A system and method for determining a potential lung recruitment value for a patient that includes during an applied first positive end expiratory pressure (PEEP) to the lungs of the patient, measuring a first end expiratory lung impedance (EELZ) of the lungs at the first PEEP； during an applied second PEEP, measuring a second EELZ at the second PEEP, determining a change in EELZ between the first PEEP and the second PEEP, determining a first chord-compliance of the lungs from pixels of a first electrical impedance tomography (EIT) image of the patient at the first PEEP, determining a second chord-compliance from a second EIT image of the patient at the second PEEP, determining a first index representing the change in EELZ, determining a second index representing a change in compliance, and based on the first index and the second index, determining a potential lung recruitment value for the patient.
