Alveolar overdistension as a cause of lung injury: differences among three animal species.

This study analyses characteristics of lung injuries produced by alveolar overdistension in three animal species. Mechanical ventilation at normal tidal volume (10 mL/Kg) and high tidal volume (50 mL/Kg) was applied for 30 min in each species. Data were gathered on wet/dry weight ratio, histological score, and area of alveolar collapse.

Alveolar fluid clearance in healthy pigs and influence of positive end-expiratory pressure.

Introduction: The objectives were to characterize alveolar fluid clearance (AFC) in pigs with normal lungs and to analyze the effect of immediate application of positive end-expiratory pressure (PEEP).

Methods: Animals (n = 25) were mechanically ventilated and divided into four groups: small edema (SE) group, producing pulmonary edema (PE) by intratracheal instillation of 4 ml/kg of saline solution; small edema with PEEP (SE + PEEP) group, same as previous but applying PEEP of 10 cmH2O; large edema (LE) group, producing PE by instillation of 10 ml/kg of saline solution; and large edema with PEEP (LE + PEEP) group, same as LE group but applying PEEP of 10 cmH2O. AFC was estimated from differences in extravascular lung water values obtained by transpulmonary thermodilution method.

Influence of extravascular lung water determination in fluid and vasoactive therapy.

Introduction: Preload parameters in postresuscitation phase are not sufficiently sensitive to guide fluid therapy in critically ill patients. We analyzed modifications in the fluid therapy and vasoactive drugs of critically ill patients that were produced by inclusion of extravascular lung water (EVLW) data in the treatment protocol and evaluated the short-term response.

Methods: This observational and prospective study included consecutive patients with hypotension or hypoxemia, comparing the therapeutic plan for fluid and vasoactive drug treatment between before and after knowing the EVLW value.

Intratracheal dopamine attenuates pulmonary edema and improves survival after ventilator-induced lung injury in rats.

Introduction: Clearance of alveolar oedema depends on active transport of sodium across the alveolar-epithelial barrier. beta-Adrenergic agonists increase clearance of pulmonary oedema, but it has not been established whether beta-agonist stimulation achieves sufficient oedema clearance to improve survival in animals. The objective of this study was to determine whether the increased pulmonary oedema clearance produced by intratracheal dopamine improves the survival of rats after mechanical ventilation with high tidal volume (HVT).