Nociception refers to the unconscious detection of a noxious stimulus caused by trauma or surgical intervention, which is manifested through responses of the autonomic nervous system. Providing anti-nociception is one of the primary functions of general anaesthesia during surgical procedure.

Opioid-Free Anaesthesia (OFA) is a developing technique and a growing focus in recent research, founded on the concept that eliminating intraoperative opioid use may lead to improved postoperative outcomes.  

Opioid-free anaesthesia refers to the complete avoidance of opioids during the preoperative, intraoperative, and recovery phases. Despite their continued role as a key component in general anaesthesia for managing pain during and after surgery, opioids are linked to a range of side effects including drowsiness, dizziness, constipation, nausea, vomiting, respiratory depression, pruritus, and urinary retention. Additionally, two significant concerns associated with opioid use are the development of hyperalgesia and opioid tolerance. 

Therefore, it is important to investigate and assess novel non-opioid analgesic agents following laparoscopic cholecystectomy as part of strategies aimed at reducing opioid use. Dexmedetomidine, a centrally acting alpha-2 adrenoreceptor agonist, shows considerable promise in enhancing analgesia and stabilizing hemodynamic responses during endotracheal intubation and the creation of pneumoperitoneum. Its perioperative analgesic effectiveness and sedative qualities have been extensively explored across various major surgical procedures, yielding encouraging outcomes. Dexmedetomidine’s potential role in facilitating early recovery following day care surgeries has recently become a topic of growing interest among anesthesiologists. Ketamine possesses strong analgesic, amnesic, and opioid-sparing characteristics. When administered in low doses (less than 0.5 mg/kg), it provides effective analgesia with minimal adverse effects. A single administration of ketamine can markedly decrease postoperative opioid requirements in day care procedures like laparoscopic cholecystectomy.  

The Surgical Pleth Index (SPI) serves as an objective measure to assess the balance between nociception and anti-nociception, helping to guide intraoperative analgesic administration. SPI values range from 0 to 100, with a recommended target range of 20 to 50 during general anesthesia. An SPI value exceeding 50 for more than 3 to 5 minutes typically indicates excessive noxious stimulation, suggesting the need for additional analgesic intervention.  

Entropy monitoring is an objective method consisting of two components—Response Entropy (RE) and State Entropy (SE)—which reflect the levels of analgesia and hypnosis during general anesthesia.  

Ketorolac is a nonsteroidal anti-inflammatory drug that possesses significant analgesic potency. It provides analgesia equivalent to commonly used doses of meperidine and morphine. It has been used extensively in emergency departments for a variety of painful conditions, frequently as a first-line drug.