Specific blocking of the ulnar and median nerve causes substantial increases in T(s) in specific areas of the hand. In contrast, the specific blocking of the musculocutaneous or radial nerve does not increase T(s). Further studies are needed to clarify if these findings can be used to objectively evaluate brachial plexus block success.

We describe a new ultrasound-guided technique to specifically block the axillary nerve. The potential clinical role of this new block remains to be determined.

Four different thermographic patterns were found. Simultaneous increases in skin temperature of both the 2nd and 5th digits predicted lateral infraclavicular block success with a positive predictive value of 100%. Digit skin temperature ≤ 30 °C 30 min after performing the block indicated block failure.

We found that a qualitative difference in skin temperature between the blocked and nonblocked hands, measured distally on the 2nd and 5th digits, was a valid and reliable diagnostic test for predicting successful lateral infraclavicular block.