Influence of Personalized Lung Volume Optimization Maneuver on Lung Function and Cardiac Performance in Children

The goal of this randomized interventional clinical trial is to learn if a standardized lung volume optimization maneuver (LVOM) is beneficial in 1. study) children undergoing biventricular repair of their congenital heart disease (CHD) with cardiopulmonary bypass and 2. study) in children with severe respiratory failure at risk for or need for ECMO. The main questions it aims to answer are: Main hypotheses of CHD study: Does a standardized PEEP-Titration maneuver, to optimize end-expiratory lung volume improve: * cardiac performance * lung function Does it make a difference in: * length of ventilation * ventilation/perfusion mismatch of the lung * need for vasopressor support? Main hypotheses of ECMO study: Does a LVOM in children/infants with severe respiratory failure /ARDS * improve lung compliance and gas exchange * facilitate lung protective ventilation according to PALICC-2 guidelines * improve lung aeration and V/Q-matching assessed with EIT Does it make a difference in * need for ECMO * duration of ECMO runs * hemodynamics stability