Anaesthesia General 837376a3 Pneumothorax is a complication of A Axillary block B Brachial plexus block C Epidural block D High Spinal block High-Yield Explanation B i.e. Brachial Plexus block Brachial plexus block with interscalene approach provides most intense anesthesia in C5-C7 dermatomes and least intense in C8-T1 (ulnar nerve) area.