Reduced antibiotic use in extremely preterm infants with an antimicrobial stewardship intervention

Excessive administration of antibiotics to preterm infants is associated with increased rates of complications. The purpose of the study was to evaluate the effect of an antimicrobial stewardship intervention on antibiotic use in extremely preterm infants.

A before and after study of infants born at ≤28 weeks' gestational age was performed in the neonatal intensive care unit of Queen Silvia's Children's Hospital, Gothenburg, Sweden. Retrospective analysis of the baseline period (January-December 2014) guided the development of a limited antimicrobial stewardship intervention. The intervention consisted of updated local guidelines with a focus on shortened and standardised treatment duration plus increased access to infectious disease consultant advice. It was fully implemented during the intervention period (October 2017-September 2018).

Primary aim was to compare antibiotic use, defined as antibiotic treatment days per 1000 patient-days, between the two periods, and the secondary aim was to evaluate the number of days with meropenem-based regimens before and after the intervention.

We included 145 infants with a median birth weight of 870 g and median gestational age of 26 weeks. The baseline period comprised 82 infants and 3478 patient-days, the intervention period comprised 63 infants and 2753 patient-days. Overall antibiotic use (treatment and prophylaxis) was 534 versus 466 days per 1000 patient-days during the baseline and intervention periods, respectively. Antibiotic treatment days decreased from 287 to 197 days per 1000 patient-days. The proportion of meropenem-based regimens was 69% versus 44%, respectively. No increases in mortality or reinitiation of antibiotics were seen.

Implementation of a limited antimicrobial stewardship intervention anchored in analysis of previous prescription patterns can contribute to safe decreases in antibiotic use in extremely preterm infants.