Preterm Neonates

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

This is a prospective, single-center Phase II observational study investigating the predictive value of the "Peripheral(-muscle) Oxygenation and Perfusion Score" (POP-Score), a novel non-invasive composite index, for early detection of infection/inflammation in neonates. The POP-Score combines peripheral muscle oxygenation measured via near-infrared spectroscopy (NIRS) with routinely monitored clinical parameters (heart rate, oxygen saturation, systolic blood pressure, and subcutaneous fat thickness). The study aims to determine the optimal cut-off value of the POP-Score measured within the first 6 hours after birth to predict elevated C-reactive protein (CRP ≥20 mg/L) within 48 hours. Additionally, multi-site NIRS measurements (cerebral, peripheral muscle, intestinal, and flank) will be evaluated to assess their association with inflammation. The study includes term and moderate-to-late preterm neonates (birth weight ≥2000g) with respiratory distress, admitted to the neonatal intensive care unit at the Medical University of Graz.

Preterm neonates younger than 37 weeks gestational age receiving caffeine therapy for apnea of prematurity in a NICU setting.

This work aims to investigate and compare the levels of serum endocan and serum copeptin on the first day of life and correlate their levels to the severity of respiratory distress in preterm neonates suffering from respiratory distress syndrome.