Fig. 1.

Experimental design. Twenty-four rabbits with acute respiratory distress syndrome (ARDS) were enrolled and stratified into two groups based on their received driving pressure (DP): a high DP group and a low DP group. Ventilation was performed using a pressure control model, with rabbits subjected to 30 cmH2O and 15 cmH2O driving pressures for 60 min. Following the initial ventilation period, a 10 mL/kg saline solution was administered via intravenous injection, leading to an elevation in central venous pressure from 2–4 mmHg to 8–10 mmHg. Subsequently, rabbits underwent an additional 60 min of ventilation. At the experiment's end, rabbits were sacrificed, and lung tissue specimens were collected for further analysis. Blood samples were obtained at three key timepoints: before the induction of ARDS, before fluid loading, and after 120 min of ventilation. ARDS, acute respiratory distress syndrome; DP, driving pressure; PC, pressure control; CVP, central venous pressure