Figure 3

The risk stratification based on HMGB1 and factors related to surgical invasiveness. The cut-off levels of operative time and bleeding volume were 200 min and 155 mL, respectively. When HMGB1 and operative time/bleeding volume were combined, the incidence of postoperative acute exacerbation of interstitial lung disease (AE-ILD) in patients with both HMGB1-high and operative time-long/bleeding volume-high was significantly higher than that in the other two groups (a,b). *P < 0.05, using Pearson’s chi-squared tests.