Suppression of perioperative stress response in elective abdominal surgery: A randomized comparison between dexmedetomidine and epidural block.

BACKGROUND AND AIMS: Stress response after surgery induces local and systemic inflammation which may be detrimental if it goes unchecked. Blockade of afferent neurons or inhibition of hypothalamic function may mitigate the stress response.

MATERIAL AND METHODS: A total of 50 consenting adult ASA I/II patients undergoing elective abdominal surgery were randomized to receive either dexmedetomidine ( Group D ) or epidural bupivacaine ( Group E ) in addition to balanced general anesthesia. Laparoscopic surgery, contraindications to epidural administration, history of psychiatric disorders, obesity (BMI >30 kg/m2 ), on beta blockers or continuous steroid therapy for >5 days over last 1 year, and known case of endocrine abnormalities or malignancy were excluded. Serum cortisol, blood glucose, and blood urea were estimated. Hemodynamic parameters, total dose of dexmedetomidine, bupivacaine, emergence characteristics, and analgesic consumption over 24 h postoperatively were recorded. Statistical comparisons were done using Student's t-test, repeated measure analysis of variance followed by Dunnett's test, generalized linear model and Chi-square/Fisher's exact test. A P value <0.05 was considered significant.

RESULTS: Serum cortisol levels were significantly lower in group E than group D 24 h after surgery ( P = 0.029). Intraoperative and postoperative glucose level was lower in group E compared with group D. Time to request of first rescue analgesic was longer in group E than group D ( P = 0.040). There was no significant difference between the number of doses of paracetamol required in the postoperative period ( P = 0.198).

CONCLUSION: Epidural bupivacaine was more effective than intravenous dexmedetomidine for suppression of neuroendocrine and metabolic response to surgery. Dexmedetomidine provided better hemodynamic stability at the time of noxious stimuli and postoperatively.