This study reviewed all 164 cases of liver trauma seen at the Charity Hospital of New Orleans from 1980 through 1984, in 12 of whom intra-abdominal abscesses formed. Thirty four per cent of the patients had no peritoneal drainage and an abscess rate of 1.8%, 18% had only closed suction drainage and 0% abscess rate, 15% had only open sump drainage and a rate of 8.3%, 14% had only open Penrose drainage with a rate of 8.7%, and 19% had a combination of both open Penrose and sump drainage with a rate of 22.5%. Certain findings or conditions were related to the development of postoperative sepsis. Gunshot wounds were associated with a 9.9% abscess rate, blunt trauma with 3.8%, and stabbings with 0%. Patients who presented in shock were at a threefold increased risk for intra-abdominal abscess formation, those who needed blood transfusions of greater than 6 units were at a tenfold increased risk, those with major liver injuries were at a sixfold increased risk, and those with a total of three or more abdominal organs injured were at a threefold increased risk for abscess formation. There was no significant relation between presence of gastrointestinal perforation and subsequent abscess formation. For patients without the specific risk factors mentioned above, the probability of developing an intra-abdominal abscess is low. This group of patients would therefore benefit little from the presence of a drain, but might very well be harmed by the introduction of external contaminant bacteria into the peritoneal cavity by the drain itself.(ABSTRACT TRUNCATED AT 250 WORDS)