Inflammatory lung edema correlates with echocardiographic estimation of capillary wedge pressure in newly diagnosed septic patients

PURPOSE: Lung ultrasound is an accurate and accessible tool to quantify lung edema. Furthermore, left ventricle filling pressures (LVFP) can be assessed with transthoracic echocardiography (TTE) by the E/e' ratio (E/e'). The present study aimed to assess the correlation between E/e' and lung edema quantified by a simplified lung ultrasound score (LUS) in newly admitted septic patients.

MATERIALS AND METHODS: In this prospective observational cohort, septic adult patients admitted at the emergency department of a tertiary hospital were included. LUS consisted of four different patterns of lung edema (from normal aeration to parenchymal consolidation). To compare lung edema with LVFP, E/e' was calculated immediately before or within 5min of fluid therapy.

RESULTS: Fifty patients were enrolled in 3months. The LUS correlated with E/e' (r=0.58, P<0.0001). The LUS also increased among E/e' quartiles (Q) (Q1: E/e'≤4.49; Q2: 4.49<E/e'≤5.49; Q3: 5.49<E/e'≤7.11; Q4: >7.11; P=0.0003 for Q1 and 4; 2 and 4); and LUS was significantly higher in abnormal (≥8) vs. normal (<8) values of E/e' (11.29 vs 8.49, P=0.007).

CONCLUSION: In newly admitted septic patients, lung edema is positively correlated with LVFP prior to fluid therapy. This finding might help find future targets for fluid resuscitation in sepsis.