At present, there is a lack of practical and effective methods to evaluate lung recruitment maneuver in patients with acute respiratory distress syndrome (ARDS) in the clinic.

To evaluate the potential of inflammatory factors (IF) from bronchoalveolar lavage fluid (BALF) for lung recruitment maneuver (RM) in patients with ARDS.

Sixty-two ARDS patients requiring invasive mechanical ventilation in ICU at Affiliated Jinhua hospital of Zhejiang University School of Medicine from March 2020 to March 2022 were included for the study. The levels of IL-6, IL-8, IL-10 in BALF, lung ultrasound score (LUS) and oxygenation index (PaO₂/FiO₂) , which were monitored before and on the 3rd day after the RM. According to the differences in LUS (ΔLUS) before and after RM, patients were divided into RM effective group (RM-E group) with the value greater than 5 points and RM inactive group (RM-N group) with the value less than 5 points, and the changes of IF in BALF were compared between the two groups; the correlations between ΔIF, differences of IF between the two groups before and after RM, and ΔLUS (ΔIL-6, ΔIL-8, ΔIL-10 and ΔLUS) were analyzed. The ROC was used to calculate the predictive value of IF in BALF for the potential of RM.

The study enrolled 38 patients in the RM-E group and 24 in the RM-N group. There was no statistical difference in the levels of IL-6, IL-8 and IL-10 in BALF and LUS between the two groups before RM (P>0.05) . There was also no significant difference in tidal volume (VT) , positive end expiratory pressure (PEEP) , plateau pressure (P_plat) , fraction of inspiration O₂ (FiO₂) and PaO₂/FiO₂ between the two groups (P>0.05) . The levels of IL-6, IL-8, IL-10 in BALF and PaO₂/FiO₂ before and after RM in the two groups were statistically significant (P<0.05) . There was significant difference in LUS before and after RM in RM-E group (P<0.05) , but no significant difference in LUS before and after RM in RM-N group (P>0.05) . After RM, the difference of ΔIL-6, ΔIL-8, ΔIL-10 and ΔLUS was statistically significant in the two groups (P<0.05) . Correlation analysis showed that ΔIL-6 and ΔLUS had a significant positive correlation (P<0.05) , while ΔIL-8, ΔIL-10 and ΔLUS had no significant correlation (P>0.05) . The area under the curve (AUC) predicted RM potential by ΔIL-6 in patients with ARDS was 0.794, the sensitivity was 94.7%, and the specificity was 70.8%.

The detection of IF in BALF, especially IL-6, has a certain clinical value in evaluating the lung recruitment maneuver potential in patients with ARDS.