Utilization of NIRS Monitor to Compare Regional Cerebral Oxygen Saturation Between Opioid and Opioid-Sparing Anesthesia and Post-Operative Cognitive Dysfunction in Elderly Patients Undergoing Laparoscopic Surgery: A Double-Blinded Randomized Controlled Trial

Laparoscopic surgeries in elderly patients are becoming increasingly common due to their minimally invasive nature and faster recovery times [1]. However, these procedures often involve prolonged operative durations and the use of opioids for pain management. While opioids provide effective analgesia, their systemic effects, such as reduced cerebral blood flow, may contribute to cerebral hypoperfusion, potentially leading to post-operative cognitive dysfunction (POCD) [2]. Elderly patients undergoing laparoscopic surgeries are at increased risk of POCD, which can impair recovery and quality of life [3]. Opioids, commonly used for intraoperative analgesia, may exacerbate this issue by causing cerebral hypoperfusion [4]. Despite advances in anesthesia protocols, there is limited evidence on the direct association between opioid use, cerebral perfusion (measured by NIRS), and cognitive outcomes. Near-infrared spectroscopy (NIRS) is a non-invasive technique that allows real-time monitoring of cerebral oxygen saturation [5]. It can detect changes in frontal lobe perfusion, offering a valuable tool for understanding how anesthesia impacts cerebral blood flow and cognitive outcomes. Opioid-sparing anesthesia regimens, such as those using dexmedetomidine, have shown promise in minimizing the risk of cognitive decline, but their effect on cerebral oxygenation remains underexplored [6]. This double-blind randomized controlled trial will recruit 100 patients. During anesthesia, the participants will be divided into two groups: Group A (50 patients: opioid-based anesthesia using propofol + fentanyl) and Group B (50 patients: non-opioid-based anesthesia using propofol + ketamine). NIRS technology will then be used to monitor regional cerebral oxygen saturation in real time. Before and after the surgery, patients will be asked questions to check for cognitive dysfunction. For example, patients may be asked to name the colours written in text, connect a set of dots as quickly as possible to assess visual attention and executive function, and perform a task where they trace a path from a start point to an endpoint through a complex network within 15–60 minutes. Orientation will also be assessed by asking patients for the date, year, day, place, and city. Additionally, short-term memory will be tested by having patients read five words and repeat them after completing other tasks. Three pictures of animals will be shown, and patients will be asked to name each one. The study aims to optimize anesthesia practices, reduce cognitive complications, and improve recovery outcomes in elderly patients.

References:

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