Introduction
postoperative pain, low infection, visceral pain, blood loss, pain, gallbladder disease, trauma
BLOOD LOSS, GALLBLADDER DISEASE
Laparoscopic cholecystectomy (LC) has been the gold standard for surgical treatment of gallbladder disease because of short surgery time, good surgical vision, less trauma, less blood loss, easy recovery, and low infection rate [Ketamine, a noncompetitive, channel-blocking NMDA-R antagonist, is considered to be highly correlated with acute early postoperative pain (incisional pain, visceral pain, and OIH). The studies indicated that preemptive ketamine might reduce acute early postoperative pain, especially incisional pain and visceral pain, in patients undergoing gynecological laparoscopic surgery [In this study, we estimate the safety and efficacy of esketamine for preventing postoperative pain in patients undergoing laparoscopic cholecystectomy, and determine the median effective dose(ED50) and 95% effective dose (ED95) of esketamine by applying the up-and-down sequential allocation technology designed by Dixon and Massey.