Neurological complications following central neuraxial blocks: are there predictive factors?

Severe complications such as spinal epidural haematoma and an array of adverse neurological events leading to temporary or permanent disability have been ascribed to central neuraxial blocks. Infections (meningitis, abscesses), chemical injuries and very rarely cerebral ischaemia or haemorrhage, or both, have also been ascribed directly or indirectly to spinal and/or epidural anaesthesia. Some case reports, and very few retrospective studies, have focused their attention on the fact that central nerve blocks can cause, albeit rarely, permanent damage to the spinal cord or nerve roots, or both. The cause of this damage in many cases remains unclear. The attention of investigators and practitioners is focused both on understanding the causative mechanisms of such accidents and in identifying 'alarm events' that can arise during the administration of a central block, if any. We reviewed the international literature for the neurological complications of central neuraxial blocks to identify some events that, if they occurred during the block procedure, could be perceived as dangerous.