PVB vs PECS Block in Breast Surgery

Purpose to compare paravertebral thoracic block (PVB) and pectorals nerves block as analgesic option for major breast surgery. 102 patients undergoing reconstruction breast surgery will be randomized into two groups: Group PVB (n=51) will receive US guided paravertebral thoracic block (between T2-T6) performed with 30ml of 0.25% levobupivacaine before general anesthesia (TCI-TIVA) induction. Morphine patient control analgesia (PCA) with loading dose i.v. titrated by the PACU nurse if pain \> 5/10 at rest Group PECS (n=51) will receive US guided pectorals nerves block performed with 30ml of 0.25% levobupivacaine before general anesthesia (TCI-TIVA) induction. Morphine PCA with loading dose i.v. titrated by the post-anesthesia care unit (PACU) nurse if pain \> 5/10 at rest Primary Outcome Measures: Morphine consumption (mg) (Time Frame: 24 hours) in two Groups Secondary Outcome Measures: Pain at rest and during movement quantified as Numerical Rating Scores (0-10) during the first 24 hours postoperatively. Eventual side effects such as nausea/vomiting. Time necessary to perform the procedure. Pain during procedure execution quantified as Numerical Rating Scores (0-10) Hypnotic and opioids intraoperative consumption to ensure general anesthesia with Bispectral Index between 40 and 60.