Effects of low dose dexmedetomidine infusion on haemodynamic stress response, sedation and post-operative analgesia requirement in patients undergoing laparoscopic cholecystectomy

Abstract

Background and aim: Dexmedetomidine is a α2 agonist with sedative, sympatholytic and analgesic properties and hence, it can be a very useful adjuvant in anaesthesia as stress response buster, sedative and analgesic. We aimed primarily to evaluate the effects of low dose dexmedetomidine infusion on haemodynamic response to critical incidences such as laryngoscopy, endotracheal intubation, creation of pneumoperitoneum and extubation in patients undergoing laparoscopic cholecystectomy. The secondary aims were to observe the effects on extubation time, sedation levels, post-operative analgesia requirements and occurrence of adverse effects.

Methods: Sixty patients of American Society of Anaesthesiologists(ASA) physical grades I and II undergoing laparoscopic cholecystectomy were randomly allocated into three groups of 20 patients each. Group NS patients received normal saline, Group Dex 0.2 and Group Dex 0.4 patients received dexmedetomidine infusion at 0.2 mcg/kg/h and 0.4 mcg/kg/h respectively, starting 15 min before induction and continued till end of surgery. Parameters noted were pulse rate, mean arterial pressure, oxygen saturation, post-operative sedation and analgesia requirements. SPSS 15.0 version software was used for statistical analysis. ANOVA test for continuous variables, post-hoc test for intergroup comparison, and Chi-square test for discrete values were applied.

Results: In Group NS significant haemodynamic stress response was seen following laryngoscopy, tracheal intubation, creation of pneumoperitoneum and extubation. In dexmedetomidine groups, the haemodynamic response was significantly attenuated. The results, however, were statistically better in Dex 0.4 group compared with Dex 0.2 group. Post-operative 24 hour analgesic requirements were much less in dexmedetomidine groups. No significant side effects were noted.

Conclusion: Low dose dexmedetomidine infusion in the dose of 0.4 mcg/kg/h effectively attenuates haemodynamic stress response during laparoscopic surgery with reduction in post-operative analgesic requirements.

Keywords: Dexmedetomidine; haemodynamic stress response; laparoscopic cholecystectomy.