Lung and muscle water after crystalloid and colloid infusion in septic rats: effect on oxygen delivery and metabolism.

We compared the effect of crystalloid infusion with that of colloid infusion on extravascular lung water and muscle water in septic rats. We also examined the relationship of lung and muscle edema to arterial oxygenation and muscle energy metabolism during sepsis. Cecal ligation and perforation were used to induce sepsis. Five animals served as sham-operated controls. Five animals were infused with 0.9% saline solution and five with 10% low molecular weight hydroxyethyl starch (hetastarch). Thermodilution cardiac output, plasma colloid osmotic pressure, and arterial blood gases were sequentially measured over a 6-hour interval. At 6 hours, a biopsy specimen was taken from the rectus femoris and the lungs and adductor magnus muscle harvested for gravimetric analysis (wet-dry/dry weight ratio). The colloid osmotic pressure was 16.1 +/- 1.2 mm Hg in the control animals, 9.3 +/- 0.5 mm Hg in the saline solution-infused animals, and 21.6 +/- 0.5 mm Hg in the hetastarch-infused animals at 6 hours (p less than 0.05 saline vs control, hetastarch). The lung wet-dry/dry weight ratio was 3.46 +/- 0.11 in the control animals, 3.74 +/- 0.13 in the saline group, and 3.64 +/- 0.11 in the hetastarch group (difference not significant). Arterial oxygenation was not significantly different in the three groups. Muscle wet-dry/dry weight ratio was 3.11 +/- 0.16 in the control animals, 2.75 +/- 0.12 in the hetastarch-infused animals, and 3.06 +/- 0.08 in the saline-infused group (not significant). There were no significant differences in skeletal muscle energy production or lactate/pyruvate ratio between the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)