Improving the process of antibiotic therapy in daily practice: interventions to optimize timing, dosage adjustment to renal function, and switch therapy.

BACKGROUND Timely administration of the first dose, dosage adjustment to renal function, switch from intravenous to oral administration, and streamlining are important aspects of rational antibiotic prescription. The goals of this study were to investigate all of these variables, compare them with predefined quality standards, and implement improvement with specific interventions. METHODS At the departments of internal medicine, surgery, and neurology and the emergency department of a tertiary referral university medical center, all consecutive patients receiving therapeutic antibiotics were enrolled. Dosages, timing of first doses, dosing intervals, administration routes, and adjustment of the chosen drug to clinical data were investigated. After the preintervention period, barriers to change were identified, followed by specific interventions and a postintervention measurement. RESULTS In the preintervention and postintervention periods, 247 and 250 patients were enrolled, receiving 563 and 598 antibiotic prescriptions, respectively. The mean time from the order to first dose at the wards improved from 2.7 to 1.7 hours in potentially severe cases (P =.003). Dosage adjustment to renal function remained unchanged at 45% vs 52% (P =.09) of cases where necessary. Switching of therapy from intravenous to oral improved from 46% to 62% (P =.03) and was performed a mean of 1.6 days earlier (P =.002). Streamlining was performed correctly in most cases, and thus no interventions were necessary. CONCLUSIONS Timing of antibiotic therapy and switch therapy may be improved with a combination of interventions. To improve poor adjustment of dosing to renal function, other strategies are needed. In our setting, streamlining was already correct in most cases.