Sixty-six patients with gastric carcinoma scheduled for gastrectomy were randomly divided into 3 groups , namely group P ( n = 22 ) , group E ( n = 22 ) and group V ( n = 22 ) , to receive preemptive epidural analgesia combined with postoperative epidural analgesia , exclusive postoperative epidural analgesia , and exclusive postoperative intravenous analgesia , respectively .
