Observations on vancomycin use in U.S. hospitals

Abstract

Current knowledge and policies regarding vancomycin use and the clinical performance of vancomycin in U.S. hospitals were assessed. A questionnaire was sent to interested hospital pharmacists. An observational study of hospitalized adults who received at least 72 hours of i.v. vancomycin for a culture-confirmed gram-positive infection followed. Hospital antibiograms were obtained for gram-positive susceptibility data. A total of 59 respondents completed the survey. Survey results revealed that vancomycin is rarely restricted. Investigators from 24 hospitals, 16 (67%) of which were teaching facilities, collected retrospective data from the records of 200 patients. Infection sites included blood, lower respiratory tract, and skin and soft tissue. Staphylococcus aureus was isolated from 52% of positive cultures; 75% of these were methicillin-resistant S. aureus (MRSA). Serum vancomycin concentrations were monitored in 95% of patients; results from 22 hospitals were evaluable. Trough serum vancomycin concentrations were higher in teaching versus nonteaching hospitals (p < 0.001). Peak serum vancomycin concentrations were also higher in teaching versus nonteaching hospitals (p < 0.05). Clinical responses from 22 hospitals were evaluable; the mean success rate of 82% did not significantly differ between teaching and nonteaching hospitals. Vancomycin- associated adverse events occurred in 13 patients (6.5%) and were reported more frequently for patients in teaching versus nonteaching hospitals (p = 0.02). Observational data suggest that vancomycin remains an effective antibiotic with infrequent discontinuations due to adverse events, and trough serum vancomycin concentrations are monitored routinely. Antibiogram data revealed that the prevalence of MRSA continues to increase.