Effect of Using Dexmedetomidine with Ultrasound Guided Transversus Abdominis Plane Block on Postoperative Stress Response in Abdominal and Pelvic Surgeries: Comparative Study

Abstract
Background: Perioperative pain and stress of surgery induces changes in hormonal secretion. Tissue trauma that occurs as a result of surgical interventions is associated with both metabolic and endocrine responses. The present study was performed in abdominal and pelvic cancer surgeries, to compare the effect of bupivacaine versus bupivacaine with dexmedetomidine in ultrasound guided Transversus Abdominis Plane (TAP) block on post-operative heamodynamics and attenuation of endocrine response during surgery.
Patients and Methods: The study included seventy five patients who were randomly allocated into three groups: Bilateral ultrasound guided TAP block was done to all patients before recovery where group TAP (n=25) received bupivacaine (0.25%), group TAP + Dex (n=25) received dexmedetomidine with the bupivacaine and group TAP + IV-Dex (n=25) received bupivacaine in addition to intravenous dexmedetomidine. Blood samples were withdrawn before the block and at 8 hours and 24 hours post-operative.
Results: Heamodynamics did not show clinically signif-icant difference in the three groups where only 3 patients had bradycardia that was treated with atropine. Serum cortisol and glucose levels were comparable in all study groups. Cortisol level was within normal range and showed decline at 8 and 24 hours postoperative which indicates attenuation of the surgical stress response.
Conclusion: The use of dexmedetomidine with TAP block blunted the stress response to surgery without affecting heamodynamics.