Objective: Clonidine has been used as adjuvant to local anesthetics in
order to extend the duration of analgesia in various regional and
central neuraxial blocks. It is previously reported that clonidine
added to bupivacaine increases analgesia duration in brachial plexus
block. We evaluated the effect of this combination in supraclavicular
brachial plexus block for upper limb orthopedic procedures. Materials
and Methods: A randomized double-blind placebo controlled trial was
done with 70 patients of American Society of Anesthesiologists Grade I
or II status undergoing upper limb orthopedic procedures. Group A (n =
35) patients received 25 ml of 0.5% bupivacaine and 0.2 ml (30 mcg)
clonidine, whereas group B (n = 35) received 25 ml of 0.5% bupivacaine
and 0.2 ml normal saline through a supraclavicular approach for
brachial plexus block. Vital parameters were recorded 10 min prior to
block placement and every 3 min thereafter till the end of the
procedure. Onset and duration of both sensory and motor blocks and
sedation score were recorded. All patients were observed in
postanesthesia care unit and received tramadol injection as soon as
they complained of pain as rescue analgesic. Duration of analgesia was
taken as the time from placement of block till injection of rescue
analgesic. Results: Analgesia duration was 415.4 ± 38.18 min (mean
± standard deviation) in Group A (clonidine) compared to 194.2
± 28.74 min in Group B (control). No clinically significant
difference was observed in heart rate, blood pressure, and oxygen
saturation. Sedation score was higher in the clonidine group.
Conclusion: Addition of a small dose of clonidine to 0.5% bupivacaine
significantly prolonged the duration of analgesia without producing any
clinically important adverse reactions other than sedation