Blocs nerveux périphériques, paresthésies et injections intraneurales

Myelinated or unmyelinated nervous fibres are distributed into bundles wrapped by several membranes i.e.endoneural, epineural and perineural membranes. Nerve compression or trauma induces a series of nerve potentials leading to parestesias persisiting as lon as the nerve lesion. Short bevel needles may induce less frequent but more severe nerve lesions. Ultrasound guidance documents that intraneural local anaesthetsic solution injection are common but do not lead systematically to nerve damage. Ultrasound imaging may allow to correlate the site of local anaesthetic injection with the occurence of nerve lesion improving safety of peripheral blocks.