Factors increasing the risk of infection in patients with open fractures.

A study was undertaken to determine what factors are important in determining whether or not a patient with an open fracture will develop an infection. Debrided tissue was cultured to determine quantitative bacterial counts. The patients' subsequent records were evaluated and the infection rate correlated with culture data and other factors that might be associated with development of infection. Of the 70 patients evaluated, 13 (19%) became infected. When the infection rate was correlated with the use of fixation devices, it was found that 1/19 (5%) of the patients with no implants, 3/16 (19%) of the patients with external fixation devices, and 9/35 (26%) of the patients with internal fixation became infected. Most of the infections were caused by Gram-negative bacteria. There was little correlation between the bacterial counts in the first piece of tissue taken at debridement and the development of infection. There was significant correlation between the bacterial count in the last piece of tissue taken at debridement and the development of infection. Thus the infection was correlated with what was in the tissue when the patient left the operating room and not with what was in the tissue when the patient entered the operating room.