Abstract:

Objective To investigate the effects of adaptive support ventilation (ASV) plus lung recruitment maneuvers (LRM) on acute respiratory distress syndrome (ARDS). Methods Twenty-eight patients with ARDS after trauma were collected, and were randomly treated with ASV or intermittent positive pressure ventilation (IPPV) after management with IPPV for 8 h. The minute ventilation in ASV was the same with IPPV. Positive end expiratory pressure (PEEP) level increased in each model by 0, 5 and 10 cmH2O, and each level of PEEP was maintained for 60 min. LRM was added to each PEEP level in ASV model (ASV+LRM model). Three hours after the previous ventilation model, it was adjusted to IPPV with 0 cmH₂O PEEP, then to the other model 1 h later. Hemodynamics, respiratory mechanics and oxygen metabolism parameters were measured with Swan-Ganz catheter, electrocardiogram monitor and breathing machine after patients were ventilated with each level of PEEP for 50 min. Results Under the same PEEP level, there was no significant difference in hemodynamic parameters between ASV+LRM model and IPPV model (P>0.05), while the peak inspiratory pressure in ASV+LRM model was significantly lower than that in IPPV model (P<0.05), and lung dynamic compliance, partial pressure of oxygen in artery and oxygen delivery in ASV+LRM model were significantly higher than those in IPPV model with PEEP=5 cmH₂O (P<0.05). Conclusion ASV+LPS model is better than IPPV in ventilation for patients with ARDS.

Key words: respiratory distress syndrome, intermittent positive pressure ventilation, adaptive support ventilation, lung recruitment maneuvers