[Evaluation of prescription of antibiotics in an intensive care unit].

Objectives: In order to optimize prescriptions, we conducted a qualitative evaluation of antibiotic prescription in an intensive care unit.

Methods: A prospective observational study was performed on 100 consecutive prescriptions from 11/95 to 4/96.

Results: Among 14 documented cases, initial antibiotic therapy was in accordance with antimicrobial susceptibility patterns in all but one case. Among 86 empirical cases, 38 were secondarily documented, yielding 43 microorganisms. Of these 38, 27 were susceptible to 2 or more empirical antibiotics, 3 to only 1 and 8 to none. Antibiotics were modified in 23/38 (60%) cases, resulting in drug changes (n = 21) or drug addition (n = 2). In all cases, the new prescription was consistent with the antibiogram. In the 48 cases where no microorganism was isolated, antibiotic change was guided by clinical course and occurred in 6 (12.5%) cases. A switch to older, cheaper or more narrow spectrum antibiotics was possible in 18 cases, but was actually done in only 4 (22%). Dosage errors were observed in 5 cases of initial therapy. Second line therapy contained 8(21%) dosage errors. Most frequently, isolated organisms at admission were: Staphylococcus sp. (n = 15), P. aeruginosa (n = 11) and S. pneumoniae (n = 10). New pathogens emerged in 16 patients (16%) receiving antibiotics. The most frequent was P. aeruginosa in 4 patients receiving ofloxacin + amoxicillin +/- clavulanic acid.

Conclusion: These results are encouraging, however, the use of guidelines and periodic evaluation of antibiotic prescription practices might improve the efficiency of empirical antibiotic prescriptions and reduce overall antibiotic costs.