Background Therapeutic de-escalation enables us to improve the effectiveness of empirical antimicrobial therapy and avoids the development of resistance.

Purpose To analyse the preliminary results of a pilot project of pharmacy interventions to achieve de-escalation of treatment with carbapenems, within a programme of optimisation of antibiotics use.

Materials and Methods Prospective study of pharmacy interventions aimed at de-escalation in patients starting treatment with carbapenems, over three months (from March to June 2012) in a tertiary hospital, based on available microbiology results. The de-escalation suggestion was made through the electronic prescribing software. The variables analysed were: number of patients prescribed carbapenems, prescribing speciality, request for cultures, microorganisms isolated and interventions performed. De-escalations carried out without pharmacy intervention were also assessed.

Results Total number of prescriptions was 433. The most prescribed carbapenem was ertapenem (37.6%) followed by meropenem (36%). The carbapenem most used in Internal Medicine was meropenem (58.2%) and in Urology, imipenem (75%). Ertapenem was used more frequently in General Surgery (53.7%) and Vascular Surgery (86.0%). Out of a total of 316 requested tests, 172 (54.4%) were positive. The most common pathogen isolated was Escherichia Coli (24.7%) 20.8% of which were Extended-Spectrum Beta-Lactamase (ESBL)-producing, 60% of which were sensitive to piperacillin-tazobactam or fosfomycin. Klebsiella spp. were isolated in 3.6%, of which 33.3% were ESBL-producing and 50% were sensitive to piperacillin-tazobactam. Total treatments subject to de-escalation were 96 (55.8%), out of 172 showing this possibility, where 74 (77.1%) were carried out by initiatives of medical teams and 22 (22.9%) after pharmacy interventions. The Services with a higher degree of acceptance of pharmacy interventions were Internal Medicine (36.4%) and General Surgery (27.3%).

Conclusions Although the therapeutic de-escalation of empirical treatments with carbapenems was a low percentage, nevertheless pharmacy interventions achieved an increase of this practise, with the more receptive specialties being Internal Medicine and General Surgery.

No conflict of interest.