A process adjusts a ventilation parameter (40) for a ventilation process (90) of a patient (110), which is carried out by a ventilator (20). Electrical impedance tomographic (EIT) data (70) of the lungs (111) of the patient (110), concerning the ventilation process (90), are collected by an EIT device (30). An adjusting device (1), adjusting a ventilation parameter (40) for the ventilation process (90), has an analysis unit (2) with a memory (3), a data input unit (5) data-communicatingly connected to the analysis unit (2) for receiving data and a data output unit (7) data-communicatingly connected to the analysis unit (2) for outputting data. A medical system (100), includes a ventilator (20), an EIT device (30) as well as the adjusting device (1) for adjusting a ventilation parameter (40) for the ventilation process (90) of a patient (100).
