DSP and empyema: The average intrapleural concentration of DSP 40 min after treatment with 2.0 mg/kg increases from 10 μg/mL in TCN‐induced injury to 36 μg/mL in empyema and increases further to >300 μg/mL after a dose escalation to 8.0 mg/kg DSP, with which PAI‐1‐TFT is successful (Figure 4; green symbols).