Valor de la saturación regional cerebral de oxígeno como marcador del estado hemodinámico en el post-operatorio de cardiopatías congénitas en pacientes pediátricos
- Autores: A. Aldemira-Liz
- Directores de la Tesis: M. Loscertales Abril (dir. tes.), Juan Antonio García Hernández (codir. tes.), Ignacio Obando (tut. tes.)
- Lectura: En la Universidad de Sevilla ( España ) en 2014
- Idioma: español
- Tribunal Calificador de la Tesis: Francisco Murillo-Cabezas (presid.), Esther Ocete Hita (secret.), Aurelio Cayuela Domínguez (voc.), Elia Sánchez Valderrabanos (voc.), Ignacio Ibarra de la Rosa (voc.)
- Materias:
- Enlaces
- Tesis en acceso abierto en: TESEO
- Resumen
La saturación cerebral de oxígeno (rSO2c) es una medida del estado de perfusión y oxigenación de los tejidos, y su determinación se realiza mediante la espectrometría cercana al infrarrojo (NIRS). Esta técnica, basada en la relativa transparencia de los tejidos biológicos a la luz cercana al infrarrojo, proporciona una medición de la oxigenación tisular mediante la determinación cuantitativa del color de la hemoglobina en sangre. Así, el sistema NIRS valora de forma no invasiva, constante y a tiempo real la circulación tisular, reflejando tanto la entrega como el consumo de oxígeno en el tejido cerebral.
El objetivo ha sido analizar la relación entre la rSO2c y una serie de parámetros hemodinámicos, respiratorios e inflamatorios.
Entre Octubre de 2011 y Julio de 2012, se incluyeron 43 niños intervenidos de cirugía cardiovascular en un estudio prospectivo, observacional y descriptivo. Se midió la rSO2c y la tensión arterial media (TAM), y se realizaron gasometrías en sangre arterial y venosa. Se determinó la saturación arterial (SaO2), la saturación venosa (SvO2), la presión arterial de oxígeno (paO2) y el lactato; y se calculó la paO2/FiO2, el índice de oxigenación (IO) y la extracción de oxígeno (ETO2). También se analizaron los valores de glucemia y troponinas como marcadores inflamatorios y de daño miocárdico. Se analizaron estas mediciones para determinar si existían correlaciones significativas entre la rSO2c y los otros parámetros.
Las medias de edad y peso fueron de 27.3 meses y 9.2 Kg. Se encontró una correlación positiva de la rSO2c con la SvO2 (r = 0.73, p<0.01) y con la TAM (r = 0.59, p<0.01); y una correlación negativa con la ETO2 (r =- 0.7, p<0.01). El análisis de concordancia estableció un índice Kappa aceptable (> 0.5) entre la rSO2c y la SvO2, y entre la rSO2c y la ETO2 (p<0.001). En el análisis de las curvas COR entre la rSO2c y las variables TAM, SvO2 y ETO2, se obtuvieron áreas bajo la curva superiores a 0.7, correspondientes a test buenos o muy buenos (p<0.005). Se obtuvo una correlación negativa moderada con los niveles de glucemia y los de troponinas (r= -0.4_-0.5, p<0.01). La rSO2c no se correlacionó con las variables respiratorias analizadas.
La rSO2c puede predecir con bastante fiabilidad el valor de parámetros hemodinámicos indirectos como la ETO2 y la SvO2, además de detectar un cambio agudo tanto en estas variables como en la TAM. Por tanto, la rSO2c puede ser empleada como marcador indirecto del estado hemodinámico dentro de la monitorización postoperatoria de las cardiopatías congénitas, así como fuente de información suplementaria no invasiva sobre el equilibrio entre el aporte y el consumo de O2 a nivel cerebral, pero siempre junto a otras variables de valor ya contrastado en la monitorización hemodinámica.
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