New trends in regional anaesthesia.

In this review, some of the newer developments in regional anaesthesia (RA) are discussed. The relationship between paraesthesiae and nerve stimulator responses has been shown to be unclear, and sometimes at a needle tip location where a paraesthesia is found, there is no response to the nerve stimulator. It is recommended to use whichever end point is found first. The debate as to the safety of RA in anaesthetised patients remains unresolved and strong opinions are often based on individual case reports. The training and skill of the anaesthetist still appears to be a more important factor. The problems of RA and impaired coagulation are well understood and guidelines are in place in many countries. The value of neuraxial blocks for postoperative pain management is well established and the increasing use of peripheral nerve blocks often using continuous methods is to be encouraged. The use of PCA for blocks as well as intravenously and the extension of the use of RA into the home are important developments. The beneficial effects of RA on postoperative morbidity and mortality are becoming clearer, and the introduction of the two new local anaesthetic agents, ropivacaine and levobupivacaine have improved safety. There has, however, been very slow progress in the development of long awaited ultralong acting local anaesthetics or in the introduction of slow release formulations.