The purpose of this study is to examine the effects of Dobutamine as compared to Dopamine in term and preterm neonates with arterial hypotension on cerebral and renal oxygenation, fractional tissue oxygen extraction, mean arterial blood pressure and cardiac output.

The investigators hypothesize that Dopamine has a stronger effect on blood pressure than Dobutamine but Dobutamine has a stronger effect on cerebral oxygenation and cardiac output than Dopamine.

Inclusion Criteria:

• fluid refractory arterial hypotension
• newborn infant below 44 weeks postmenstrual age
• parental informed consent

Exclusion Criteria:

• preterm infant below 28 weeks postmenstrual age during the first week of life
• congenital life-threatening malformations
• decision for palliative care
• hemorrhagic shock
• other obvious cause for arterial hypotension that requires immediate specific treatment, e.g. tension pneumothorax