A prospective trial of 6% hetastarch (HES) v 5% plasma protein fraction (PPF) as the colloid component of intravenous (IV) fluid resuscitation was conducted in 32 patients with multisystem trauma and/or hemorrhagic shock. Patient age, mechanism and pattern of injury, and IV fluid requirements were similar in both groups. No intergroup differences were noted in indexes of hepatic, pulmonary, or renal function or in the incidence of infection. The frequency of other complications, including bleeding diatheses, and mortality were identical in the two groups. Although this investigation should be viewed as a pilot study, our results suggest that, compared with PPF, HES in large volumes is a safe, effective colloid solution in the resuscitation of patients with multisystem trauma and/or hemorrhagic shock. Further study of HES in a larger number of patients is warranted by these findings.