Piperacillin/tazobactam administered by continuous or intermittent infusion for the treatment of nosocomial pneumonia
© Lorente et al; licensee BioMed Central Ltd. 2009
Published: 13 March 2009
Betalactam efficacy is determined by the duration of time that concentrations remain above the minimum inhibitory concentration (MIC). Some studies have found that the administration of betalactams by continuous infusion maintains constant concentrations above the MIC of susceptible organisms over the course of therapy; but limited data exist on the clinical efficacy of betalactams administered by continuous infusion. The purpose of this study was to evaluate the clinical efficacy of piperacillin/tazobactam by continuous infusion (CI) administration or by intermittent infusion (II) for the treatment of ventilator-associated pneumonia (VAP) caused by Gram-negative bacilli.
A retrospective cohort study (1 June 2002 to 31 December 2007) of patients with VAP caused by Gram-negative bacilli who received initial empiric antibiotic therapy with piperacillin/tazobactam. We analyzed two contemporary cohorts: one received piperacillin/tazobactam by CI (first received a loading dose of piperacillin/tazobactam 4/0.5 g over 30 minutes, and after 4/0.5 g infused over 360 minutes every 6 hours) and the other by II (4/0.5 g over 30 minutes every 6 hours). The administration of piperacillin/tazobactam by CI or II was prescribed according to the physician's discretion.
Significant differences were not found between both groups of patients (37 with CI and 46 with II) in baseline data. Logistic regression analysis showed a higher probability of clinical cure of VAP by CI than by II (33/37 (89.2%) vs. 26/46 (56.5%); OR = 7.4; 95% CI = 1.96 to 37.42; P = 0.001). Logistic regression analysis showed a higher probability of clinical cure of VAP by CI than by II when the microorganism causative of VAP had a MIC of 8 μg/ml (8/9 (88.9%) vs. 6/15 (40.0%); OR = 10.8; 95% CI = 1.01 to 588.24; P = 0.049) and a MIC of 16 μg/ml (7/8 (87.5%) vs. 1/6 (16.7%); OR = 22.9; 95% CI = 1.19 to 1,880.78; P = 0.03); but not when it had a MIC of 4 μg/ml (18/20 (90.0%) vs. 19/25 (76.0%); OR = 2.8; 95% CI = 0.42 to 31.67; P = 0.41).
Administration of piperacillin/tazobactam by continuous infusion may have more clinical efficacy than administration by intermittent infusion for the treatment of nosocomial pneumonia.
This article is published under license to BioMed Central Ltd.