Background and Aims Anatomical variation in the interscalene brachial plexus is not uncomman but can cause difficulty in identifying the structures even on ultrasound.^1,2,3

Here we present a case report of one such anatomical variation encountered while performing ultrasound guided interscalene brachial plexus block and how we overcame our challenges.

CASE REPORT A 58 yr old male who was premorbidly healthy was posted for philos plating (orif # head of the humerus). Position proposed for surgery was supine. Decision was taken to give ultrasound (USG) guided interscalene brachial plexus block(ISB). On ultrasound scanning of the interscalene area the plexus was seen as the C5 C6 roots on the surface of the anterior scalene muscle whereas the C7 in the interscalene groove(image as below)

• Download figure
• Open in new tab
• Download powerpoint

Abstract B72 Figure 1

• Download figure
• Open in new tab
• Download powerpoint

Abstract B72 Figure 2

The challenges in front of us were: 1.100% phrenic nerve palsy eminent 2.block failure

We decided to go ahead with the interscalene block . 5 ml of 0.5% bupivacaine was given at the C5-C6 roots and 5 ml of 0.5% bupivacaine was given at the C7 root. The plexus was traced to the supraclavicular area and 10 ml of 0.5% bupivacaine was administered at the supraclavicular brachial plexus. The patient was given head low position. The block was assessed every 10 min for the next 30 mins.

Results We could achieve motor and sensory block adequate for surgery without supplementation of additional local anaesthetic and sedation. No complications occurred.

Conclusions Anatomical variation of the interscalene brachial plexus is challenging but with proper planning block failure can be avoided.