Background: Measurement of antimicrobial utilization (AMU) is a core activity of hospital antimicrobial stewardship (AS). Few data exist on AMU in Canadian neonatal intensive care units (NICUs). Our objectives were to quantify AMU in 5 of the NICUs in Calgary, Canada over a three-year period; identifying trends in AMU for benchmarking purposes before specific antimicrobial stewardship initiatives were begun.
Methods: We collected data on the type and quantity of all formulary systemic antimicrobials administered to infants in NICUs in Calgary, Canada from 04/01/11 to 03/31/14. Antimicrobial use was quantified by days of therapy (DOT) per 1000 patient days (PD) for each month of the study period. Longitudinal utilization was inspected visually for discernible trends at each site. Number of agents each patient received was calculated as a novel variable to describe the complexity of infectious diseases in the patient population of each unit.
Results: Total average antimicrobial use by NICU (DOT/1000 PD), being predominantly systemic antibacterial agents, was highest at the level 3 nurseries at Hospital A (624.1) and Hospital F (516.0), followed by the level 2 nurseries: Hospital R (250.5), Hospital P (176.7), and Hospital S (155.0). AMU decreased by 26.1% and 23.6% at Hospital P and Hospital F respectively, over the 2012 to 2014 fiscal years. There were no discernible trends of AMU at Hospitals A, R or S. Hospital A had the highest percentage of patients on three or more antimicrobials at a time (47.97%) compared to 17.27%, 6.95%, 7.45%, and 5.35% at Hospitals F, P, R, and S respectively, in the 2014 fiscal year. Gentamicin and ampicillin were the most frequently used agents accounting for 89%, 83%, 79%, 67% and 33% of total AMU at Hospitals S, R, P, F, and A respectively, in the 2014 fiscal year.
Conclusion: We initiated surveillance of AMU in Calgary NICUs over a three-year period. AMU dropped over the 2012 to 2014 fiscal years at two sites. Identification of baseline levels and pre-existing trends in AMU will have implications for ongoing measurement as AS activities are implemented. The Level 3 NICUs had a higher proportion of patients on three or more antimicrobial agents in keeping with the higher acuity and complexity of patients admitted to these units.
N. Rajapakse, None
D. Dersch-Mills, None