Patients received 10 mL of 0.75 % ropivacaine along the skin incision before skin closure , followed by wound infusion 2 mL/hour of 0.375 % ropivacaine or epidurally 10 mL of 0.75 % ropivacaine in the beginning of surgery followed by 10 mL of 0.2 % ropivacaine 6 hourly .