Isobaric ropivacaine with or without dexmedetomidine for surgery of neck femur fracture under subarachnoid block.

BACKGROUND AND AIMS: Dexmedetomidine has a promising role as an intrathecal adjuvant. However it's role as an adjuvant to ropivacaine has not been evaluated extensively. This study is designed to find out the effect of addition of dexmedetomidine 5 μ g to isobaric ropivacaine 18.75 mg on block characteristics and hemodynamic parameters in patients undergoing surgeries for fracture neck of femur under subarachnoid block (SAB).

MATERIAL AND METHODS: Sixty-one American Society of Anesthesiologists (ASA) Class I or II patients between 18-60 years undergoing surgeries for fracture neck of femur under SAB were recruited and randomized into two groups. Thirty patients in Group RN received 2.5 ml isobaric ropivacaine 0.75% (18.75 mg) with 0.5 ml normal saline (NS) to make a total volume of 3 ml, while 31 patients in Group RD received 2.5 ml isobaric ropivacaine 0.75% with dexmedetomidine 5 μg diluted with NS to make a total volume of 3 ml. The block characteristics, hemodynamic parameters, and side effects were recorded in both the groups.

RESULTS: Patients in Group RD had significantly longer duration of sensory block (202.90 ± 50.2 min) compared to Group RN (157.33 ± 31.6 min), P < 0.001. Time to first rescue analgesia request was significantly longer in the Group RD compared to Group RN (265.16 ± 71.4 min vs 203.67 ± 35.6 min, respectively) ( P < 0.001). However, the sensory block onset, maximum block height, time to two dermatomal regression, and motor block intensity remained unaltered. Incidence of side effects like hypotension, bradycardia, nausea, vomiting, and shivering were statistically similar in both the groups.

CONCLUSION: Addition of 5 μg dexmedetomidine enhances the analgesic effect of intrathecal 18.75 mg isobaric ropivacaine for the conduct of fracture neck of femur surgeries with minimal adverse events.