Background and aims This case series aimed to evaluate the effect of onset times of sensory anaesthesia in median, radial, ulnar and musculocutaneous nerves when 15 ml of 0.5% Ropivacaine was used in ultrasound guided costoclavicular brachial plexus block anaesthesia for forearm surgeries.

Methods After obtaining written informed consent, a series of 11 patients were given 15 of 0.5% Ropivacaine in ultrasound guided costoclavicular brachial plexus block. The block needle was placed at the centre of the lateral and posterior cords under ultrasound guidance. Sensory testing was done using Pin Prick test at 0-, 5-, 10-, 15-, 20-, 25- and 30-min intervals in areas supplied by the median, radial, ulnar and musculocutaneous nerves. The response was assessed using the Numeric Rating Scale of 0 to 100. NRS <30 was considered as cut-off of onset of sensory block. Statistical analysis was expressed as Mean +-Standard Error.

Conclusions We conclude that 15 ml of 0.5% Ropivacaine appears enough volume for onset of surgical anaesthesia in ultrasound guided costoclavicular brachial plexus block, thus cutting down on the total dose administered. However, further studies with better design are required to validate the findings.