Oxygen Toxicity in the Resuscitation in Extremely Premature Infants (OXTOX)

Achievement of a Targeted Saturation in Extremely Low Gestational Age Neonates Resuscitated With Low or High Oxygen Concentration: A Prospective Randomized Trial

The investigators hypothesize that using low oxygen concentrations during resuscitation of extremely premature infants will avoid oxidative stress derived damage and improve outcome.

This is a prospective randomized trial enrolling premature infants of less than 28 weeks gestation. Patients are randomly assigned to become resuscitation with an initial oxygen inspiratory fraction (FiO2) of 30% or 90%. Main objective is to reach a target saturation of 85% at 15 min of life. Immediately after birth pre-and-postductal pulse oximeters are set and oxygen saturation (SpO2) continuously monitored and registered as long as the patient requires oxygen supplementation. FiO2 is stepwise adjusted (increased or decreased 10%) every 90 sec according to heart rate, SpO2 and responsiveness. Blood samples are drawn from umbilical cord and at day 1, 2 and 7 from peripheral vein to determine oxidative stress markers (GSH, GSSG), angiogenic factors (VEGF, VEGF receptors, Angiopoietin), pro-inflammatory markers (IL8, TNF alfa) and pro-apoptotic markers (Fas Ligand; Cytochrome C). Urine is collected every day during the first week of life to determine oxidative stress markers (8-oxo-dG; O-tyrosine; F2 isoprostanes; Isofurans). Babies are followed in the NICU and clinical condition recorded. Serial examinations for ROP and Auditory evoked potentials will be performed. Neurodevelopmental outcome is evaluated at 2 years of postnatal life. Main outcome: Achievement of a target saturation of 85% at 15 min of life. Secondary outcomes: acute complications during delivery; chronic complications (BPD, ROP, IPVH); mortality in the neonatal period.

Use of inspiratory fraction of oxygen needed to achieve oxygen saturation in the preset limits 85-88%

Inclusion Criteria: Prematurity of less than 28 weeks gestation Exclusion Criteria: Severe malformations Chromosomopathies Informed consent not signed

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