Continuous Paravertebral Block on Postoperative Quality of Recovery After Hepatectomy

Moderate to severe postoperative pain often influence patients quality of recovery after hepatectomy. Systemic opioids given with patient-controlled analgesia has been used after hepatectomy in many medical center, but the analgesic effect can be limited and undesirable side effects may bring about negative effects on patients recovery. Regional block has been proved to improve patients postoperative recovery in many kinds of surgeries. The investigators therefore designed a prospective, randomized, subject and assessor blinded, parallel-group, placebo controlled study to test the hypothesis that continuous right thoracic paravertebral block increase patients quality of recovery score on the 7th postoperative day after hepatectomy in patients receiving i.v. patient-controlled analgesia (PCA) with morphine.