ação deletéria de HIEF. Porém, a curva de letalidade em função de ΔVmax foi semelhante em todos os grupos, o que confirma a predição pelo modelo de Klee-Plonsey. A similaridade de resultados com estimulação limiar e com HIEF indica que: a) o efeito do comprimento celular sobre a sensibilidade ao campo poderia ser atribuído a diferenças no grau de polarização da membrana durante a aplicação do estímulo; b) o modelo de Klee-Plonsey parece ser confiável para a análise da interação espacial da célula com HIEF; c) é possível que o maior comprimento celular em miócitos hipertrofiados os torne mais susceptíveis a lesão durante desfibrilação/cardioversão.