Resumen de Medición del volumen corriente en ventilación de alta frecuencia

M.J. Solana, Jesús López Herce Cid, J. Urbano Villaescusa, S. Mencía Bartolomé, J. del Castillo, José M. Bellón Cano

• Objective To ascertain whether a spirometer can measure tidal volume (TV) during high frequency oscillatory ventilation (HFOV) and high frequency jet ventilation (HFJV), and to analyse the effect of changes in ventilator settings.

  Methods The study was performed with paediatric porcine lung models submitted to HFOV with a Sensormedics 3100 ventilator and HFJV with a Paravent PateR ventilator connected to a D-Fend spirometer. Programmed frequency, amplitude, and mean airway pressure (MAP) were changed in the ventilator, and TV and pressures were recorded using the spirometer.

  Results The spirometer measured TV in the paediatric lung models and piglets, but could not measure TV less than 8ml, when the pressure amplitude was higher than 55cmH2O or the MAP was higher than 30cmH2O. With HFOV there was a correlation between amplitude and tidal volume, and a positive correlation between pressure and TV with HFJV. With both respirators there was a negative correlation between frequency and TV.

  Conclusions The D-Fend spirometer can measure tidal volume and pressure during HFOV and HFJV. However, it does not work with volumes lower than 8ml, and high amplitude or mean airway pressure.