Meropenem administration by intermittent infusion versus continuous infusion for the treatment of nosocomial pneumonia

Objective

Mainly, beta-lactamic 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 carbapenems by continuous infusion maintain constantly concentrations above the MIC of susceptible organisms over the course of therapy; but limited data exist on clinical efficacy (only occasional observations have been made). The purpose of this study was to evaluate the clinical efficacy of meropenem by continuous infusion administration (CI) or by intermittent infusion (II) for the treatment of ventilator-associated pneumonia (VAP) caused by Gram-negative bacilli (GNB).

Methods

An historic control group (1 July 2000–20 June 2002) with VAP caused by GNB who received initial empiric antibiotic therapy with meropenem by II (n = 18) was compared with a prospective cohort of patients (1 July 2002–30 June 2003) treated with meropenem by CI (n = 10), at a university hospital medical–surgical ICU. VAP were treated during 14 days with two antibiotics: meropenem (1 g/6 hours intravenously) plus another (aminoglycoside or quinolone). Antibiotic clinical effect was categorized as cure or failure. Differences between groups were tested by means of Student's t test and exact chi-square by permutation, using Statxact Software 5.0. We consider values P < 0.05 as a significant difference.

Results

Significant differences were not found between both groups of patients (15 with CI and 30 with II) in sex, age, APACHE II score, diagnosis, microorganism responsible and organ dysfunction severity assessed by the Sepsis-related Organ Failure Assessment score. The CI group showed significantly greater clinical cure than the II group (CI, 14/15 [93.33%] vs II, 19/30 [63.33%], P = 0.038) and smaller, but not significant, attributable mortality to VAP (1 of 15 [6.66%] vs 7 of 30 [23.33%], P = 0.236).

Conclusions

Our data suggest that administration of meropenem by CI may have more clinical efficacy than administration by II for the treatment of nosocomial pneumonia, but more studies are required to confirm it.