A multicentre comparison of the mental workload and non-technical skills of trainees during routine anaesthetic practice.
Byrne, Turner, Lewis, Chawathe, Thomas
Non-technical skills (NOTECH) and mental workload are recognised as ket determinants of safe practice within high risk industries. Mental workload may be a key factor in safety and there may be an association between it and NOTECH.
Individuals have a finite ability to process information (mental workload) and if the demands of a task exceed that ability, poor performance or error is likely.
The aim of this study was to measure the mental workload and NOTECHs of trainee anaesthetists during routine practice and determine their relationship.
A single procedure with limited co-morbidity was chosen (elective Caesarean delivery, CD) as case complexity has been shown to influence mental workload.
After institutional research and ethics review, subjects recorded their grade, years of training, had an iPhone attatched to their upper arm and then completed the case. The consultant acted as observer, intervening only to ensure patient safety. The subjects' mental workload was estimated by the time taken to respond to vibrotactile stimulus delivered between every 30-90seconds. Delays greater than 1350ms were considered to be due to cognitive overload. The performance of the subjecs was observed by a consultant and scored using the ANTS assesment tool, using 4 domains, with a maximum score of 16.
Twenty four cases were completed in 3 centres with 4 supervisors who each supervised at least 3 cases. All the consultants completed formal assessments regularly but had received no training in the use of the ANTS tool. The average overall rating was 13.96 out of 16 (range 12-16) with 9 subjects scoring 16 and with all supervisors scoring at least one subject as 16/16. In all cases, the subject's response times were recorded.
When ANTS rating and mental workload of each subject was compared there was no clear relationship betwen the two. Correlation coefficient: 0.252 (P=0.247, n=23)
This study failed to find a relationship between measured mental workload and NOTECH during elective CD. Our conclusions are that the assesors were inadequately trained and assigned ratings which did not reliably identify poor performance and therefore masked any possible relationship.
We suggest that the assessments of ANTS should not be undertaken by staff without prior training. The measurements of mental workload were consistent with previous publications and charachterised the delivery of anaesthesia as a high workload task with significant risk of cognitive overload.