Background: The aim of this study was to evaluate the possible presence of diastolic dysfunction and its possible effects in terms of respiratory mechanics, gas exchange and lung recruitability in mechanically ventilated ARDS.
Methods: Consecutive patients admitted in intensive care unit (ICU) with ARDS were enrolled. Echocardiographic evaluation was acquired at clinical PEEP level. Lung CT-scan was performed at 5 and 45 cmH2O. In the study, 2 levels of PEEP (5 and 15 cmH2O) were randomly applied.
Results: A total of 30 patients were enrolled with a mean PaO2/FiO2 and a median PEEP of 137 ± 52 and 10 [9-10] cmH2O, respectively. Of those, 9 patients (30%) had a diastolic dysfunction of grade 1, 2 and 3 in 33%, 45% and 22%, respectively, without any difference in gas exchange and respiratory mechanics. The total lung weight was significantly higher in patients with diastolic dysfunction (1669 [1354-1909] versus 1554 [1146-1942] g) but the lung recruitability was similar between groups (33.3 [27.3-41.4] versus 30.6 [20.0-38.8] %). Left ventricular ejection fraction (57 [39-62] versus 60 [57-60]%) and TAPSE (20.0 [17.0-24.0] versus 24.0 [20.0-27.0] mL) were similar between the two groups. The response to changes of PEEP from 5 to 15 cmH2O in terms of oxygenation and respiratory mechanics was not affected by the presence of diastolic dysfunction.
Conclusions: ARDS patients with left ventricular diastolic dysfunction presented a higher amount of lung edema and worse outcome.
Keywords: ARDS; left ventricular diastolic dysfunction; total lung weight.