Intubation and mechanical ventilation are majors component of intensive care for premature neonates with respiratory distress syndrome (RDS) and is associated with physiologic, biochemical, and clinical responses indicating pain and stress in prematures. Although morphine is one of the most used drugs for premedication and for sedation and analgesia during mechanical ventilation in the treatment of RDS its pharmacological profile precludes several limitations mostly due to its much delayed onset of action what makes the drug not suitable as premedication and due to its prolonged duration of action mainly in prematures. Unlike morphine, remifentanil has an unique pharmacokinetic properties with a rapid onset of action and, a fast decrease in plasma concentration after interruption of administration due to a context-sensitive half-time of 3.2 minutes. So, it could be the ideal opioid for neonates who are especially sensitive to respiratory depression by opioids