A series of dogs was given massive fluid infusions at two dose levels, 60 cc/kg and 100 cc/kg. The dogs were prepared in three ways: shock induced by bleeding; intravenous injection of oleic acid; and combined oleic acid injection and shock. The studies showed that type of injury was a more important determinant of lung dysfunction than the fluid dose. Shock animals were not hurt by fluid infusion; in oleic acid-injected dogs, the fluid infusion magnified the effect of oleic acid. When shock, oleic acid, and high fluid dose were combined, all animals died. The animals that died had high pulmonary artery diastolic pressures.