Effect of MGRNOX-Guided General Anesthesia on Opioid Consumption in Patients

Overview

1. Pain management is a crucial part of general anesthesia surgery. Nociception monitoring can help anesthesiologists better titrate the use of intraoperative analgesic drugs, especially the opioid. 2. Although a variety of nociception monitoring devices have been developed to date, there is not a specific monitoring indicator that serves as the "gold standard" to objectively guide analgesic management in general anesthesia. 3. The MGRNOX index, which is derived from electroencephalogram (EEG), is used to reflect the correlation between noxious stimuli and opioid analgesics in a state of general anesthesia by converting and quantifying the EEG signals collected by the instrument. However, no studies have so far verified the effect of the MGRNOX index-guided analgesic management of general anesthesia on the consumption of opioids in patients. 4. This study aims to explore the effect of MGRNOX index-guided general anesthesia on opioid consumption in patients undergoing laparoscopic cholecystectomy and the primary hypothesis of our study is that using the MGRNOX index to guide intraoperative pain management during general anesthesia can significantly reduce the consumption of remifentanil during the surgery.

Pain management is a critical component of perioperative anesthesia. Traditionally, anesthesiologists adjust analgesic dosages based on intraoperative heart rate or blood pressure, relying heavily on personal clinical experience. This approach often leads to over- or under-administration of analgesics. Currently, opioids remain the primary analgesics used in general anesthesia. Excessive opioid doses can result in postoperative hyperalgesia, delayed recovery, respiratory and circulatory depression, and increased hepatic/renal burden. Conversely, insufficient opioid doses may lead to inadequate analgesia, intraoperative hemodynamic instability, postoperative pain, and agitation. In recent years, various nociception monitoring devices (e.g., SPI, ANI, qNOX) have been developed to quantify intraoperative nociception, assisting anesthesiologists in optimizing analgesic administration to achieve precision and balanced anesthesia. Studies suggest that nociception-guided analgesia during general anesthesia surgery reduces opioid consumption, alleviates postoperative pain, and improves hemodynamic stability compared to traditional standardized management. However, due to the limitations of existing indices, no specific parameter has yet been established as a gold standard for objectively reflecting intraoperative nociception levels. The MGRNOX index, a China-developed metric based on central nervous system monitoring, derives from processed and quantified electroencephalographic (EEG) signals under general anesthesia to reflect a patient's analgesic state. As clinical evidence for MGRNOX remains limited and its impact on intraoperative opioid usage remains unvalidated, the investigators designed this randomized controlled trial to investigate whether MGRNOX-guided general anesthesia reduces opioid consumption during laparoscopic cholecystectomies. Our primary hypothesis is that intraoperative MGRNOX-guided analgesia will significantly decrease remifentanil requirements.