Establishing scales of perceived severity for clinical situations during anaesthesia.

BACKGROUND In many clinical, teaching, and research situations it would be useful to have graded scales of the urgency or other subjective properties for clinical situations that can arise during anaesthesia. Such a scale could serve as a reference point for the appropriate mapping of the urgency in audible alarms or visual warnings, provide a basis for training of graduated difficulty during anaesthesia simulation, provide a benchmark in risk assessment exercises, guide prioritization of decisions in computerized decision support systems for anaesthesia and help in assessing anaesthetist occupational stress. METHODS A questionnaire-based instrument was developed to assess the perceived severity of a range of anaesthetic clinical situations. Four scales were tested: the severity of the situation for the patient, the urgency of response required by the anaesthetist, attention required by the anaesthetist, and anxiety experienced. Over 300 anaesthetists in three cohorts of 100 were consulted in the selection of the situations to be studied. The final version of the questionnaire, which included 25 situations, was circulated to a further 229 anaesthetists for validation. The pair-wise relationships of the four properties and hence their independence, was examined using Kendall's tau and correlation analysis. RESULTS The subjective assessments of urgency and attention were closely related, as were severity and anxiety. Comparing the mean rank for the severity scale with the subjective risk scores revealed a statistically significant correlation of tau=0.647 (P<0.01). CONCLUSION Subjective assessment of severity by anaesthetists was found to be consistent across the clinical situations studied.