Secondary Logo

Institutional members access full text with Ovid®

Share this article on:

Using Computer Simulation to Study Nurse-to-Patient Ratios in an Emergency Department

Henneman, Philip L. MD; Shin, Seung Yeob MS; Brun, Yuriy PhD; Balasubramanian, Hari PhD; Blank, Fidela MN, MBA, RN; Osterweil, Leon J. PhD

JONA: The Journal of Nursing Administration: November 2015 - Volume 45 - Issue 11 - p 551–556
doi: 10.1097/NNA.0000000000000262

OBJECTIVE: To study the impact of nurse-to-patient ratios on patient length of stay (LOS) in computer simulations of emergency department (ED) care.

METHODS: Multiple 24-hour computer simulations of emergency care were used to evaluate the impact of different minimum nurse-to-patient ratios related to ED LOS, which is composed of wait (arrival to bed placement) and bedtime (bed placement to leave bed).

RESULTS: Increasing the number of patients per nurse resulted in increased ED LOS. Mean bedtimes in minutes were impacted by nurse-to-patient ratios.

CONCLUSIONS: In computer simulation of ED care, increasing the number of patients per nurse resulted in increasing delays in care (ie, increasing bedtime).

Author Affiliations: Professor and Attending Physician (Dr Henneman) and Assistant Professor and Nurse Research Coordinator (Ms Blank), Department of Emergency Medicine at Tufts University School of Medicine, Baystate Medical Center, Springfield, Massachusetts; PhD Candidate (Mr Shin) and Assistant Professor (Dr Brun), School of Computer Science, and Associate Professor (Dr Balasubramanian), College of Engineering, University of Massachusetts, Amherst; and Professor (Dr Osterweil), School of Computer Science, University of Massachusetts, Amherst.

This research was partially supported by the US National Science Foundation under awards IIS-1239334 and CNS-1258588 and the National Institute of Standards and Technology under grant 60NANB13D165.

The authors declare no conflicts of interest.

Correspondence: Dr Henneman, 109 Lake Ave, Sunapee, NH 03782 (

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (

Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.