Main study parameters/endpoints: Primary outcome is the appropriate dose of propofol in 8 different age groups. Optimized propofol doses need to be related with adequate sedation, good quality of intubation conditions and no short term side effects. Secondary endpoints include further evaluation of cerebral perfusion, stress levels and short and long term outcome of the included patients. The incorporation of PK data and genotype of patients is used to make a prediction model for future patients that includes various important cofactors, related to effects and side effects of propofol. Physiological and behavioural responses of the newborns are further explored to find the most reliable and validate neonatal sedation score for intubations.