Addition of intrathecal midazolam to bupivacaine produces better post-operative analgesia without prolonging recovery.

OBJECTIVE

The administration of midazolam by centroneuraxis route has been shown to produce segmental antinociception. This midazolam analgesia was found to enhance the effects of local anesthetics given in combination epidurally without any adverse effects. The present study was designed to evaluate the post-operative analgesic effect of intrathecal midazolam-bupivacaine mixture in patients undergoing knee arthroscopy.

METHODS

Thirty healthy patients scheduled for knee arthroscopy were divided into two groups to receive either midazolam-bupivacaine mixture (group M; n = 15) or bupivacaine alone (group B; n = 15) intrathecally. Level of sensory block, sedation score, assessment of pain using visual analogue score were recorded in both groups at regular time intervals. Time to block regression, recovery to ambulation and ability to void were recorded and noted before discharge.

RESULTS

A significantly higher VAS score was seen in group B patients as compared to the score observed in group M patients before discharge (p<0.05). All patients received rescue analgesia in group B at a mean duration of 258 +/-46.8 minutes whereas only one patient in group M required supplemental analgesia within this period. Time to regression of sensory analgesia to L5-S1 level was longer in group M (267+/-67.38) as compared to group B (229.8+/-41.4) (p<0.05). Blood pressure, heart rate, oxygen saturation and sedation score showed no differences between the groups. Neither motor block nor time to void were prolonged with the addition of midazolam to bupivacaine.

CONCLUSION

The results suggest that addition of midazolam to bupivacaine intrathecally provided better post-operative analgesia without any adverse effects.