Examinando por Materia "Ventilación mecánica"

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  • Miniatura
    PublicaciónAcceso abierto
    Mechanical ventilatory parameters based on a mathematical model for diagnosis/treatment of older adults with ARDS
    (Universidad del Valle, 2025) Ruiz Hidalgo, Iván Dario; Jaramillo Pizarro, Guillermo Andrés; garcia melo, jose isidro; CIENCIA, EDUCACIÓN Y DIVERSIDAD
    This study presents a novel mathematical model to estimate mechanical ventilatory parameters in older adults diagnosed with Acute Respiratory Distress Syndrome (ARDS). The proposed model, called the Recruitment and Distention Elastance Analysis + Slice model (RDEA + Slice), builds on the traditional Single Compartment Model (SCM) by incorporating new strategies for improved physiological representation. Validation with real patient data showed that RDEA + Slice offers enhanced numerical accuracy compared to conventional methods, especially during spontaneous breathing and patient-ventilator asynchronies. To further explore asynchrony detection, the pressure signal was interpreted as a combination of a synchronous baseline and "noise" from asynchronous activity. A frequency-domain filtering approach was used to isolate these components, leading to the formulation of two metrics: the Asynchrony Event Percentage (AE%) and the Asynchrony Index (AI%). These metrics were applied to three datasets, allowing for the identification of threshold-based criteria to distinguish between synchronous and asynchronous breathing patterns. Additionally, image processing techniques were validated and used to extract ventilatory data from video recordings of ventilator screens. This approach provides a practical solution for data acquisition in low-resource settings, a common challenge in emerging economies. The extracted data showed high fidelity and low Mean Squared Error when compared with sensor-derived measurements. The results suggest that the proposed model, detection indices, and image processing methodology could support clinical decision-making by providing insights into patient-specific respiratory mechanics.
  • Miniatura
    PublicaciónAcceso abierto
    Sensitivity and specificity of the Yang Tobin Index to predict extubation success in critical patients.
    (2012-01-03) Segura, Alejandro; Carvajal, Nathali; Chavarro, Paola Andrea; Wilches, Esther Cecilia; Carvajal, Argemiro
    Background: The Yang Tobin Index (Y/T) is a simple and objective measure to predict successful extubation. There are no Colombian studies supporting the use of Y/T as a predictor of successful ventilator weaning. Objective: To estimate the sensitivity and specificity of Y/T as predictor of weaning and to evaluate the association with clinical and socio-demographic characteristics in adult patients at the intensive care unit. Methods: Retrospective study. We analyzed a database of 332 records of patients under mechanical ventilation (MV) for more than 48 hours, from January 2006 to December 2007, with spontaneous breathing trial and measurement of Y/T before extubation. Results: The sensitivity of Y/T was 98.6%, specificity 9.6%, positive predictive value 85.4%, negative predictive value 55.5%. The cumulative incidence of successful extubation was 84%. The greater incidence of unsuccessful extubation was associated with COPD (46.2%). The MV time period showed a direct proportional relationship with failed extubation (p=0.186). Conclusions: The Y/T index is not a good predictor of success of extubation in the study population. No association was found between clinical and sociodemographic characteristics of the population, with respect to the sensitivity and specificity of the Y/T as a predictor of success. Introducción: El índice Yang Tobin (Y/T), es una medida sencilla y objetiva para predecir éxito en la extubación. A nivel nacional no existen estudios que sustenten el uso del índice como predictor de éxito de extubación. Objetivos: Estimar la sensibilidad y especificidad del índice de Y/T y evaluar la relación con las características clínicas y demográficas en pacientes adultos en una unidad de cuidado intensivo. Métodos: Estudio retrospectivo; se analizó la información consignada en 332 formatos de ventilación mecánica de los pacientes que recibieron soporte ventilatorio invasivo por más de 48 horas desde enero de 2006 a diciembre de 2007, con prueba de respiración espontánea y medición del índice Y/T antes de la extubación. Resultados: La sensibilidad del Y/T fue 98.6%, especificidad 9.6%, valor predictivo positivo 85.4%, valor predictivo negativo 55.5%. La incidencia acumulada de extubación exitosa fue 84%. La mayor incidencia acumulada de extubación no exitosa se asoció con EPOC (46.2%). El tiempo de ventilación mecánica mostró una relación directamente proporcional con extubación no exitosa (p=0.186). Conclusiones: El índice Y/T no es un buen predictor de éxito de la extubación en la población de estudio. No se encontró asociación entre características clínicas y sociodemográficas de la población, con respecto a la sensibilidad y especificidad del Y/T como predictor de éxito.