Personalized positive end-expiratory pressure in spontaneously breathing patients with acute respiratory distress syndrome by simultaneous electrical impedance tomography and transpulmonary pressure monitoring: a randomized crossover trial

Personalized positive end-expiratory pressure (PEEP) might foster lung and diaphragm protection in patients with acute respiratory distress syndrome (ARDS) who are undergoing pressure support ventilation (PSV). We aimed to compare the physiologic effects of personalized PEEP set according to synchronized electrical impedance tomography (EIT) and driving transpulmonary pressure (∆PL) monitoring against a classical lower PEEP/FiO 2 table in intubated ARDS patients undergoing PSV. A cross-over randomized multicenter study was conducted in 30 ARDS patients with simultaneous recording of the airway, esophageal and transpulmonary pressure, together with EIT during PSV. Following a decremental PEEP trial (18 cmH 2 O to 4 cmH 2 O), PEEP EIT-∆PL was identified as the level with the smallest difference between lung overdistension and collapse. A low PEEP/FiO 2 table was used to select PEEP TABLE . Each PEEP strategy was applied for 20 min, and physiologic data were collected at the end of each step. The PEEP trial was well tolerated. Median PEEP EIT-∆PL was higher than PEEP TABLE (10 [8–12] vs. 8 [5–10] cmH 2 O; P = 0.021) and, at the individual patient level, PEEP EIT-∆PL level differed from PEEP TABLE in all patients. Overall, PEEP EIT-∆PL was associated with lower dynamic ∆PL ( P < 0.001) and pressure–time product ( P < 0.001), but there was variability among patients. PEEP EIT-∆PL also decreased respiratory drive and effort ( P < 0.001), improved regional lung mechanics ( P < 0.05) and reversed lung collapse ( P = 0.007) without increasing overdistension ( P = 0.695). Personalized PEEP selected using synchronized EIT and transpulmonary pressure monitoring could be associated with reduced dynamic lung stress and metabolic work of breathing in ARDS patients undergoing PSV.