Prevention
Correct techniche,careful and repeated aspiration and the use of a test dose are important,but the main safety measure is slow injection of the local anaesthetic.This prevents rapid production of very high plasma concentrations even if the injection is intravascular.By this means,toxicity may be diagnosed early,the injection discontinued and a major reaction avoided.Fast injection of local anaesthetic is not necessary for the performance of any block.
_____Textbook of Anaesthesia Chapter 25