Feasibility study of bilateral thoracic paravertebral block for postoperative analgesia in patients after off-pump coronary artery bypass grafting

Objective To investigate the feasibility of bilateral thoracic paravertebral block for postoperative analgesia in patients after off-pump coronary artery bypass grafting(OPCABG).Methods Upon the approval of institutional Ethics Committee and informed consent,forty patients ASAⅡorⅢaged 52-77 yr with BMI(body mass index)【