CRP and depressive symptom measurement: The secondary outcomes included pain NRS scores for moving incision, visceral, and rest incision pain at 0–6 h, 6–12 h and 12–24 h; pressure pain threshold and tolerance at 30 min and 24 h postoperatively; PCIA drug consumption, number of compressions, and dosage of rescue analgesics; time to first PCIA compression; serum C-reactive protein (CRP) at 24 h; incidence of drug-related side effects; and rates of anxiety, depression, and sleep disorders on postoperative day 2.