Outcome evaluation of an intervention to improve the effective and safe use of meropenem

Background Pharmacists have been involved in promoting the proper and safe use of antimicrobial drugs in our institution since 2010. Setting Kochi Medical School Hospital, Japan. Objective To design and evaluate a plan of administration of meropenem (MEPM) based on its pharmacokinetics and pharmacodynamics, drug sensitivity, bacterial cultures, patient condition and renal function. Method A total of 547 patients admitted between April 2010 and March 2013 with serious infections who were successfully treated with MEPM for three or more days were analysed. Patients were initially divided into two groups according to renal function: group A consisted of patients with mild renal dysfunction [creatinine clearance (CLcr) > 50 mL/min] while group B consisted of patients with moderate to severe renal dysfunction (CLcr ≤ 50 mL/min). These groups were then subdivided into two groups according to the implementation of pharmacist intervention. Main outcome measures Daily dose, frequency of administration, dose interval, duration of therapy, adverse events and cost reduction. Results In the non-intervention subgroup within group A, the daily dose was 1,000 mg/day, the frequency of administration was 1.8 ± 0.6 times/day, and the duration of therapy was 9.4 ± 5.4 days. In the intervention subgroup within group A, the daily dose was 1,500 mg/day, the administration frequency was 2.5 ± 0.6 times/day, and the duration of therapy was 7.4 ± 3.7 days. Although the dose was higher (P < 0.05) and the duration of therapy was an average of 2 days shorter (P < 0.05) in the intervention subgroup, there was no significant difference in the rate of adverse events between the two subgroups. In group B, there were no significant differences between the two subgroups in the daily dose, administration frequency, or duration of therapy. However, liver dysfunction was significantly more common in the non-intervention subgroup than in the intervention subgroup (P < 0.05). The total reduction in drug cost in the intervention groups was estimated to be US$17,490 over 3 years. Conclusion Pharmacist intervention was associated with a shorter duration of therapy, lower drug costs, and decreased adverse effect. We believe that our intervention is beneficial in terms of effectiveness and safety, and supports proper antimicrobial use.