Intra-articular Adjuvant Analgesics Following Knee Arthroscopy: Comparison between Dexmedetomidine and Fentanyl

-----------------------------------------------------------------------------------------------------Abstract: This study was designed to compare the analgesic effect produced by intraarticular (IA) administration of either dexmedetomidine or fentanyl in combination with bupivacaine following arthroscopic knee surgery. Ninety ASA physical status I–II patients, scheduled for knee arthroscopic procedures were randomly assigned into three groups. The control group B received 30 ml 0.25% bupivacaine only; group B/D received 30 ml 0.25% bupivacaine and dexmedetomidine 1μg/kg, and group B/F received30 ml 0.25% bupivacaine and fentanyl 1μg/kg at the end of arthroscopy. Postoperatively, pain visual analogue scale (VAS) at rest and during movement, the time to first postoperative analgesic request, and the total postoperative analgesic use during the first 24 h were recorded. The time to first postoperative analgesic request was longer in the B/D group (450 ±85 min) and B/F group (465 ± 90 min) versus control B group (230 ±85 min) (P < 0.05). Supplementary analgesic consumption during the first 24 h was almost equivalent for the B/D and B/F groups (mean meperidine consumption of 35.0 ± 11 and 33.5± 15 mg respectively), while consumption was greater in the control B group (75.7 ± 14 mg) (P<0.05). No early side-effects were noted. It was concluded that, both dexmedetomidine, and fentanyl, provide a comparable analgesia after arthroscopic knee surgery when administered intraarticularly in combination with bupivacaine.