Treatment of methicillin-resistant Staphylococcus aureus ventilator-associated pneumonia with high-dose vancomycin or linezolid

Abstract

The purpose of this study was to determine the clinical cure rate of high-dose vancomycin for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) ventilator-associated pneumonia (VAP) in critically ill trauma patients. Recent trials suggest that a traditional dose of 1 g q12 hours results in unacceptable cure rates for MRSA VAP. Thus, more aggressive vancomycin dosing has the potential to improve efficacy. Based on pharmacokinetic principles, the goal initial dose at the study center has been 20 mg/kg q12 hours or q8 hours since the 1990s. All patients admitted to the trauma intensive care unit from 1997 to 2008 diagnosed with MRSA VAP were retrospectively reviewed. Diagnosis required bacterial growth ≥ 100,000 colony forming units/mL from a bronchoscopic bronchoalveolar lavage, new or changing infiltrate, plus at least two of the following: fever, leukocytosis or leukopenia, or purulent sputum. Overall, 125 patients with 141 episodes of MRSA VAP were identified. Mean age was 47 years ± 21 years, median Injury Severity Score was 29 (22-43), 70% of patients were male, and the mean length of intensive care unit stay was 38 days ± 35 days. The mean initial vancomycin dose was 18.1 mg/kg/dose with a mean duration of therapy of 11 days. Clinical success was achieved in 88% (125 of 131) of episodes, with microbiological success in 89% (66 of 74) of episodes with a follow-up bronchoscopic bronchoalveolar lavage. Overall mortality was 20% (25 of 125), with death due to VAP in 12 of 25 deaths. Mean initial vancomycin trough concentrations were 10.6 mg/L in the clinical success group and 13.3 mg/L in the clinical failure group (p = not significant). High-dose vancomycin provided an acceptable cure rate for MRSA VAP in critically ill trauma patients. Therapeutic study, level III.