Meropenem by continuous versus intermittent infusion in ventilator-associated pneumonia due to gram-negative bacilli

BACKGROUND: It is known that beta-lactam antibiotics exhibit time-dependent bactericidal activity. Several studies have found continuous infusion of meropenem more effective than intermittent infusion in maintaining constant serum concentrations in excess of the minimum inhibitory concentration. However, limited data exist on the clinical efficacy of meropenern administered by continuous infusion. OBJECTIVE: To evaluate the clinical efficacy of continuous versus intermittent infusion of meropenern for the treatment of ventilator-associated pneumonia (VAP) due to gram-negative bacilli. METHODS: A retrospective cohort study was conducted of patients with VAP caused by gram-negative bacilli who received initial empiric antibiotic therapy with meropenem. We analyzed 2 contemporary cohorts: one group received meropenern by continuous infusion (11 g over 360 min every 6 h), the other by intermittent infusion (11 g over 30 min every 6 h). The administration method was prescribed according to the physician's discretion. Patients received meropenern plus tobramycin for 14 days. RESULTS: There were no significant differences between patient groups with regard to gender, age, APACHE-II at intensive care unit admission, diagnosis, microorganism responsible for VAP, or organ dysfunction severity at the time VAP was suspected. The group receiving medication by continuous infusion showed a greater clinical cure rate than the group treated with intermittent infusion (38 of 42, 90.47%, vs 28 of 47, 59.57%, respectively, with OR 6.44 [95% CI 1.97 to 21.05; p < 0.0011]). CONCLUSIONS: Meropenem administered by continuous infusion may have more clinical efficacy than intermittent infusion.