Setting PEEP in patients with COVID-19-related-ARDS: a physiological comparison between methods

Background: Several PEEP approaches in COVID-19 ARDS exist, but the optimal method and impact on transpulmonary pressure (PL), overdistension and collapse is unclear. Objective: Compare electrical impedance tomography (EIT) based methods (i.e., crossing point (EITCP), after crossing point (EITACP), low collapse 0 cmH2O (PL,EE). Methods: Post-hoc analysis of 29 patients from two ICUs, with EIT and esophageal pressure measured during PEEP trials. We compared the PEEP, PL,EE, overdistension and collapse at the method’s suggested PEEP. Results: EITCP resulted in higher PEEP (in cmH₂O) (14 [12–16]) than EITACP (12 [10–14]) and PL,EE (12 [8–14]). EITLC(14 [10–16]) and CRS (12 [10–14]) were intermediate. PL,EE (in cmH₂O) at suggested PEEP was higher with EITCP (2.7 [0.1–5.8]) vs EITACP (1.6 [–1.8–4.6]) and PL,EE (1.4 [0.6–2.1]). Collapse was lowest with EITCP (3.0 [2.0–4.0]%) and EITLC (3.4 [2.7–4.1]%) and highest with PL,EE (5.4 [2.0–12.0]%), while overdistension did not differ (Figure). Targeting PL,EE>0 caused 51% of patients to show high or extreme overdistension or collapse. Conclusion: EITCP yields slightly higher PEEP and PL,EE than targeting PL,EE >0, with less collapse but not more overdistension. EIT-based methods better protect against extremes of overdistension or collapse. erjor;12/suppl_17/120/F1 F1 F1