Although the above listed durations are printed in the prescribing guidelines it is also true that many therapeutic blocks last much longer than the duration of the times listed. The mechanisms underlying these processes are not completely understood. At time repetitive blocks - daily or weekly can result in pain relief that may last weeks or months. Bupivacaine is relatively free of side effects when given in the right dose and in the right location. Often the landmarks for identifying specific locations for nerve blocks are located near bony or vascular landmarks.
Side effects associated with bupivacaine are systemic toxicity from high blood levels of the drug.
Bupivacaine easily crosses the placenta and should be uses with caution during pregnancy. Churchill Livingstone Inc.