A comparison of efficacy of parenteral and perineural dexmedetomidine with 0.25% ropivacaine for post-thyroidectomy analgesia using bilateral superficial cervical plexus block.

BACKGROUND AND AIMS: Opioids are conventionally used for post-thyroidectomy pain, regional anesthesia is becoming popular due to its feasibility and efficacy in minimizing use of opioids and hence its side effects. This study compared analgesic efficacy of bilateral superficial cervical plexus block (BSCPB) using perineural and parenteral dexmedetomidine with 0.25% ropivacaine in thyroidectomy patients.

MATERIAL AND METHODS: In this double-blind study, 60 American Society of Anesthesiologists (ASA) physical status I and II thyroidectomy patients, aged 18-65 years were randomized into two groups. Group A ( n = 30) received BSCPB with 0.25% ropivacaine, 10 mL on each side with dexmedetomidine 0.5 μg/kg IV infusion. Group B ( n = 30) received 0.25% ropivacaine plus dexmedetomidine 0.5 μg/kg, ten mL on each side. Duration of analgesia by measuring pain visual analog scores (VAS), total dose of analgesic requirement, Haemodynamics parameters and adverse events were recorded for 24 h. Categorical variables were analyzed using Chi-square test and continuous variables were computed as mean with standard deviation and analyzed using independent sample t -test. Mann-Whitney U test was used for analysis of ordinal variables.

RESULTS: Time to rescue analgesia was longer in Group B (18.6 ± 3.27 h) as compared to Group A (10.2 ± 2.11 h) ( P < 0.001). Total analgesic dose required was also found to be lesser in Group B (50.83 ± 20.37 mg) as compared to Group A (73.33 ± 18.27 mg) ( P < 0.001). No significant hemodynamic changes or side effects were observed in both groups; ( P > 0.05).

CONCLUSION: Perineural dexmedetomidine with ropivacaine in BSCPB significantly prolonged the duration of analgesia with reduced rescue analgesic requirement.