ABSTRACT:

BACKGROUND: The purpose of this study is to compare the duration of sensory and motor block in  elective lower limb and abdominal procedures following intrathecal administration of bupivacaine along with adjuvants either clonidine or dexmedetomidine.
METHODS: A prospective randomised double blinded study. 120 study participants were randomly allocated to three groups-Group A was given 12.5 mg of hyperbaric bupivacaine, Group B was given 3 mcg dexmedetomidine along with 12.5 mg hyperbaric bupivacaine and Group C was given 30 mcg of clonidine along with hyperbaric bupivacaine. The duration of sensory and motor block was recorded. 
RESULTS: Group B and C study participants showed significantly longer duration of sensory and motor block when compared to Group A. The mean duration of sensory block in Group A was 92.5 minutes, Group B 124.5 minutes Group C (119.4 minutes) (A vs B, A vs C p<0.001). The mean duration of motor block in group A 149.1 min, group B 252.5 min, Group C 217 min (A vs B, A vs C, B vs C P<0.001)
CONCLUSION: By adding 3 mcg dexmedetomidine or 30 mcg clonidine to hyperbaric bupivacaine duration of sensory and motor block was significantly prolonged.

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