Inclusion Criteria:  Aged 18 years or older Patients scheduled for coronary artery bypass graft surgery (CABG), which includes a complete midline sternotomy.  Exclusion Criteria:  CABG surgery which did not include a complete midline sternotomy Valve surgery Aortic surgery Emergency cardiac surgery Known allergy for ropivacaine Participation in another clinical trial Known drug abuse Preoperative cognitive dysfunction Preoperative pain therapy with opioids or anticonvulsants 14 days before surgery Patients unable to use Patient Controlled Analgesia (PCA) Need of reintubation after initial extubation