title: [Regional cerebral oxygen saturation as a marker of hemodynamic state following cardiac surgery].
abstract: BACKGROUND
  Regional cerebral oxygen saturation (rSO₂) is a measure of the general state of perfusion and oxygenation. We aim to analyze the relationship between this and various hemodynamic and respiratory parameters.
  
  
  METHODS
  Forty-three patients, operated on between October 2011 and July 2012, were included in this prospective observational descriptive study. The following parameters were measured: mean arterial pressure, both arterial and central venous oxygen saturation and partial pressures of oxygen and carbon dioxide, and lactate levels. From these parameters, the oxygenation index and the oxygen extraction ratio were calculated. These measurements were studied to evaluate whether rSO₂ correlated significantly with the other parameters.
  
  
  RESULTS
  The average age and weight of the patients were 27.3 months and 9.2 kg, respectively. The rSO₂ correlated positively with both central venous oxygen saturation (r=0.73, P<.01) and mean arterial pressure (r=0.59, P<.01), and negatively with the oxygen extraction ratio (r=-0.7, P<.01). No correlation was found with the respiratory parameters. Concordance analysis established an acceptable Kappa index (> 0.4) between the rSO₂ and central venous oxygen saturation, and between the rSO₂ and oxygen extraction ratio.
  
  
  CONCLUSIONS
  Regional cerebral oxygen saturation correlates well with hemodynamic parameters - mean arterial pressure, venous saturation, and the tissue oxygen extraction. However, it does not correlate with respiratory parameters.
authors.affiliation: Unidad de Gestión Clínica de Cuidados Críticos y Urgencias, Hospital Infantil Universitario Virgen del Rocío, Sevilla, España. Electronic address: garcier@gmail.com.
authors.forename: J A
authors.initials: JA
authors.lastname: García-Hernández
authors.forename: A
authors.initials: A
authors.lastname: Aldemira-Liz
authors.forename: A I
authors.initials: AI
authors.lastname: Martínez-López
authors.forename: A
authors.initials: A
authors.lastname: Cayuela
authors.forename: M T
authors.initials: MT
authors.lastname: Charlo-Molina
authors.forename: J
authors.initials: J
authors.lastname: Cano-Franco
authors.forename: M
authors.initials: M
authors.lastname: Loscertales-Abril
mesh_terms: D001921:Brain / Q000378:metabolism*; D006348:Cardiac Surgical Procedures; D002675:Child, Preschool; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010100:Oxygen / Q000378:metabolism*; D011446:Prospective Studies; D012119:Respiration
chemical_list: D010100:Oxygen
keywords: Cardiac surgery; Central venous oxygen saturation; Cerebral oximetry; Cirugía cardíaca; Cuidados perioperatorios; Espectroscopia cercana al infrarrojo; Near-infrared spectroscopy; Oximetría cerebral; Perioperative care; Saturación de oxígeno venosa central