Outcomes of an intervention to improve hospital antibiotic prescribing: interrupted time series with segmented regression analysis.

OBJECTIVES: To evaluate an intervention to reduce inappropriate use of key antibiotics with interrupted time series analysis. METHODS: The intervention is a policy for appropriate use of Alert Antibiotics (carbapenems, glycopeptides, amphotericin, ciprofloxacin, linezolid, piperacillin-tazobactam and third-generation cephalosporins) implemented through concurrent, patient-specific feedback by clinical pharmacists. Statistical significance and effect size were calculated by segmented regression analysis of interrupted time series of drug use and cost for 2 years before and after the intervention started. RESULTS: Use of Alert Antibiotics increased before the intervention started but decreased steadily for 2 years thereafter. The changes in slope of the time series were 0.27 defined daily doses/100 bed-days per month (95% CI 0.19-0.34) and pound 1908 per month (95% CI pound 1238- pound 2578). The cost of development, dissemination and implementation of the intervention ( pound 20133) was well below the most conservative estimate of the reduction in cost ( pound 133296), which is the lower 95% CI of effect size assuming that cost would not have continued to increase without the intervention. However, if use had continued to increase, the difference between predicted and actual cost of Alert Antibiotics was pound 572448 (95% CI pound 435696- pound 709176) over the 24 months after the intervention started. CONCLUSIONS: Segmented regression analysis of pharmacy stock data is a simple, practical and robust method for measuring the impact of interventions to change prescribing. The Alert Antibiotic Monitoring intervention was associated with significant decreases in total use and cost in the 2 years after the programme was implemented. In our hospital, the value of the data far exceeded the cost of processing and analysis.

Cost-minimization analysis and audit of antibiotic management of bone and joint infections with ambulatory teicoplanin, in-patient care or outpatient oral linezolid therapy.

Bone and joint infections are significant causes of morbidity, mortality and healthcare costs. The cost of treatment for such infections is driven primarily by the length of hospital stay. Many of these infections will require treatment with prolonged periods of parenteral antibiotic therapy. Clinicians and healthcare managers are being attracted increasingly by administering treatment in the ambulatory setting as this offers clinical, economic and quality of life advantages from both the hospital's and patient's perspective. Our retrospective audit of managing 55 treatment episodes of bone and joint infections with teicoplanin delivered in the outpatient or home setting revealed that the mean cost of care per episode of infection was less with treatment in the ambulatory setting ( pound 1749.15) compared with the in-patient setting ( pound 11 400) or compared with the hypothetical situation of treatment with oral linezolid in the home setting ( pound 2546). Teicoplanin therapeutic drug monitoring appears to be valuable in establishing optimal serum levels, which appear to correlate with good clinical outcomes. The potential for alternative day or thrice weekly dosing with teicoplanin may offer further cost advantages whilst maintaining equivalent clinical effectiveness.