Delayed flow is a risk to patient safety: A mixed method analysis of emergency department patient flow

•Extended time to see the triage nurse compromised patient safety.•During crowding patients were assessed and treated in makeshift spaces.•Access block contributed to care delays, ramping, and further ED crowding.•ED staff demonstrated professionalism, efficiency and ability to cope during crowding.•The number of presentations may not be a predictor of prolonged ED length of stay. Increasing emergency department (ED) demand and crowding has heightened focus on the need for better understanding of patient flow. This study aimed to identify input, throughput and output factors contributing to ED patient flow bottlenecks and extended ED length of stay (EDLOS). Concurrent nested mixed method study based on retrospective analysis of attendance data, patient flow observational data and a focus group in an Australian regional ED. Analysis of 89 013 ED presentations identified increased EDLOS, particularly for patients requiring admission. Mapping of 382 patient journeys identified delays in time to triage assessment (0–39 mins) and extended waiting room stays (0–348 mins). High proportions of patients received care outside ED cubicles. Four qualitative themes emerged: coping under pressure, compromising care and safety, makeshift spaces, and makeshift roles. Three key findings emerged: i) hidden waits such as extended triage-queuing occur during the input phase; ii) makeshift spaces are frequently used to assess and treat patients during times of crowding; and iii) access block has an adverse effect on output flow. Data suggests arrival numbers may not be a key predictor of EDLOS. This research contributes to our understanding of ED crowding and patient flow, informing service delivery and planning.