High dose dexamethasone offers better postoperative analgesia than dexmedetomidine when added to intra articular ropivacaine following knee arthroscopic surgery

Objective: Adequate pain relief after knee arthroscopy reduces surgical stress response and postoperative morbidity and improves recovery and rehabilitation. The objective of our study was to compare the duration of postoperative analgesia produced by high dose with that of low dose dexamethasone when added to dexmedetomidine and ropivacaine for intra-articular injection following knee arthroscopy. Methodology: Prospective multicenter double blind study of 60 patients undergoing arthroscopic knee surgery from January 2015 to May 2015, randomly assigned into 3 groups; Group I (20 ml 0.2% ropivacaine), Group II (16 ml of 0.2% ropivacaine + dexmedetomidine- 1 µg/kg diluted to 4 ml) and Group III (dexamethasone 300 µg/kg diluted with  0.2% ropivacaine upto 20 ml). The duration of analgesia (VAS Score less than 4) and time to first postoperative analgesic request, total analgesic used during first 24 hours were recorded. Clinical incidences of nausea, vomiting, bradycardia, hypotension or other side-effects requiring intervention were observed in all the groups. The numerical data were expressed as mean ± standard deviation (SD). Student’s t-test was employed to calculate the statistical differences in continuous variables between the groups, categorical variables were compared with chi-square test or Fisher’s exact test as applicable. A P < 0.05 was considered to be statistically significant.