Upper limb blocks.

This article discusses recent innovations and changes in practice in upper limb regional anaesthesia, dividing the blocks into those performed above the clavicle, those performed in the area of the clavicle and those performed below it. It offers a critical appraisal of the current status with regard to the use of ultrasound nerve location for upper limb regional anaesthesia and, while accepting that the use of ultrasound in this way has many theoretical advantages and will therefore continue to grow, concludes that there is currently insufficient published evidence to determine conclusively that the use of this technique is associated with nerve blocks that are more successful or safer.