OBJECTIVE: Levobupivacaine is S-enantiomer of bupivacaine with similar onset and duration of sensory and motor block but has less CNS and cardiac toxicity. Various adjuvants have been used with local anesthetics to obtain adequate level of anesthesia together with more stable hemodynamics. Opioids such as fentanyl are commonly being used while Dexmedetomidine, a new highly selective 2 agonist, is under evaluation as a neuraxial adjuvant. The aim of the study was to evaluate onset and duration of sensory and motor block, hemodynamic effects, postoperative analgesia and adverse effects of dexmedetomidine or fentanyl given intrathecally with 0.5% levobupivacaine

METHOD: The study was conducted in Department of Anesthesia, SMS Medical College, Jaipur. It was hospital based, randomized, double blind, controlled study. 90 patients of ASA grade 1/ 2, scheduled for elective infraumblical surgery (abdominal hysterectomy, appendicectomyetc), were randomly allocated to receivelevobupivacaine 12.5mg (group A), or levobupivacaine 12.5mg + fentanyl 25 μg (group B), or levobupivacaine 12.5mg + dexmedetomidine 5 μg (Group C). Levobupivacaine was made hyperbaric by adding 1ml of 25% dextrose. (Total volume=4ml). Statistical analysis: by ANOVA and Chi-square test. RESULTS: Patients in Dexmedetomidine group had a significantly longer sensory and motor block times as compared to the other two groups (p<0.001). The duration of analgesia was also significantly prolonged in Dexmedetomidine group (259.4±12.8 min) than the fentanyl (161.8±8.5) and control (114.0±14.3) groups (p=0.0000).

CONCLUSION: Intrathecaldexmedetomidine is associated with prolonged sensory and motor block and increased duration of postoperative analgesia as compared to fentanyl and control group.