Bariatric Electrical Impedance Tomography

Thoracic electrical impedance tomography measurements ( min each) will be performed at the following time points: before induction of the anaesthesia; before the surgical procedure when the induction is terminated and recruitment manoeuvers have been performed; after the termination of the surgical procedure; before transport to the Post anaesthesia Care Unit (PACU); before the discharge from the PACU after 2 hours of monitoring. An additional thoracic EIT-measurement will be performed before discharge at home. For this, resulting potential differences are measured, and impedance distribution sampled at 30 Hz will be calculated. Relative change in poorly ventilated lung regions (silent spaces) and end-expiratory lung impedance (EELI) and measures of ventilation inhomogeneity will be calculated using customised code (Matlab R2021a, The MathWorks, Nattick, Massachusetts, USA).