Dexmedetomidine Reduces Sevoflurane MAC-BAR During Pneumoperitoneum
Trial Parameters
Brief Summary
This clinical trial aims to learn the impact of dexmedetomidine on the minimum alveolar concentration blunting the adrenergic response (MAC-BAR) of sevoflurane to carbon dioxide pneumoperitoneum in patients undergoing laparoscopic cholecystectomy. It will also learn about the effect of dexmedetomidine on hemodynamic parameters. The main questions are: * Does dexmedetomidine reduce the MAC-BAR of sevoflurane required to suppress the sympathetic response to carbon dioxide pneumoperitoneum? * Would dexmedetomidine administration dose-dependently reduce the minimum alveolar concentration blunting the adrenergic response of sevoflurane required to suppress the sympathetic response to carbon dioxide pneumoperitoneum? Researchers will compare low-dose dexmedetomidine to high-dose dexmedetomidine to see if dexmedetomidine works to treat postoperative negative behavior change and emergence delirium. Participants will: * Take intravenous dexmedetomidine or 0.9% saline (a look-alike substance that contains no drug) * Study drug infusions were initiated 15 minutes prior to anesthesia induction, allowing a minimum of 30 minutes to elapse before surgical incision to achieve steady-state plasma and brain concentrations.
Eligibility Criteria
Inclusion Criteria: * 1\. Aged 18-45 years. * 2\. American Society of Anesthesiologists (ASA) grade I - II. * 3\. Patients undergoing elective laparoscopic cholecystectomy. Exclusion Criteria: * 1\. Inability to provide informed consent; * 2\. History of chronic pain or substance abuse; * 3\. Pregnancy; * 4\. Body mass index (BMI) ≥ 30 kg/m2; * 5\. Known allergies to the study medications; * 6\. Intake of medications within the last 72 hours that potential interfere with the determination of the MAC-BAR; * 7\. Any other condition deemed exclusionary by the investigators.