The emergency department response to chemical, biological, radiological and nuclear events: a human factors and ergonomics approach

Since the September 11, 2001 terrorist attacks in the USA, government agencies and professional societies have focused greater attention towards the hospital response, particularly Emergency Departments (EDs), for emergency preparedness and response. In the UK, the Civil Contingencies Act lays out responsibilities on NHS organisations to uphold civil protection.

The ED is a complex, hectic, and high-pressured environment. Chemical, Biological, Radiological, and Nuclear (CBRN) events are multi-faceted emergencies and present numerous challenges to ED staff (first receivers).

This thesis used Hierarchical Task Analysis (HTA) to explore whether there were differences between operational procedures and practice using the Human Factors/Ergonomics (HF/E) approach for Work as Imagined (WAI; procedures) and Work as Done (WAD; practice). The aims were to 1) Explore whether HTA could be used to map complex socio-technical systems and 2) Make recommendations to improve the ED response to CBRN events.

Study 1 (WAI) took a top down approach for document analysis of standard operating procedures (emergency plans) at two Type 1 NHS Trust EDs. The plans were analysed thematically to create colour coded HTA representations of the CBRN plans. Differences in General Organisational Responsibilities (GORs) were found between the two Trusts; Trust A had 13 GOR themes and Trust B had 20 GOR themes, of which 13 overlapped. The emergency plans include role-specific action cards used to support individual tasks; each card (n=30) was analysed and represented as HTAs. An Ergonomics review of the HTAs as part of the coding process produced higher level (standardised) themes at both Trusts as:

1. Prepare to respond to CBRN incident (Trust A and B).

2. Respond to CBRN incident (Trust A and B).

3. Initiate recovery from CBRN incident (Trust A).

4. Document CBRN incident (Trust A).

Study 2 (WAD) collected data with semi-structured interviews from 57 first receivers. Scenario cards were used as prompts to explore clinical and operational practice. The field notes were converted to HTAs and thematically analysed. The synthesis of these themes provided a bottom up perspective to consider standardisation based on WAD (how first receivers respond to CBRN events). Similarities between the Trusts were evident in the importance placed on actions for isolate and contain, liaise and communicate, and escalate. Differences were found in the importance placed on Personal Protective Equipment (PPE), decontamination, treatment, and investigation of the presentation. The results for WAI and WAD were compared. WAI focused on actions such as documentation, checking, and timing; WAD prioritised patient needs through assessment, treatment, and diagnosis. Finally, the findings were synthesised into standardised recommendations as:

• A CBRN planning checklist.

• Action card template.

• Example of a meso-system.

• CBRN response framework.

The WAI vs WAD framework provided a robust theoretical framework to identify gaps and improvement opportunities in the ED CBRN response. This research shows that HTA can be used to unpack a multifaceted event in a complex environment.