Dexmedetomidine and clonidine as adjuvants in epidural anaesthesia: A comparative evaluation
Author(s): Dr. Mukkapati Koteswara Rao
Abstract:Introduction: Epidural administration of α-2 adrenergic agonist is associated with sedation, analgesia, anxiolysis, hypnosis and sympatholysis. Clonidine has been used successfully over the last decade for the said purpose and the introduction of dexmedetomidine has further widened the scope of α-2 agonists in regional anaesthesia.
Objectives: The purpose of this study was to compare the clinical profile and efficacy of two alpha 2 agonists dexmedetomidine and clonidine when administered epidurally as an adjuvant to Bupivacaine in patients undergoing elective infraumbilical and lower limb surgeries.
Methods: A prospective randomized double blind controlled study was planned. 60 patients of ASA I & II physical status aged between 18-60 yrs who underwent elective infraumbilical and lower limb surgical surgery from 1st of January 2019 to 31st of November 2020 and satisfying all the inclusion criteria were enrolled in the study and were randomly allocated into two groups.
Group A (n=30) = patients received 0.5% isobaric bupivacaine 15 ml with dexmedetomidine 1µg/kg.
Group B (n=30) = patients received 0.5% isobaric bupivacaine 15ml with clonidine 2µg/kg.
Results: Addition of dexmedetomidine to bupivacaine as an adjuvant resulted in an earlier onset of sensory analgesia at T10 as compared to the addition of clonidine. Dexmedetomidine not only provided a higher dermatomal spread but also helped in achieving the maximum sensory anaesthetic level in a shorter period compared to clonidine Modified Bromage scale 3 was achieved earlier in patients who were administered dexmedetomidine as an adjuvant. All these initial block characteristics turned out to be statistically significant values on comparison. Dexmedetomidine is a popular sedative agent nowadays and similar findings were observed in our study as well. Mean sedation scores were significantly higher in Dexmedetomidine group compared to Clonidine group. Dexmedetomidine provided a smooth and prolonged post-operative analgesia as compared to clonidine. Time to two segmental dermatomal regression as well as return of motor power to Bromage 1 was significantly prolonged in dexmedetomidine group. As a result patients in clonidine group required rescue analgesia earlier than dexmedetomidine group.
Conclusion: Dexmedetomidine is a better adjuvant than clonidine in epidural anaesthesia because of better sedation, anxiolysis, superior intraoperative and postoperative analgesia and stable cardio-respiratory parameters.