Sonolocation guided axillary brachial plexus block using bupivacaine and hyperbaric bupivacaine in goats

The present clinical study evaluated the efficacy of bupivacaine HCl (0.5%) and hyperbaric bupivacaine (0.5%) for axillary brachial plexus block (BPB) in 12 goats (six in each group) under ultrasonographic guidance with the aid of peripheral nerve stimulator (PNS). The axillary brachial plexus was identified as three rounded hyperechoic structures with axillary artery as pulsative hypoechoic structure kept as land mark with the use of 7.5–10 MHz linear ultrasound transducer, also located with the maximum muscle twitching at 0.4 mA current with the aid of peripheral nerve stimulator in all animals. Axillary BPB performed using bupivacaine HCl (0.5%) showed complete BPB @ 3.0 mg/kg b.wt in five goats with mean full onset of 180±40 min; whereas all the six goats, wherein hyperbaric bupivacaine was used, showed complete BPB @ 3.0 mg/kg b.wt with mean full onset of 100±40 min. Bupivacaine HCl provided longer duration of action for axillary BPB as compared to hyperbaric bupivacaine. Hyperbaric bupivacaine takes shorter time for onset of axillary BPB without any complications as compared to bupivacaine HCl. Ultrasonography provides good visualization of axillary brachial plexus with the aid of peripheral nerve stimulator.