Does ESP Block Reduce Pain and Opiates Consumption After Surgery

patients will be divided randomly into two groups before the beginning of operation: Group 1: patients will be treated to standard pain control treatment ; Group 2: patients will receive Erector spinea block (30-40 mL Ropivacaine 0.375% plus 2 mg Dexamethasone injection using ultrasound approach) additionally to standard pain control treatment The ESB (erector spinae plane block) will be performed at the beginning of the procedure while the patient under general anesthesia, in assistance of ultrasound for visualization, anesthetic injection 30-40 mL Ropivacaine 0.375% plus 2 mg Dexamethasone administered on each side between thoracic transversus process and longitudinal spinea muscle. in the the postoperative care room, the vital sings and pain level will be continuously monitored. During the postoperative period stay the pain level of each patient will be assessed by of Visual Analog Score of pain (VAS: 0-10) interviewing the patient every 30 minutes from the patient's admission from operation room and thereafter every 1 - 4 -8 -12 -24 -48 - 72 hours, at discharge, 7- 14-21 days. For a more accurate assessment of pain, a pre-operative baseline level of pain eill be recorded. Any postoperative pain will be routinely managed by 5-10 mg of intravenous morphine to achieve a VAS scale of none or mild pain (1-5). investigators will also continue to record events of postoperative nausea and vomiting (PONV) within 24 hours after procedure. The PONV will be assessed by the PONV Impact Scale score, based on numerical responses to questions. A PONV Impact Scale score of ≥5 defines clinically relevant PONV. Recording of urinary retention, constipation, opioid requirements and itching will also be preformed. After 3 and 6 months a telephone survey will be preformed - recording pain related to surgery and to asses chronic pain syndrome. During the phone conversation, patients will be asked to answer by the brief pain inventory.