Redesigning emergency department patient flows: application of Lean Thinking to health care.

Objective: To describe in some detail the methods used and outcome of an application of concepts from Lean Thinking in establishing streams for patient flows in a teaching general hospital ED.

Methods: Detailed understanding was gained through process mapping with staff followed by the identification of value streams (those patients likely to be discharged from the ED, those who were likely to be admitted) and the implementation of a process of seeing those patients that minimized complex queuing in the ED.

Results: Streaming had a significant impact on waiting times and total durations of stay in the ED. There was a general flattening of the waiting time across all groups. A slight increase in wait for Triage categories 2 and 3 patients was offset by reductions in wait for Triage category 4 patients. All groups of patients spent significantly less overall time in the department and the average number of patients in the ED at any time decreased. There was a significant reduction in number of patients who do not wait and a slight decrease in access block.

Conclusions: The streaming of patients into groups of patients cared for by a specific team of doctors and nurses, and the minimizing of complex queues in this ED by altering the practices in relation to the function of the Australasian Triage Scale improved patient flow, thereby decreasing potential for overcrowding.