Early-onset Sepsis

A previous pharmacy residency project was done 20 years ago looking at the best dosing for the antibiotic gentamicin for babies up to 7 days old. This study showed that giving the dose less often leads to better drug concentrations than giving the dose more often. Our gentamicin dosing at the Children's Hospital at London Health Sciences Centre is based on the better dosing from the study. This dosing is gentamicin 3 mg/kg every 24 hours for babies less than 35 weeks gestational age and 3.5 mg/kg every 24 hours for babies at least 35 weeks gestational age. These results were never published. Different dosing is used at different hospitals. It is important that we check that our gentamicin dosing is still reaching safe and effective drug concentrations in the current study. The study will look at the gentamicin drug concentrations of babies up to 7 days old, including premature and term babies. We will also confirm if the babies have kidney or hearing damage from gentamicin. We will compare the gentamicin drug concentrations from this study to the past data to see if the dosing is still the best. The results can help form a guideline for the Children's Hospital and surrounding hospitals.

The goal of this clinical trial is to learn if preterm infants who are prescribed antibiotics shortly after birth can safety receive a shorter course of antibiotics (24 to 36 hours instead of 48 hours). The main questions it aims to answer are: * Does short-course ampicillin provide high enough levels of ampicillin at 48 hours? * Is short-course ampicillin safe for preterm infants to receive? Preterm infants who are being prescribed ampicillin by their doctor and enroll in the study will stop ampicillin after a shorter than typical course, and researchers will collect blood samples to measure their ampicillin levels and follow them clinically to see how they do after receiving short-course ampicillin. Participants will: * stop ampicillin earlier than 48 hours (between 24 to 36 hours, depending on how premature they are and the dosing of ampicillin their doctor has prescribed) * have a blood sample collected around 48 hours from when they started ampicillin * have their data collected until 30 days after they receive short-course ampicillin, or until hospital discharge, whichever is sooner

In this study, three neonatal evidence-based antibiotic stewardship strategies will be implemented in Dutch hospitals. These include the early-onset sepsis (EOS) calculator, procalcitonin (PCT)-guided therapy, and IV-to-oral switch therapy. These strategies have been proven to be effective and safe and are already applied in several Dutch hospitals. However, this is not the case for all hospitals, leading to significant variations in clinical practice. To facilitate the translation of evidence into practice, active implementation will take place. The primary research design is a prospective implementation study, using a multicenter, non-randomized pre-post design. The aim is to assess the impact of implementing a bundle of antibiotic stewardship interventions (including the EOS calculator, PCT-guided therapy and iv-to-oral switch therapy) in Dutch hospitals, using a multicomponent implementation strategy, on both clinical and implementation outcomes, with a particular focus on evaluating the employed implementation strategies. A combination of qualitative and quantitative research methods will be used to assess outcomes. Quantitative clinical data from neonates in the pre- and post-implementation periods will be retrospectively collected by the Business Intelligence units of participating hospitals and anonymized before being provided to the central research team. Qualitative data will be gathered through focus groups, interviews, and surveys.