Evaluation of Intraoperative Sufentanil Administration on Chronic Postsurgical Pain Incidence in Patients Undergoing Non-Major Scheduled Abdominal Surgery

The primary objective of this study is to evaluate the correlation between the intraoperative administration of **sufentanil** doses and the incidence of chronic postsurgical pain (CPSP) at 3 months in patients undergoing non-major scheduled abdominal surgery. This is clinically relevant as understanding this correlation could inform anesthetic practices and potentially reduce the incidence of CPSP, improving postoperative outcomes and patient quality of life.

Secondary objectives include:

• The intensity of acute postoperative pain at 24 and 48 hours postoperatively.
• The time limit for resorting to level III analgesics within 24 hours post-operatively.
• Consumption of opioid derivatives and opioids at 24 hours, 48 hours, and 3 months after surgery.
• The intensity of pain at 3 months and the incidence of neuropathic pain at 3 months after surgery.

The clinical trial focuses on patients experiencing **chronic postsurgical pain** following non-major scheduled abdominal surgery. The study population includes both male and female participants, aged over 18 years, who have provided written or oral informed consent to participate. The trial does not involve a vulnerable population. The sponsor has not provided information regarding the total number of participants. Participants were selected based on their eligibility for non-major scheduled abdominal surgery, and no specific lifestyle considerations such as diet or physical activity were highlighted. The trial aims to evaluate the correlation between the intraoperative administration of sufentanil doses and the incidence of chronic postsurgical pain at three months post-surgery.

The clinical trial is designed to evaluate the correlation between the intraoperative administration of **sufentanil** and the incidence of chronic postsurgical pain (CPSP) at three months in patients undergoing non-major scheduled abdominal surgery. This study is a randomized, double-blind, controlled trial, ensuring that neither the participants nor the researchers know who is receiving the active treatment or the placebo, thus minimizing bias. The trial is expected to commence on March 17, 2024, and conclude by June 17, 2026, with a total duration of approximately two years and three months.

Participants will undergo a series of study visits, beginning with an inclusion (screening) visit to confirm eligibility based on criteria such as age over 18 years, undergoing non-major scheduled abdominal surgery, and providing informed consent. Following the initial screening, participants will be randomly assigned to receive either the active treatment or a placebo. The primary endpoint is the incidence of CPSP at three months post-surgery, while secondary endpoints include post-operative pain intensity, time to use of third-step analgesics, and consumption of opioid derivatives at various intervals post-surgery.

Follow-up visits will occur at 24 hours, 48 hours, and three months after surgery to assess pain intensity and opioid consumption. The end-of-study visit will take place at the three-month mark to evaluate the primary and secondary endpoints comprehensively. Participant involvement is expected to last for the duration of the study, with conditions for early termination including withdrawal of consent or any adverse events that may compromise participant safety. The trial is categorized as low-intervention, with **sufentanil** being administered via infusion, adhering to its authorized use conditions.

The clinical trial involves the administration of **sufentanil**, a potent opioid analgesic, as the experimental medication. Sufentanil is provided in the form of a **solution for injection** and is administered via **infusion**. The dosing regimen for sufentanil is calculated based on the patient's body weight, with a maximum daily dose of 30 µg/kg and a maximum total dose of 120 µg/kg over the course of the treatment. The treatment period is limited to a maximum of 4 days. The primary objective of the trial is to evaluate the correlation between intraoperative administration of sufentanil and the incidence of chronic postsurgical pain (CPSP) at 3 months in patients undergoing non-major scheduled abdominal surgery. Participant compliance with the dosing schedule will be monitored throughout the trial to ensure adherence to the protocol.

In addition to the experimental treatment, standard-of-care therapies may be administered as deemed necessary by the clinical investigators. These therapies are not specified in the trial documentation and will be determined based on individual patient needs and clinical judgment. No placebo or comparator treatment is explicitly mentioned in the trial protocol. The administration of any non-experimental treatments will be documented and considered in the analysis of the trial outcomes.

The clinical trial aims to assess the efficacy of **Sufentanil** in relation to the incidence of chronic postsurgical pain (CPSP) at 3 months following non-major scheduled abdominal surgery. The primary endpoint for evaluating efficacy is the incidence of CPSP at 3 months post-surgery. Secondary endpoints include post-operative pain intensity measured by the Numeric Rating Scale (NRS) of 11 points at 24 and 48 hours after discharge from the operating room, the time taken until the use of third-step analgesics, and the consumption of opioid derivatives and opioids at 24 hours, 48 hours, and 3 months post-surgery. Additionally, CPSP intensity and neuropathic pain incidence at 3 months will be assessed.

Data collection will involve the use of validated scales such as the NRS for pain intensity assessment. Measurements will be taken at specified timepoints, including 24 hours, 48 hours, and 3 months post-surgery. The analysis will focus on correlating intraoperative **Sufentanil** doses with the incidence and intensity of CPSP, as well as other secondary endpoints. The trial is designed to provide insights into the relationship between **Sufentanil** administration and post-surgical pain outcomes, contributing to the understanding of pain management in non-major abdominal surgeries.