4CPS-241 Impact of antibiotic prescribing in an emergency department on hospital stays, readmission and mortality

Abstract

university hospital. Patients 0-35 days old treated with gentamicin and with plasma concentrations (Cp) were reviewed. The descriptive analysis was performed with the SPSSV.24 programme. Results 47 patients with a median age of 3 days (0-33) were studied, 33 male. 26 (55.3%) were <1 week old. 34 (72.3%) were admitted for neonatal sepsis and 7 (14.9%) for urinary infection. Gentamicin was used in combination with ampicillin in 45 cases (95.7%) and empirically in 34 (72.3%). The initially prescribed dose was 4 mg/kg/day in 36 (77%) and 5 mg/kg/day in 8 (17%), with no differences in weeks of life. Cp were extracted with a median of 2 days (1-4) after the start, the median peak was 7.5 mg/L (3.5-21.6) and 29 (62%) had a peak <8 mg/L. The trough was <0.2 mg/L in 26 patients and of those that were quantified, the median was 0.4 mg/L (0.2-1.3), and was higher than 1 mg/L in only one case. It was recommended to increase the dose in 26 (55.3%) and reduce it in 4 (8.5%) patients, with 90% acceptance. A second Cp determination was requested in 16 (34%) cases with a median peak of 9 mg/L (6-12) and trough levels always <0.5 mg/L. It was recommended to increase the dose in 5 cases with an acceptance of 94%. Conclusion and relevance The dose prescribed was lower than recommended in neonates >1 week old. Cp allowed detection and correction of deviations from the recommended peak or trough levels in 64% of cases, mainly due to low peak levels, with high acceptance of TDM. Plasma determination and TDM of gentamicin continues to be an essential tool to achieve the recommended PK/PD profile.