Search PubMedSearch

Biomedical subjects

J Reason

Publications and source records attributed to J Reason.

6 recordsLinked to original sources

Accident analysis of large-scale technological disasters applied to an anaesthetic complication.

The occurrence of serious accidents in complex industrial systems such as at Three Mile Island and Bhopal has prompted development of new models of causation and investigation of disasters. These analytical models have potential relevance in anaesthesia. We therefore applied one of the previously described systems to the investigation of an anaesthetic accident. The model chosen describes two kinds of failures, both of which must be sought. The first group, active failures, consists of mistakes made by practitioners in the provision of care. The second group, latent failures, represents flaws in the administrative and productive system. The model emphasizes the search for latent failures and shows that prevention of active failures alone is insufficient to avoid further accidents if latent failures persist unchanged. These key features and the utility of this model are illustrated by application to a case of aspiration of gastric contents. While four active failures were recognized, an equal number of latent failures also became apparent. The identification of both types of failures permitted the formulation of recommendations to avoid further occurrences. Thus this model of accident causation can provide a useful mechanism to investigate and possibly prevent anaesthetic accidents.

Accidents

The contribution of latent human failures to the breakdown of complex systems.

Several recent accidents in complex high-risk technologies had their primary origins in a variety of delayed-action human failures committed long before an emergency state could be recognized. These disasters were due to the adverse conjunction of a large number of causal factors, each one necessary but singly insufficient to achieve the catastrophic outcome. Although the errors and violations of those at the immediate human-system interface often feature large in the post-accident investigations, it is evident that these 'front-line' operators are rarely the principal instigators of system breakdown. Their part is often to provide just those local triggering conditions necessary to manifest systemic weaknesses created by fallible decisions made earlier in the organizational and managerial spheres. The challenge facing the human reliability community is to find ways of identifying and neutralizing these latent failures before they combine with local triggering events to breach the system's defences. New methods of risk assessment and risk management are needed if we are to achieve any significant improvements in the safety of complex, well-defended, socio-technical systems. This paper distinguishes between active and latent human failures and proposes a general framework for understanding the dynamics of accident causation. It also suggests ways in which current methods of protection may be enhanced, and concludes by discussing the unusual structural features of 'high-reliability' organizations.

Accident Prevention

Absent-mindedness in shops: its incidence, correlates and consequences.

This paper describes a questionnaire study of absent- mindedness in shops, and an analysis of 166 letters written by 67 individuals who felt themselves to be wrongly accused of shoplifting . A total of 150 men and women were asked how often they had experienced each of 24 varieties of mental lapse while shopping. If they had not actually suffered a particular lapse, they were asked to judge its likelihood of occurrence. Approximately half of the sample also completed the Cognitive Failures Questionnaire ( CFQ ). Lapses carrying the risk of shop-lifting accusations were reported as occurring far less frequently, and were judged as less likely, than either ' embarrassing ' or 'nuisance' lapses. However, an examination of the circumstances leading up to accusations of shoplifting indicated that high risk lapses can occur when ill health, extreme preoccupation and distraction are combined with unwise supermarket practices. A positive and significant correlation was found between the CFQ and the Absent- Mindedness in Shops Questionnaire ( AMSQ ). A factor analysis of the AMSQ revealed a very pervasive general factor, together with a risk appreciation factor. The findings supported the view that responses to both the CFQ and the AMSQ reflected characteristic differences in the management of some superordinate attentional control resource.

Adolescent

A visually-driven postural after-effect.

Viewing a large-scale moving scene typically causes a free standing observer to lean in the direction of the seen motion. It was also noted that when the visual motion ceases, the observer drifts back toward the upright position, but instead of this body movement stopping at the vertical, it tends to continue so that the observer remains leaning in the opposite direction for several seconds before finally returning to the upright. The two experiments reported here were designed to investigate the determinants of this postural after-effect in relation to a pitch vection stimulus. Our findings clearly showed that the after-effect was dependent upon (1) the establishment of a prior visually-induced body lean, and (2) sight of the static display on the cessation of motion. The notion of an internalised representation of body position was invoked to account for these results.

Adult

Intravenous iron-dextran: studies on unsaturated iron-binding capacity.

A method is described for measuring the plasma unsaturated iron-binding capacity in the presence of very high concentrations of iron as iron-dextran. The procedure utilizes (59)Fe to label the apotransferrin with subsequent separation of ionic iron from transferrin-bound iron on an ion exchange or Sephadex G.25 column. The unsaturated iron-binding capacity has been measured in rabbits and dogs after intravenous injection of iron-dextran and in human subjects after total dose infusion of iron-dextran. No evidence of saturation of the unsaturated iron-binding capacity was found even when the plasma iron values were greater than 40,000 mug Fe/100 ml.

Animals