Maria Mikela Chatzimichailidou

A Comparison of the Bow-Tie and STAMP Approaches to Reduce the Risk of Surgical Instrument Retention

Although relatively rare, surgical instrument retention inside a patient following central venous catheterization still presents a significant risk. The research presented here compared two approaches to help reduce retention risk: Bow-Tie Analysis and Systems-Theoretic Accident Model and Processes. Each method was undertaken separately and then the results of the two approaches were compared and combined. Both approaches produced beneficial results that added to existing domain knowledge, and a combination of the two methods was found to be beneficial. For example, the Bow-Tie Analysis gave an overview of which activities keep controls working and who is responsible for each control, and the Systems-Theoretic Accident Model and Processes revealed the safety constraints that were not enforced by the supervisor of the controlled process. Such two-way feedback between both methods is potentially helpful for improving patient safety. Further methodology ideas to minimize surgical instrument retention risks are also described.

Beyond monitors: distributed situation awareness in anaesthesia management

ABSTRACT In this study, the construct and the role of distributed situation awareness (DSA) on the anaesthetic management of challenging major obstetric haemorrhage (MOH) cases is explored, specifically the anaesthetists perception of the operating theatre elements, the understanding of their meaning and the anticipation of their progress in interaction with other people and artefacts. Eighteen anaesthetists from four Scottish Hospitals were asked to discuss a challenging MOH case from their experience, prompted by questions emanating from a critical decision method protocol. The majority of the described DSA references were attributed to gathering information and in interaction with external artefacts, including monitors, suction containers, the whiteboard and even swabs. For understanding and anticipating, the majority of DSA references emerged in interaction with other team members within and outside the operating theatre. Methods for improving practice and training in MOH should address the interactive nature of DSA, by going beyond monitoring anaesthetic displays.

RiskSOAP: On the Relationship Between Systems Safety and the Risk SA Provision Capability

It is generally accepted that there is a relation between safety and awareness. Yet, there is no quantitative evidence for this relationship because the correlated entities are difficult to be quantified. This paper responds to this challenge by measuring the “risk situation awareness (SA) provision (RiskSOAP) capability.” According to the complex sociotechnical system design and development, there is an inherent capability of each system part to provide its agent with SA about the presence of system threats and vulnerabilities, possibly leading to accidents. This capability is called herein “risk SA” and stems from the number, type, and characteristics of the elements that shape the system parts; laying the foundation for the emergence of risk SA on a system level. Under this notion, this paper adopts the RiskSOAP methodology as a means to quantify the different states of a system in terms of its RiskSOAP capability, using the Überlingen mid-air collision accident as a case study. The case study results showed that the RiskSOAP capability degrades while the system is headed to the accident state. This is attributed to the presence of flaws in the system involved in the Überlingen accident. This study also offers insight to the limitations of the proposed methodology and suggests the future work to overcome them.