Beyond volutrauma in ARDS: the critical role of lung tissue deformation

Ventilator-induced lung injury (VILI) consists of tissue damage and a biological response resulting from the application of inappropriate mechanical forces to the lung parenchyma. The current paradigm attributes VILI to overstretching due to very high-volume ventilation (volutrauma) and cyclic changes in aeration due to very low-volume ventilation (atelectrauma); however, this model cannot explain some research findings. In the present review, we discuss the relevance of cyclic deformation of lung tissue as the main determinant of VILI. Parenchymal stability resulting from the interplay of respiratory parameters such as tidal volume, positive end-expiratory pressure or respiratory rate can explain the results of different clinical trials and experimental studies that do not fit with the classic volutrauma/atelectrauma model. Focusing on tissue deformation could lead to new bedside monitoring and ventilatory strategies

Comparative study of four sigmoid models of pressure-volume curve in acute lung injury

BACKGROUND: The pressure-volume curve of the respiratory system is a tool to monitor and set mechanical ventilation in acute lung injury. Mathematical models of the static pressure-volume curve of the respiratory system have been proposed to overcome the inter- and intra-observer variability derived from eye-fitting. However, different models have not been compared. METHODS: The goodness-of-fit and the values of derived parameters (upper asymptote, maximum compliance and points of maximum curvature) in four sigmoid models were compared, using pressure-volume data from 30 mechanically ventilated patients during the early phase of acute lung injury. RESULTS: All models showed an excellent goodness-of-fit (R(2 )always above 0.92). There were significant differences between the models in the parameters derived from the inspiratory limb, but not in those derived from the expiratory limb of the curve. The within-case standard deviations of the pressures at the points of maximum curvature ranged from 2.33 to 6.08 cmH(2)O. CONCLUSION: There are substantial variabilities in relevant parameters obtained from the four different models of the static pressure-volume curve of the respiratory system

Programa de salud dirigido a familias de niños con Trastorno del espectro autista

Introducción: Los Trastornos del Espectro Autista son considerados como uno de los trastornos del desarrollo más comunes en el mundo. Se caracterizan por afectar a la comunicación e interacción social, al comportamiento y por presentar patrones repetitivos y restrictivos. En las últimas décadas se ha observado un aumento drástico de su prevalencia a nivel global. Un diagnóstico precoz en edades tempranas puede resultar de gran ayuda para favorecer el buen desarrollo de los niños con TEA y ayudar a sus familias, puesto que la crianza de un niño autista puede suponer una experiencia abrumadora. La implicación de los familiares en el plan de cuidados es esencial para lograr resultados óptimos a largo plazo en el desarrollo de distintas áreas como la comunicativa o la social.Objetivos: Diseñar un programa de educación para la salud para proporcionar ayuda a los familiares de niños con TEA, con el fin de orientar y mejorar su calidad de vida fomentando la implicación de los familiares en el plan de cuidados.Metodología: Se ha realizado una búsqueda bibliográfica a partir de bases de datos, guías de práctica clínica y páginas web. Se llevarán a cabo cuatro sesiones dirigidas a familiares de niños con TEA en el Centro de Salud de Actur Norte, las cuales serán evaluadas a través de una encuesta de evaluación pre y post sesiones y una encuesta de satisfacción.Conclusiones: El Programa de Salud es una herramienta efectiva no solo para facilitar información y orientación sino también para aportar recursos que ayuden a mejorar la calidad de vida de estas familias y conseguir mejorías importantes en estos niños.Palabras clave: "trastorno del Espectro Autista", "TEA," "familia, enfermería", "educación para la salud". <br /

A Simple Procedure to Measure the Tidal Volume Delivered by Mechanical Ventilators: A Tool for Bedside Verification and Quality Control

Mechanical ventilation is the most extensively employed life support intervention among patients with severe respiratory fail ure of different etiologies. In this context, consistent delivery of the most suitable tidal volume (VT) to the patientis criticalto achieving personalized mechanical ventilation. Indeed, in addition to its con tribution to minute volume for optimization of blood gas exchange,appropriate VT strategies are critical to avoid ventilator-induced lung injury in the general context of lung-protective ventilation and when specifically applying ultra-low tidal volume ventilation. Additionally, VT is required to compute respiratory system com pliance or ventilatory ratio, useful indices in the classification of patient phenotype and estimation of prognosis

MMP-8 Deficiency Increases TLR/RAGE Ligands S100A8 and S100A9 and Exacerbates Lung Inflammation during Endotoxemia

Matrix metalloproteinase-8, released mainly from neutrophils, is a critical regulator of the inflammatory response by its ability to cleave multiple mediators. Herein, we report the results of a model of endotoxemia after intraperitoneal LPS injection in mice lacking MMP-8 and their wildtype counterparts. Control, saline-treated animals showed no differences between genotypes. However, there was an increased lung inflammatory response, with a prominent neutrophilic infiltration in mutant animals after LPS treatment. Using a proteomic approach, we identify alarmins S100A8 and S100A9 as two of the main differences between genotypes. Mice lacking MMP-8 showed a significant increase in these two molecules in lung homogenates, but not in spleen and serum. Mice lacking MMP-8 also showed an increase in MIP-1α levels and a marked activation of the non-canonical NF-κB pathway, with no differences in CXC-chemokines such as MIP-2 or LIX. These results show that MMP-8 can modulate the levels of S100A8 and S100A9 and its absence promotes the lung inflammatory response during endotoxemia