Dynamic Relative Regional Lung Strain Estimated by Electrical Impedance Tomography in an Experimental Model of ARDS

To analyze the role of PEEP on dynamic relative regional strain (DRRS) in a model of ARDS, respective maps were generated by electrical impedance tomography (EIT).Eight ARDS pigs submitted to PEEP steps of 0, 5, 10, and 15 cm HAt constant ventilation, respiratory compliance increased progressively with PEEP (lowest value at zero PEEP 10 ± 3 mL/cm HEIT-derived DRRS maps showed high strain in ventral lung zones at low levels of PEEP. The findings suggest overdistention of the baby lung.