Coma Prevalence in Critical Care Units in Chile: Results of a Cross-Sectional Survey on World Coma Day.

BACKGROUND: The purpose of this study was to assess the prevalence of coma among patients in critical care units in Chile. We also aimed to provide insight into the demographic characteristics, etiologies, and complications associated with coma. METHODS: A single day cross-sectional study was conducted through a national survey of public and private hospitals with critical and intensive cardiac care units across Chile. Data were collected using an online questionnaire that contained questions regarding critically ill patients' information, demographic characteristics, etiology and duration of coma, medical complications, and support requirements. RESULTS: A total of 84% of all health facilities answered, accounting for a total of 2,708 patients. The overall coma prevalence was 2.9%. The median age of the comatose patients was 61 years (interquartile range 50-72) and 66.2% were male. The median coma duration was five days (interquartile range 2-9). Cerebral hemorrhage was the most common etiology, followed by severe hypoxic-ischemic encephalopathy, acute ischemic stroke, and traumatic brain injury. A total of 48.1% of coma patients experienced acute and ongoing treatment complications, with pneumonia being the most common complication, and 97.4% required support during comatose management. CONCLUSIONS: This study provides an overview of the prevalence of coma in Chilean critical and cardiac care units. Coma is a common condition. Comatose patients frequently experience medical complications during their hospitalization.

Development of a Smartwatch with Gas and Environmental Sensors for Air Quality Monitoring.

In recent years, there has been a growing interest in developing portable and personal devices for measuring air quality and surrounding pollutants, partly due to the need for ventilation in the aftermath of COVID-19 situation. Moreover, the monitoring of hazardous chemical agents is a focus for ensuring compliance with safety standards and is an indispensable component in safeguarding human welfare. Air quality measurement is conducted by public institutions with high precision but costly equipment, which requires constant calibration and maintenance by highly qualified personnel for its proper operation. Such devices, used as reference stations, have a low spatial resolution since, due to their high cost, they are usually located in a few fixed places in the city or region to be studied. However, they also have a low temporal resolution, providing few samples per hour. To overcome these drawbacks and to provide people with personalized and up-to-date air quality information, a personal device (smartwatch) based on MEMS gas sensors has been developed. The methodology followed to validate the performance of the prototype was as follows: firstly, the detection capability was tested by measuring carbon dioxide and methane at different concentrations, resulting in low detection limits; secondly, several experiments were performed to test the discrimination capability against gases such as toluene, xylene, and ethylbenzene. principal component analysis of the data showed good separation and discrimination between the gases measured.

"THE MANTLE" bundle for minimizing cerebral hypoxia in severe traumatic brain injury.

To ensure neuronal survival after severe traumatic brain injury, oxygen supply is essential. Cerebral tissue oxygenation represents the balance between oxygen supply and consumption, largely reflecting the adequacy of cerebral perfusion. Multiple physiological parameters determine the oxygen delivered to the brain, including blood pressure, hemoglobin level, systemic oxygenation, microcirculation and many factors are involved in the delivery of oxygen to its final recipient, through the respiratory chain. Brain tissue hypoxia occurs when the supply of oxygen is not adequate or when for some reasons it cannot be used at the cellular level. The causes of hypoxia are variable and can be analyzed pathophysiologically following "the oxygen route." The current trend is precision medicine, individualized and therapeutically directed to the pathophysiology of specific brain damage; however, this requires the availability of multimodal monitoring. For this purpose, we developed the acronym "THE MANTLE," a bundle of therapeutical interventions, which covers and protects the brain, optimizing the components of the oxygen transport system from ambient air to the mitochondria.

Portable Electronic Nose Based on Digital and Analog Chemical Sensors for 2,4,6-Trichloroanisole Discrimination.

2,4,6-trichloroanisole (TCA) is mainly responsible for cork taint in wine, which causes significant economic losses; therefore, the wine and cork industries demand an immediate, economic, noninvasive and on-the-spot solution. In this work, we present a novel prototype of an electronic nose (e-nose) using an array of digital and analog metal-oxide gas sensors with a total of 31 signals, capable of detecting TCA, and classifying cork samples with low TCA concentrations (≤15.1 ng/L). The results show that the device responds to low concentrations of TCA in laboratory conditions. It also differentiates among the inner and outer layers of cork bark (81.5% success) and distinguishes among six different samples of granulated cork (83.3% success). Finally, the device can predict the concentration of a new sample within a ±10% error margin.

A Novel Bike-Mounted Sensing Device with Cloud Connectivity for Dynamic Air-Quality Monitoring by Urban Cyclists.

We present a device based on low-cost electrochemical and optical sensors, designed to be attached to bicycle handlebars, with the aim of monitoring the air quality in urban environments. The system has three electrochemical sensors for measuring NO2 and O3 and an optical particle-matter (PM) sensor for PM2.5 and PM10 concentrations. The electronic instrumentation was home-developed for this application. To ensure a constant air flow, the input fan of the particle sensor is used as an air supply pump to the rest of the sensors. Eight identical devices were built; two were collocated in parallel with a reference urban-air-quality-monitoring station and calibrated using a neural network (R2 > 0.83). Several bicycle routes were carried out throughout the city of Badajoz (Spain) to allow the device to be tested in real field conditions. An air-quality index was calculated to facilitate the user's understanding. The results show that this index provides data on the spatiotemporal variability of pollutants between the central and peripheral areas, including changes between weekdays and weekends and between different times of the day, thus providing valuable information for citizens through a dedicated cloud-based data platform.

Low-Cost Air Quality Measurement System Based on Electrochemical and PM Sensors with Cloud Connection.

This paper presents a portable device for outdoor air quality measurement that provides concentration values for the main pollutants: NO2, NO, CO, O3, PM2.5 and PM10, and other values such as temperature, humidity, location, and date. The device is based on the use of commercial electrochemical gas and optical particle matter sensors with a careful design of the electronics for reducing the electrical noise and increasing the accuracy of the measurements. The result is a low-cost system with IoT technology that connects to the Internet through a GSM module and sends all real-time data to a cloud platform with storage and computational potential. Two identical devices were fabricated and installed on a mobile reference measurement unit and deployed in Badajoz, Spain. The results of a two-month field campaign are presented and published. Data obtained from these measurements were calibrated using linear regression and neural network techniques. Good performance has been achieved for both gaseous pollutants (with a Pearson correlation coefficient of up to 0.97) and PM sensors.

Electronic Nose with Digital Gas Sensors Connected via Bluetooth to a Smartphone for Air Quality Measurements.

This paper introduces a miniaturized personal electronic nose (39 mm × 33 mm), which is managed through an app developed on a smartphone. The electronic nose (e-nose) incorporates four new generation digital gas sensors. These MOx-type sensors incorporate a microcontroller in the same package, being also smaller than the previous generation. This makes it easier to integrate them into the electronics and improves their performance. In this research, the application of the device is focused on the detection of atmospheric pollutants in order to complement the information provided by the reference stations. To validate the system, it has been tested with different concentrations of NOx including some tests specifically developed to study the behavior of the device in different humidity conditions. Finally, a mobile application has been developed to provide classification services. In this regard, a neural network has been developed, trained, and integrated into a smartphone to process the information retrieved from e-nose devices.

Wireless Sensor Network Combined with Cloud Computing for Air Quality Monitoring.

Low-cost air pollution wireless sensors are emerging in densely distributed networks that provide more spatial resolution than typical traditional systems for monitoring ambient air quality. This paper presents an air quality measurement system that is composed of a distributed sensor network connected to a cloud system forming a wireless sensor network (WSN). Sensor nodes are based on low-power ZigBee motes, and transmit field measurement data to the cloud through a gateway. An optimized cloud computing system has been implemented to store, monitor, process, and visualize the data received from the sensor network. Data processing and analysis is performed in the cloud by applying artificial intelligence techniques to optimize the detection of compounds and contaminants. This proposed system is a low-cost, low-size, and low-power consumption method that can greatly enhance the efficiency of air quality measurements, since a great number of nodes could be deployed and provide relevant information for air quality distribution in different areas. Finally, a laboratory case study demonstrates the applicability of the proposed system for the detection of some common volatile organic compounds, including: benzene, toluene, ethylbenzene, and xylene. Principal component analysis, a multilayer perceptron with backpropagation learning algorithm, and support vector machine have been applied for data processing. The results obtained suggest good performance in discriminating and quantifying the concentration of the volatile organic compounds.

Patient-Specific Factors Drive Intensive Care Unit and Total Hospital Length of Stay in Operative Patients with Brain Tumor.

BACKGROUND: Hospital length of stay (LOS) is an important cost driver in neurosurgery. Broader surgical literature has shown that patient-related factors, including comorbidities, and procedure-related factors, such surgeon experience, may be associated with LOS. Because value optimization strategies may be targeted toward either domain, this study investigated the contributions of patient-related and procedure-related factors in predicting prolonged intensive care unit LOS (iLOS) and total hospital LOS (tLOS). METHODS: Data for adult patients undergoing brain tumor surgery (2017-2019) were collected. Bivariate analyses for iLOS and tLOS were performed using the Mann-Whitney U test and Fisher exact test. Variables associated with either outcome with P < 0.10 were included in patient-only, procedure-only, and patient+procedure factor multivariate linear regression models. Model discrimination was quantified using C-statistics. RESULTS: Our 654 patients had a mean age of 57.54 years (standard deviation, ± 14.34 years). For iLOS, the patient-only model significantly outperformed the procedure-only model (P < 0.0001) and performed similarly to the patient+procedure model (P = 0.50). Other than tumor diagnosis, 5-Factor Modified Frailty Index score was the only factor associated with iLOS (P < 0.001) and tLOS (P < 0.001) on multivariate analysis. When predicting prolonged tLOS, the patient-only model significantly outperformed the procedure-only model (P < 0.0001), and performed similarly to patient+procedure models (P = 0.49). CONCLUSIONS: Patient-specific factors are the main drivers of prolonged iLOS and tLOS among patients with brain tumor. Frailty was significantly associated with both iLOS and tLOS on multivariate analysis. Efforts to improve care value should focus on strategies to optimize patient status, such as prehabilitation and enhanced recovery after surgery.

A membrane-biofilm system for sulfate conversion to elemental sulfur in mining-influenced waters.

A system of two membrane biofilm reactors (MBfRs) was tested for the conversion of sulfate (1.5 g/L) in mining-process water into elemental sulfur (S0) particles. Initially, a H2-based MBfR reduced sulfate to sulfide, and an O2-based MBfR then oxidized sulfide to S0. Later, the two MBfRs were coupled by a recirculation flow. Surface loading, reactor-coupling configuration, and substrate-gas pressure exerted important controls over performance of each MBfR and the coupled system. Continuously recirculating the liquid between the H2-based MBfR and the O2-based MBfR, compared to series operation, avoided the buildup of sulfide and gave overall greater sulfate removal (99% vs 62%) and production of S0 (61% vs 54%). The trade-off was that recirculation coupling demanded greater delivery of H2 and O2 (in air) due to the establishment of a sulfur cycle catalyzed by Sulfurospirillum spp., which had an average abundance of 46% in the H2-based MBfR fibers and 62% in the O2-based MBfR fibers at the end of the experiments. Sulfate-reducing bacteria (Desulfovibrio and Desulfomicrobium) and sulfur-oxidizing bacteria (Thiofaba, Thiomonas, Acidithiobacillus and Sulfuricurvum) averaged only 22% and 11% in the H2-based MBfR and O2-based MBfR fibers, respectively. Evidence suggests that the undesired Sulfurospirillum species, which reduce S0 to sulfide, can be suppressed by increasing sulfate-surface loading and H2 pressure.

Influence of operating conditions on sulfate reduction from real mining process water by membrane biofilm reactors.

Two H2-based membrane biofilm reactor (H2-MBfR) systems, differing in membrane type, were tested for sulfate reduction from a real mining-process water having low alkalinity and high concentrations of dissolved sulfate and calcium. Maximum sulfate reductions were 99%, with an optimum pH range between 8 and 8.5, which minimized any toxic effect of unionized hydrogen sulfide (H2S) on sulfate-reducing bacteria (SRB) and calcite scaling on the fibers and in the biofilm. Although several strategies for control of pH and gas back-diffusion were applied, it was not possible to sustain a high degree of sulfate reduction over the long-term. The most likely cause was precipitation of calcite inside the biofilm and on the surface of fibers, which was shown by scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) analysis. Another possible cause was a decline in pH, leading to inhibition by H2S. A H2/CO2 mixture in the gas supply was able to temporarily recover the effectiveness of the reactors and stabilize the pH. Biomolecular analysis showed that the biofilm was comprised of 15-20% SRB, but a great variety of autotrophic and heterotrophic genera, including sulfur-oxidizing bacteria, were present. Results also suggest that the MBfR system can be optimized by improving H2 mass transfer using fibers of higher gas permeability and by feeding a H2/CO2 mixture that is automatically adjusted for pH control.

Triangular Test of Amanita Mushrooms by Using Electronic Nose and Sensory Panel.

This work aims to advance understanding of the differentiation of mushroom species through electronic devices that use sensors of various technologies and techniques for pattern recognition, comparing mainly volatile substances that emanate from them. In this first phase, the capacity of human olfaction to differentiate between the smell released by different wild mushrooms of the genus Amanita was analyzed by means of a triangular sensory test, comparing later the data to those obtained for the same samples with an electronic nose in a similar test. The results, still very preliminary, encourage imagining the wide application that these techniques will have and the feedback that this application can suppose for the training of the sense of human olfaction.

Bluetooth gas sensing module combined with smartphones for air quality monitoring.

This study addresses the development of a miniaturized (60 × 60 mm) Wireless Sensing Module (WSM) for environmental application and air quality detection. The proposed prototype has six sensors: one for humidity, one for ambient temperature (SHT21 from Sensirion), and four for gas detection (MiCS-4514, MiCS-5526 and MiCS-5914 from SGX Sensortech). The core of the system is based on a high performance 8-bit microcontroller, model PIC18F46K80, from Microchip. The obtained data values were transmitted to the Smartphone through a Bluetooth communication module and a home-developed Android app. The discrimination capability of the module is tested with 10 volatile organic compounds (acetone, acetic acid, benzene, ethanol, ethyl acetate, ethylbenzene, formaldehyde, toluene, xylene, and dimethylacetamide) and the effect of humidity and drift of the sensors is also studied. Results show that 88.33% and 92.22% success rates in classification stage are obtained using Multilayer Perceptron with BackPropagation Learning algorithm and Radial-Basis based Neural Networks, respectively.

MRI-based in vivo assessment of early cerebral infarction in a mouse filament perforation model of subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Experimental subarachnoid hemorrhage (SAH) by endovascular filament perforation method is used widely in mice, but it sometimes present acute cerebral infarctions with varied magnitude and anatomical location. This study aimed to determine the prevalence and location of the acute ischemic injury in this experimental model. METHODS: Male C57BL/6 mice were subjected to SAH by endovascular perforation. Distribution of SAH was defined by T2*-weighted images within 1h after SAH. Prevalence and location of acute infarction were assessed by diffusion-weighted MR images on day 1 after the induction. RESULTS: Among 72 mice successfully acquired post-SAH MR images, 29 (40%) developed acute infarction. Location of the infarcts was classified into either single infarct (ipsilateral cortex, n=12; caudate putamen, n=3; hippocampus, n=1) or multiple lesions (cortex and caudate putamen, n=6; cortex and hippocampus, n=2; cortex, hippocampus and thalamus/hypothalamus, n=3; bilateral cortex, n=2). The mortality rate within 24h was significantly higher in mice with multiple infarcts than those with single lesion (30% versus 0%; P=0.03). Distribution of the ischemic lesion positively correlated with MRI-evidenced SAH grading (r2=0.31, P=0.0002). CONCLUSION: Experimental SAH immediately after the vessel perforation can induce acute cerebral infarction in varying vascular territories, resulting in increased mortality. The present model may in part, help researchers to interpret the mechanism of clinically-evidenced early multiple combined infarction.

Factores influyentes en el desarrollo de competencias en Ortopedia y Traumatología durante el internado médico / Influential Factors in The Development of Competencies in Orthopedics and Traumatology During the Medical Internship

RESUMEN Introducción: Actualmente la salud es concebida como un derecho fundamental y para garantizarlo se debe propender por una adecuada formación de los profesionales de la salud. El internado rotatorio es la última etapa y la más importante del pregrado en Medicina. Objetivo: Explorar los factores desde la perspectiva de estudiantes y docentes, que influyen en el desarrollo de competencias en la rotación de Ortopedia y Traumatología durante el internado médico. Métodos: Estudio cualitativo con enfoque en teoría fundamentada. Para la recolección de datos se realizó un cuestionario semiestructurado a una muestra aleatoria de 14 participantes, 7 estudiantes y 7 docentes, que cumplían los criterios de inclusión. El análisis se basó en la codificación y categorización de los datos que posteriormente fueron sometidos a un proceso de triangulación para lograr la teorización final. Resultados: Los factores que favorecen el desarrollo de competencias están relacionados con la motivación intrínseca del estudiante, la flexibilidad y disponibilidad de recursos académicos, las características del programa de la rotación y el ambiente de práctica. Se identificaron como factores limitantes aquellos asociados a una formación deficiente en ciencias básicas médicas, la priorización del componente asistencial sobre el académico, la disponibilidad limitada de espacios y recursos de aprendizaje y los métodos de enseñanza tradicionales. Conclusiones: Es de vital importancia la identificación de los factores que favorecen y limitan el desarrollo de las competencias de los estudiantes de medicina en su última etapa de formación en ortopedia.

ABSTRACT Introduction: Few areas of orthopedic surgery have had such important technical changes in recent decades as in corrective spinal surgery. Fundamental changes have come with the new spinal instrumentation systems, which have been substantially modified and improved to facilitate three-dimensional correction of the deformity and provide secure spinal fixation, correction and stability. Objective: To evaluate the results achieved with the spinal instrumentation systems used in the correction of thoracolumbar kyphosis due to ankylosing spondylitis. Methods: A descriptive, retrospective and longitudinal study was carried out on 16 patients with thoracolumbar kyphosis due to ankylosing spondylitis operated on with the pedicle subtraction osteotomy technique and instrumented with Luque-type pedicle and sublaminar systems, in the Orthopedics service at Hermanos Ameijeiras Surgical Clinical Hospital, from March 2001 to March 2021. Results: All the patients were male, white skin color and average age of 39 years. More than 80% correction was achieved in the sagittal profile and an average of 34.3° per osteotomy, without major neurological complications. Good functional results were obtained, with high degree of patient satisfaction and improvement in their quality of life. Conclusions: The use of both spinal instrumentation systems is effective in maintaining the correction of thoracolumbar kyphosis due to ankylosing spondylitis.

On-line classification of pollutants in water using wireless portable electronic noses.

A portable electronic nose with database connection for on-line classification of pollutants in water is presented in this paper. It is a hand-held, lightweight and powered instrument with wireless communications capable of standalone operation. A network of similar devices can be configured for distributed measurements. It uses four resistive microsensors and headspace as sampling method for extracting the volatile compounds from glass vials. The measurement and control program has been developed in LabVIEW using the database connection toolkit to send the sensors data to a server for training and classification with Artificial Neural Networks (ANNs). The use of a server instead of the microprocessor of the e-nose increases the capacity of memory and the computing power of the classifier and allows external users to perform data classification. To address this challenge, this paper also proposes a web-based framework (based on RESTFul web services, Asynchronous JavaScript and XML and JavaScript Object Notation) that allows remote users to train ANNs and request classification values regardless user's location and the type of device used. Results show that the proposed prototype can discriminate the samples measured (Blank water, acetone, toluene, ammonia, formaldehyde, hydrogen peroxide, ethanol, benzene, dichloromethane, acetic acid, xylene and dimethylacetamide) with a 94% classification success rate.

Placa superior vs. placa antero-inferior en fracturas del tercio medio de la clavícula. Estudio de Cohorte longitudinal / Superior vs. Anteroinferior plating for midshaft clavicle fractures. A Cohort study

Introducción Las fracturas de clavícula son muy comunes, representan el 2.6% de todas las fracturas en la población adulta y el 35% de todas las lesiones del hombro. El objetivo de este estudio es determinar cuál es la mejor técnica quirúrgica entre los métodos tipo placa superior versus placa antero-inferior para el tratamiento de fracturas del tercio medio de clavícula. Materiales y métodos Se realizó un estudio de tipo cohorte longitudinal bajo criterios de inclusión, con seguimiento de 9 meses. Se midieron distintos desenlaces de la técnica quirúrgica y fueron utilizados los cuestionarios Dash y Constant Score para evaluar el grado de satisfacción y el resultado funcional, respectivamente. Este estudio cuenta con la aprobación del comité de ética institucional. Resultados Se seleccionaron 96 pacientes (44 sometidos a placa antero-inferior y 52 a placa superior). Los desenlaces medidos se comportan como factor protector para el método de placa antero-inferior: sangrado intraoperatorio (RR 0.60), tiempo quirúrgico (RR 0.52), de consolidación (RR 0.55), irritación del material (RR 0.12) y retiro del material (RR 0.25). Las diferencias respecto a resultados funcionales y grado de satisfacción también fueron estadísticamente significativas. Discusión En concordancia con la literatura, el método de placa antero-inferior demostró ser más seguro y recomendado que el de placa superior, pues mejora el tiempo de unión, reduce la tasa de retardo de la consolidación, el volumen de pérdida de sanguínea intra-operatoria y el tiempo quirúrgico, con mejor resultado funcional y grado de satisfacción en los pacientes.

Background Clavicle fractures are frequent injuries of the shoulder, with an overall incidence of 2.6% of all fractures among the adult population and 35% of all shoulder injuries. This study aims to determine whether dorsal plating or anterior/inferior plating is a better surgical technique for treating middle-third clavicle fractures. Methods A cohort study using inclusion criteria and involving a nine-month follow-up period was carried out. Different surgical technique outcomes were measured; Dash and Constant Score questionnaires, respectively, were used to assess the degree of satisfaction and functional outcome of patients. This study has the approval of the hospital's Ethics Committee. Results 96 patients were selected; 44 underwent anterior-inferior plating and 52 superior plating. The following measured variables are revealed as protective factors for anterior-inferior plating: operative blood loss volume (RR 0.60), operative time (RR 0.52), union rate (RR 0.55), irritation due to material (RR 0.12), and request for material extraction (RR 0.25). Differences regarding functional outcomes and patient satisfaction degrees were also statistically significant. Discussion According to literature, anterior-inferior proved to be safer than dorsal plating method and thus advisable, due to it reduces union time, retarded union rates, operative blood loss volume, and operative time; which results in better functional outcomes and greater patient satisfaction.

Update in the management of acute ischemic stroke.

Acute ischemic stroke is the fourth leading cause of death and the leading cause of disability in the United States. Stroke is a medical emergency. The development of stroke systems of care has changed the way practitioners view and treat this devastating disease. Ample evidence has shown that patients presenting early and receiving intravenous thrombolytic therapy have the best chance for significant improvement in functional outcome, particularly if they are transported to specialized stroke centers. Early detection and management of medical and neurologic complications is key at preventing further brain damage in patients with acute ischemic stroke.