ABSTRACT : This study was conducted to compare the efficacy, cardio-respiratory effects, time to achieve and terminate sedation and post operative analgesia of equi-sedative doses of dexmedetomidine and propofol in patients undergoing surgical procedure under regional anaesthetic blockade.

METHODS : After obtaining approval from ethical committee present study was conducted on 80 adult educated mentally stable patients of either sex, with the age group of 20-60 years undergoing elective surgery( duration=1-2 hours) under regional anaesthesia (epidural, spinal or peripheral nerve block). The patients were randomly allocated in two groups- Group A patients (n=40) received dexmedetomidine 1μg/kg initial loading dose for 10 min+maintenance 0.5-0.7 μg/kg/hr and Group B patients (n=40) received propofol 75 μg/kg/min for 10 min+maintenance 30-60 ug/kg/min. Study drugs were titrated to achieve Intra operative sedation levels with Bispectral Index Score( BIS) of 70-80 and Observer’s Assessment of Alertness/ Sedation Scores( OAA/S) of 3 and then stopped at 60 minute. Visual Analog Scale (VAS) was recorded pre and postoperatively. Monitoring of BIS, OAA/S, pulse, MAP, SpO2 and RR were done every 5 min intervals during the intra operative period and then in recovery room at 5 min, 20 min, 35 min, 50 min & 65 min. Unpaired t test were performed for analysis.

RESULTS : In group A, BIS of 70-80 and OAA/S of # was achieved at 25 minute and in group B at 15 minute. The mean HR and MAP decreased in both the groups intraoperatively but postoperatively they reached baseline in group B but remained lower in group A till 65 minute.Inpost operative period the value of OAA/S after 5 min was lower( 4.22±0.42) in group I as compared to group II (4.45±0.50). postoperatively VAS score was 3.5 in group A but 8.8 in group B.

CONCLUSIONS :Dexmedetomidine produces sedation comparable to propofol with a slower onset and offset. Dexmedetomidine has an postoperative analgesic effect upto one hour with VAS score of 3.5 as compared to propofol which had VAS score of 8.8. Postoperatively HR and MAP reaches baseline with propofol but remains lower with dexmedetomidineupto one hour.