Application of Queuing Analytic Theory to Decrease Waiting Times in Emergency Department: Does it Make Sense?

Abstract

BackgroundPatients who receive care in an emergency department (ED), are usually unattended while waiting in queues.ObjectivesThis study was done to determine, whether the application of queuing theory analysis might shorten the waiting times of patients admitted to emergency wards.Patients and MethodsThis was an operational study to use queuing theory analysis in the ED. In the first phase, a field study was conducted to delineate the performance of the ED and enter the data obtained into simulator software. In the second phase, "ARENA" software was used for modeling, analysis, creating a simulation and improving the movement of patients in the ED. Validity of the model was confirmed through comparison of the results with the real data using the same instrument. The third phase of the study concerned modeling in order to assess the effect of various operational strategies, on the queue waiting time of patients who were receiving care in the ED.ResultsIn the first phase, it was shown that 47.7% of the 3000 patient records were cases referred for trauma treatment, and the remaining 52.3% were referred for non-trauma services. A total of 56% of the cases were male and 44% female. Maximum input was 4.5 patients per hour and the minimum input was 0.5 per hour. The average length of stay for patients in the trauma section was three hours, while for the non-trauma section it was four hours. In the second phase, modeling was tested with common scenarios. In the third phase, the scenario with the addition of one or more senior emergency resident(s) on each shift resulted in a decreased length of stay from 4 to 3.75 hours. Moreover, the addition of one bed to the Intensive Care Unit (ICU) and/or Critical Care Unit (CCU) in the study hospital, reduced the occupancy rate of the nursing service from 76% to 67%. By adding another clerk to take electrocardiograms (ECG) in the ED, the average time from a request to performing the procedure is reduced from 26 to 18 minutes. Furthermore, the addition of 50% more staff to the laboratory and specialist consultations led to a 90 minute reduction in the length of stay. It was also shown that earlier consultations had no effect on the length of stay.ConclusionsApplication of queuing theory analysis can improve movement and reduce the waiting times of patients in bottlenecks within the ED throughput.

Operations research/management contributions to emergency department patient flow optimization: Review and research prospects

“…Gallivan et al (2002) simplify the patient flow process through a heavy-traffic deterministic system, assuming that the number of patients per day, the probability of "success," and patient LOS is always the same. For some other studies regarding applications of queueing theory in the ED, we refer interested readers to Alavi-Moghaddam et al (2012) and the references therein.…”

A Conceptual Framework for Improving Critical Care Patient Flow and Bed Use

“…leadership to better understand patient throughput and improve bed availability (36)(37)(38). Our model was informed by the current admission process at one institution but could be readily adapted to other locations with adjustments of empiric inputs and bed assignment algorithm.…”

Analysis of Factors Related to Length of Stay Time in Patients with Back Pain at Emergency Department

“…Several studies have sought to find causes and solutions of the overcrowding for the right function of emergency room (ER), but they have not been able to provide clear methods and have reported that efforts at the national level are necessary for the issue to be solved [1]. As a solution to the overcrowding, there is also a report that the shortening of patients' stay time has been achieved through the analysis of the treatment process [2].…”