Transversus abdominis plane (TAP) block is often recommended for abdominal surgery. Ropivacaine TAP block and intravenous lidocaine infusion are important components of multimodal analgesia for colorectal surgery. However, both of them are the local anesthetics and the safety of combination is unknown, so investigators design the study to explore the safety of the synergistic application of ropivacaine TAP block and intravenous lidocaine infusion in patients undergoing colorectal surgery.
