A national census of central neuraxial block in the UK: results of the snapshot phase of the Third National Audit Project of the Royal College of Anaesthetists

The first stage of the Royal College of Anaesthetists Third National Audit Project to assess the incidence of major complications of central neuraxial block in the UK was a 2-week national census of block use. A reporting system was established in the 309 National Health Service hospitals believed to undertake surgical work and data were received from 304, a response rate of 98.7%. Over 90% of these were judged by the reporters to be 'accurate'. The total number of procedures reported as being performed in the 2-week period was 27 533: extrapolation using a multiplier of 25 suggests that nearly 700 000 major blocks are performed annually (315 000 spinals, 287 000 cervical, thoracic or lumbar epidurals, 42 000 combined spinal-epidurals and 56 000 caudal epidurals). After the second stage of the project, which will record complications from the same hospitals over a 12-month period, these data will be used as denominators to calculate the incidences of complications.