Effects of combined high-dose partial liquid ventilation and almitrine on pulmonary gas exchange and hemodynamics in an animal model of acute lung injury

Objectives: To determine possible additive effects of combined high-dose pa rtial liquid ventilation (PLV) and almitrine bismesylate (ALM) on pulmonary gas exchange and hemodynamics in an animal model of acute lung injury (ALI ). Design and setting: Prospective, controlled animal study in an animal resea rch facility of a university hospital. Interventions: ALI was induced in 12 anesthetized and mechanically ventilat ed pigs by repeated wash-out of surfactant. After initiation of PLV with 30 ml/kg perfluorocarbon the animals were randomly assigned to receive either accumulating doses of ALM (0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 mug/kg per mi nute) for 30 min each (n= 6) or the solvent malic acid (n = 6). Measurement and results: Pulmonary gas exchange and hemodynamics were measu red at the end of each infusion period. Compared to ALI, PLV alone signific antly increased arterial oxygen partial pressure (PaO2) and decreased venou s admixture (Q(VA)/Q(T)) and mean pulmonary artery pressure (MPAP). Adminis tration of ALM did not result in a further improvement in PaO2, Q(VA)/Q(T) or MPAP compared to PLV alone but decreased PaO2 and increased Q(VA)/Q(T) a nd MPAP when 16 mug/kg per min ALM was compared to PLV alone. Conclusions: In an animal model of surfactant depiction induced ALI the com bined treatment of PLV and ALM induced no significant improvement in pulmon ary gas exchange or hemodynamics when compared to PLV alone. Moreover, high -dose ALM significantly impaired gas exchange and pulmonary hemodynamics.