Nerve injury due to peripheral nerve blocks: Pathophysiology and aetiology

Permanent nerve injury as a complication of peripheral regional anaesthesia is fortunately rare with an estimated incidence of 0,03%. However, transient neurological symptoms are more frequent with an occurrence of 3-8%. The pathophysiology and etiology of nerve injury depends on a number of different factors. The needle-nerve trauma, cytotoxicity of local anaesthetics, patient factors (i.e. morbidity) and factors which are related to surgical interventions should be considered. Regarding pathophysiology, trauma-related inflammation should be acknowledged as an important interference during nerve recovery. Needle-nerve contacts, nerve perforation and local cytotoxicity of local anaesthetics should be reduced to a minimum by application of nerve stimulation, ultrasound and an adequate dosage of local anaesthetics with less locotoxicity.