PROSPECTIVE STUDY TO COMPARE EFFECTIVENESS OF ADENOSINE WITH MAGNESIUM SULPHATE AS ADJUVANTS TO ROPIVACAINE IN ULTRASOUND GUIDED TRANSVERSUS ABDOMINIS PLANE BLOCK FOR POSTOPERATIVE ANALGESIA IN PATIENTS UNDERGOING OPEN ABDOMINAL SURGERY

Abstract

: Postoperative pain following abdominal surgeries significantly affects recovery and outcomes. The transversus abdominis plane (TAP) block, a regional anesthesia technique, has gained popularity for its ability to provide effective analgesia and reduce opioid consumption. Aim: To determine the comparative effectiveness of adenosine and magnesium sulphate as adjuvants to ropivacaine in TAP block for post-operative analgesia in patients undergoing abdominal surgeries. Methods: A prospective comparative study included 100 patients undergoing elective abdominal surgeries. Participants were allocated into two groups: one received ropivacaine with MgSO₄ and the other with adenosine in ultrasound-guided TAP blocks. Demographic data, intraoperative and postoperative hemodynamic parameters, pain scores (VAS), sedation levels (Ramsay Sedation Score), rescue analgesic requirements, and complications were recorded. TAP blocks were performed using ultrasound guidance, ensuring precise placement of the local anesthetic and adjuvant. Postoperative pain was assessed at regular intervals up to 24 hours. Statistical analyses were conducted to compare analgesic efficacy, duration, opioid consumption, and safety profiles between the two groups. Results: Demographic characteristics were comparable between groups, with no significant differences. Both groups exhibited stable intraoperative hemodynamic parameters, no intraoperative complications were observed, underscoring the safety of both adjuvants.   Postoperative pain scores were initially similar but diverged significantly at 24 hours.  The MgSO₄ group reported lower VAS scores (3.5 ± 1.3) compared to the adenosine group (4.1 ± 1.3, p = 0.040). MgSO₄ also demonstrated superior analgesic duration,  with a longer time to first rescue analgesia and longer duration of analgesia overall.  Patients in the MgSO₄ group required fewer tramadol boluses, with 62% needing only  one or two doses compared to 70% in the adenosine group requiring two or three  doses (p < 0.001). Sedation levels were comparable, though the MgSO₄ group  exhibited slightly lower scores at one hour postoperatively (p = 0.048). Magnesium  Sulfate (MgSO₄ ) significantly prolonged the duration of analgesia compared to  adenosine, with a mean analgesia duration of 483.4 ± 48.1 minutes versus 415.3 ±  29.8 minutes (p < 0.001), and a mean time to first rescue analgesia does also being  longer than the adenosine group patients (421.5 ± 30.9 minutes vs 372.8 ± 38.2 minutes, p < 0.001).  Complications such as nausea and vomiting were minimal and comparable between groups, with no significant differences. Conclusion:  Both MgSO₄ and adenosine proved to be safe and effective adjuvants in TAP blocks for postoperative pain management. MgSO₄ demonstrated superior analgesic efficacy, prolonged duration, and reduced opioid requirements, making it particularly suitable for surgeries with higher pain profiles or extended recoveries. Adenosine provided adequate short-term analgesia, making it a viable alternative for low-pain or short duration procedures.