RESUMEN
OBJECTIVE: To assess the protective effect of prostaglandin E1 liposome (lipo-PGE1) on acute lung injury (ALI) in a porcine model of ALI. METHODS: The ALI model was reproduced by lipopolysaccharide (LPS) intravenous instillation and high tidal volume ventilation. A total of 16 domestic pigs were randomized to receive lipo-PGE1 (n=8) or placebo (n=8). Parameters of haemodynamics and pulmonary gas exchange were monitored through pulmonary artery catheter and blood gas analysis at baseline and 2, 3, 4 and 5 hours after LPS instillation. The inflation quasi-static pressure-volume (P-V) curve was obtained by ventilator occlusion technique, and the P-V data sets were fit with sigmoidal equation in order to define and compare the respiratory mechanics in animals of two groups. Plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-8 (IL-8) were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: There was a decrease in cardiac index (CI) and mean arterial pressure (MAP) in control group compared with those in the group who received lipo-PGE1. In the group receiving lipo-PGE1 the parameter of oxygenation, including partial pressure of oxygen in arterial blood (PaO(2)), oxygenation index (PaO(2)/FiO(2)), and alveolar-arterial oxygen difference (A-aDO(2)) were significantly improved (all P<0.05) and pulmonary shunt (Qs/Qt) associated with lung injury was also significantly reduced (P<0.05) compared with control group. The respiratory mechanics (including lower and upper inflection point) in the group given lipo-PGE1 were better than those of control group (all P<0.05). Plasma levels of TNF-alpha and IL-8 were found to rise in both groups, but the rise in TNF-alpha and IL-8 in the group in which lipo-PGE1 was given were lower with shorter period compared with control group(all P<0.05). CONCLUSION: Intravenous delivery of lipo-PGE1 significantly attenuate ALI caused by LPS instillation and high tidal ventilation, and it also shows beneficial effects on haemodynamics.