Very low birth weight infants has increased dramatically their survival. Survival without neurologic disturbance varies a lot between centers.There is evidence that fluctuations in cerebral blood flow influences the appearance of intraventricular hemorrhage and itself implies a detrimental neurologic developing.The electroencephalography is the result of electric base membrane activity on rest, and it's influenced by the blood flow either. The Amplitude-integrated electroencephalography is a novel tool, that is capable to be continuously used at the patient bed and is easily to be read by the trained clinician.The hypothesis is that common procedures as Surfactant instilation, Indomethacin and Aminophyline infusion as the appearance of apneas alters the aEEG register. It is a prospective study that tries to recruit 10 < 30 weeks of gestational age with aprofen consent to monitorize the aEEG since birth to the seventh day of live.