Anaes · Neuraxial anaesthesia

Neuraxial anaesthesia

Also known as Spinal anaesthesia · Epidural anaesthesia · Central neuraxial block · CSE · NAP3

Neuraxial anaesthesia — the spinal, the epidural and the combined spinal-epidural — produces a reversible blockade of the spinal nerve roots and the spinal cord by the injection of a local anaesthetic (with or without an adjuvant) into the subarachnoid space (the spinal) or the epidural space (the epidural). The framework rests on four exam-critical ideas: the physiology of the block (the local anaesthetic blocks the nerve roots in a dose-dependent, length-dependent pattern, with the sympathetic fibres blocked first and the motor last); the principal acute complication is the hypotension from the sympathetic block, prevented by the vasopressor and the fluid; the principal serious complications are the epidural haematoma, the epidural abscess and the nerve injury, whose incidence is documented by NAP3 as rare but potentially devastating; and the anticoagulated patient requires the strict observance of the ASRA guidelines on the timing of the neuraxial technique relative to the anticoagulant. Built on the NAP3 national audit (Cook 2009), the ASRA anticoagulation guidelines (Horlocker 2010, Narouze 2018), and the obstetric neuraxial complications study (Tunn 2025).