Clinical and economic effects of an antimicrobial stewardship intervention in a surgical intensive care unit.

To study the effects of an Antimicrobial Stewardship (AMS) programme designed as a once-weekly "Prospective Audit with Feedback and Intervention" in a surgical intensive care unit. Retrospective, pre-/post-observational comparison of antimicrobial drug use, patient safety, and cost of care. During the 12-month AMS period the consumption of antimicrobials dropped by 18.3%. While the consumption of broad-spectrum antibiotics decreased by 17.4% the consumption of narrow spectrum penicillins increased by 89.9%, reaching 26.3% of the total antibiotic consumption. Treatment outcomes and rates of Clostridioides difficile infections before and during the programme were not significantly different. The reduction in antimicrobial costs of 46,393€ was offset by an expenditure of 8,047€, for both human resources and additional radiological procedures, resulting in a net saving of 38,346€. 92% of the antibiotic related savings were due to the reduced use of tigecycline and linezolid, and decreases in drug retail prices. AMS programmes can both reduce the consumption of antimicrobials and modify their spectrum in intensive care without negatively affecting treatment outcomes. The resulting cost savings are negligible. The incentive to implement such programmes cannot, therefore, be immediate institutional cost savings, but should be rather the long-term goal of reducing antibiotic resistance, and its consequences, in terms of long-term health care costs.