Double-blind Study to Assess effectIveness of Pectoral Nerves Block After Breast Surgery on Piritramide Consumption

Inclusion Criteria: 1. Age ≥18 years old 2. Female 3. Subjects undergoing either a conservative or non-conservative breast surgery associated with axillary dissection 4. ASA score ≤ 3 5. Completion of all necessary screening procedures within 30 days prior to randomisation 6. Adequate Renal Function including: Serum creatinine ≤ 1.5 x upper limit of normal (ULN) or estimated creatinine clearance ≥ 60 ml/min as calculated using the method standard for the institution 7. Adequate Liver Function, including all of the following parameters: 1. Aspartate and Alanine Aminotransferase (AST and ALT) ≤ 1.5 x ULN If Aspartate and Alanine aminotransferase (AST and ALT) are \> 1.5 x ULN, total serum bilirubin should be assessed and must be ≤ 1.5 x ULN unless the patient has documented Gilbert Syndrome 2. Alkaline phosphatase ≤ 2.5 x ULN 8. Signed informed consent 9. Willingness and ability to comply with the study scheduled visits, treatment plans, laboratory tests and other procedures Exclusion criteria: 1. Any illness or medical condition that is unstable or could jeopardize the safety of the patient or her compliance with study requirements 2. Allergy to local anaesthetics 3. Known allergy or hypersensitivity to Paracetamol, Diclofenac, Piritramide or excipients 4. Coagulopathy or taking oral anticoagulant/ antiaggregant within 7 days prior to surgery 5. BMI\> 35 kg / m2 6. Infection near the puncture site 7. Inability to understand the pain assessment scales (VAS and McGill questionnaire) 8. Severe hepatic impairment: elevated transaminases with factor V ≤ 50% 9. Severe heart failure: NYHA classification III or IV and/or LVEF \< 50% 10. Pregnant or lactating women 11. Concurrent treatment with daily basis chronic opiate type painkillers not ended 1 month prior surgery 12. Scheduled breast reconstruction at the time of surgery 13. Metastatic subjects 14. Subjects with breast implants 15. Patients that require bilateral mastectomy or bilateral lumpectomy