Dexmedetomidine and Fentanyl as Adjuvant to Bupivacaine for Epidural Analgesia in Gastrectomy Surgery

Abstract

Background: Opioids as epidural adjunct to local anaesthetics have been in use so long and the synergism between epidural local anaesthetic agents and opioids are well established. Dexmedetomidine (α-2 agonist) is being increasingly used for similar purpose but evidence for the combination of local anaesthetic agents with dexmedetomidine in epidural analgesia is limited. Gastic cancer is increasing day by day in our country and removal of tumor by gastrectomy surgery is choice of treatment. The present study was conducted to compare the analgesic, hemodynamic, sedative effects of epidurally administered dexmedetomidine and fentanyl when combined with bupivacaine in a patient undergoing gastrectomy surgery along with general anaesthesia.
Methods: This randomized controlled trial study was carried out in the Department of Anaesthesia, Analgesia and Intensive Care Medicine, BSMMU, Dhaka. The study was been conducted 12 month after obtaining approval from the institutional Review Board and informed written consent from the patient. About 40 patients aged between 40 and 70 years, posted for gastrectomy surgery were included in this study. The patients were randomly allocated into two equal groups. Group A received general anaesthesia along with epidural fentanyl and bupivacaine. Group B received general anaesthesia along with epidural dexmedetomidine and
bupivacaine. During surgery, hemodynamic status of the patients had been carefully recorded. Following surgery, pain intensity was recorded using a visual analog scale (VAS) for 6 hours and observed for the time of first rescue analgesic requirement, post-operative sedation score by Ramsay sedation score, and surgeons satisfaction by likert scale. A statistical analysis was carried
out by using the Statistical Package for Social Sciences version 23.0 for Windows. Chi-Square test used to analyze the categorical variables and student t-test used for continuous variables. P value <0.05 was considered as statistically significant.
Results: Age, height, and weight were almost identical between two groups. Duration of surgery and anaesthesia were almost similar between two groups. Systolic blood pressures, diastolic blood pressure, MAP were almost similar between two groups and were statically not significant (p>0.05). Mean heart rate of group B was significantly lower (p<0.05) than that of group A. Post-operative visual analog scale was reduced significantly (p<0.05) in group B than group A. The time of first analgesic requirement was significantly higher (p<0.05) in group B. The mean sedation score was also significantly higher (p < 0.05) in group B than group A.
Conclusion: Dexmedetomidine seems to be a better alternative to fentanyl as an epidural adjuvant to local anaesthetics as it decreases pain intensity during post-operative period, delayed time of first analgesic supplementation, provides better sedation level without harmful derangement on hemodynamics.