Abstract
A simple schema of anaesthesia system error evolution is described. This was used, with a modified critical incident technique, as a framework for data gathering and error analysis. The outline places emphasis on recovery pathways and, in addition to causal and contributory factors, was able to identify many factors which aided or hindered the processes of error detection, diagnosis and management. On average, 8.1 factors were identified which were considered to have significantly influenced the genesis and evolution of each reported error. Differences were apparent in the type of factors which determined error production and aspects of the recovery sequence. The described schema is suggested to be of value for data generation, and as a tool for discussion as part of anaesthesia quality assurance.