Hypothesis
Antibiotic regimens containing aminoglycosides result in a similar outcome compared with nonaminoglycoside regimens in the treatment of gram-negative infections in surgical patients.
Design
An inception cohort study of hospitalized surgical patients from December 1, 1996, through September 30, 1998. Patients were observed from the time of diagnosis of infection to discharge.
Setting
University hospital.
Patients
Two hundred fifty-eight consecutive gram-negative infections occurring in general surgical and trauma patients and patients undergoing transplantation. Sixty-six patients received aminoglycosides as a component of their treatment regimen, whereas 192 received other agents.
Results
Patients treated with aminoglycosides were younger (mean ± SEM age, 48 ± 2 vs 53 ± 1 years; P = .04 by univariate analysis) and had a similar APACHE II (Acute Physiology and Chronic Health Evaluation II) score (mean ± SEM, 17 ± 1 vs 15 ± 1; P = .10), yet had a significantly higher mortality vs patients treated with other agents (29% vs 14%; P = .02). A larger proportion of patients requiring hemodialysis were treated with aminoglycosides (33% vs 13%; P = .001). Although there was no difference in the sites of infection between groups, surgical patients with gram-negative pneumonia had a higher mortality when treated with aminoglycosides (37% vs 18%; P = .04), despite similar APACHE II scores (mean ± SEM, 20 ± 1 vs 18 ± 1; P = .40).
Conclusions
Despite a younger age and similar severity of illness, patients with gram-negative infections treated with aminoglycosides were associated with a higher mortality rate, although this may be related to selection bias in the use of aminoglycoside agents. The mortality rate associated with gram-negative pneumonia was also higher in patients treated with aminoglycosides, despite a similar severity of illness. Future randomized studies are necessary to reanalyze the role of aminoglycosides in treating surgical patients with gram-negative infections, particularly pneumonia.