The effects of Ringer's acetate, 6% dextran-70, 7.5% NaCl, and the combination of 7.5% NaCl and dextran-70 were tested in resuscitation from endotoxin shock induced by continuous iv infusion of Escherichia coli endotoxin in pigs. After about 3 h, a reproducible shock state was achieved and treatment was started, governed by the left atrial pressure. The hypertonic solutions (7.5% NaCl and 7.5% NaCl in dextran-70) did not show any overall advantages over the isotonic solutions (Ringer's acetate and dextran-70). Only transient beneficial hemodynamic effects lasting less than 30 min after infusion were seen. When dextran-70 was administered, cardiovascular function was markedly improved and oxygen delivery (DO2) and survival were significantly higher compared with the crystalloid groups (Ringer's acetate and 7.5% NaCl). Administration of large amounts of Ringer's acetate resulted in an immediate deterioration of pulmonary function. It was difficult to elevate left atrial pressure or even to keep it at baseline level, and cardiac index was only transiently increased. The overall result was a deterioration of DO2 and poor survival compared with the dextran-70 treated pigs. We conclude that dextran-70 is superior to Ringer's acetate in resuscitation from endotoxin-induced shock in pigs. Furthermore, we found no role for the use of hypertonic saline, alone or in combination with dextran, in the treatment of this type of prolonged endotoxin shock.