Re-enginnering the ER

Systems scientists and industrial engineers harness the power of simulation to model better healthcare


By Natalie Blando-George

Soon after Mohamed El-Sharo, MA ’09, PhD ’12, graduated in May with a doctorate in industrial and systems engineering from the Watson School, he left for Minnesota to start his career at the Mayo Clinic. He is among the hundreds of engineering graduates nationwide who are using their expertise in process and system improvement to make hospitals, HMOs, long-term care facilities, clinics and other healthcare-related organizations more efficient and effective.

“As a health-systems consultant, I am providing technical advice to the hospital departments and units to improve their performance,” says El-Sharo, who was advised during his doctoral studies by Mohammad Khasawneh and Sang Won Yoon, faculty members in the Department of Systems Science and Industrial Engineering (SSIE). “I chose the Mayo Clinic because it is one of the leading healthcare organizations in the world.”

Discrete-event simulation (DES) is among the many engineering tools El-Sharo is using to help the Mayo Clinic streamline its operations.
According to Sarah Lam, associate professor of SSIE, “Discrete-event simulation is a technique that enables the user to evaluate the efficiency of existing healthcare delivery systems, to ask ‘what if’ questions and to design new systems.”

DES can be used to predict the impact of changes in patient flow, to examine resource needs or to investigate complex relationships among different variables (such as rate of arrivals or service). This data enables healthcare managers to select alternatives that can be used to reconfigure existing systems, improve system performance or design, or plan new systems. “A simulation study allows you to test different scenarios, make mistakes and try new things without impacting patients or staff,” Lam explains. “That’s not always feasible in the real world.”

One of the greatest advantages of DES, Lam says, “is its ability to capture the randomness found in the real world.” Simulation studies can provide results in minutes or hours rather than months or years, and they enable organizations to assess various options without committing precious resources to them.

Mohamed El-SharoMohamed El-Sharo, MA ’09, PhD ’12, is applying his expertise in process and systems engineering to departments and units at the Mayo Clinic.


“With simulation, there is no need to interrupt processes or stop them to experiment with improvement suggestions,” El-Sharo adds. “Because healthcare processes are very sensitive and directly involve patient safety, simulation seems to be the best tool to analyze those sensitive processes.”

Watson School students learn DES in Lam’s undergraduate- and graduate-level simulation courses. All students taking these courses must complete a simulation project, through which they implement the steps involved in developing a simulation study and learn how to model the various systems in simulation software, including Arena and Simio.

Most simulation software has animation capability. SSIE Assistant Professor Sang Won Yoon says that is useful in helping healthcare personnel, who typically don’t have an engineering background, visualize different scenarios. “We can show them how their current system looks and then how it would look if they implemented a process change,” he notes. “It’s much easier for people to understand than a lot of jargon and statistics.”

Through the Watson Institute for Systems Excellence (WISE), Lam, Yoon and SSIE Associate Professor Mohammad Khasawneh work with students on projects for healthcare organizations with an eye toward improving efficiency, reducing costs and increasing patient satisfaction and safety. Previous studies that used DES have focused on streamlining hospital emergency department patient and process flow, increasing the use of a hospital’s dental clinic, optimizing chemotherapy chair usage at an ambulatory infusion center and reducing wait time within a hospital’s outpatient physical therapy department.

In addition to discrete-event simulation, researchers in SSIE use digital-human modeling and agent-based simulation methods. “Depending on the nature of the behavior of the people or the nature of the processes that take place, we have to decide what type of simulation to use,” Khasawneh says. “The nature of the system being studied determines the type of simulation that’s most appropriate for the specific objectives identified for maximum impact.”

Digital-human modeling enables the user to simulate various work environments with biomechanically accurate “human” models and then measure the effects of different activities on the body. Khasawneh explains that you can determine the impact of various changes that can be made within the workplace to determine which will produce the most positive outcome on the human body from an ergonomics perspective.

“The ability to perform digital-human modeling is important, since doing these assessments in real life is difficult, time consuming, inconvenient and costly,” Khasawneh says. “By doing this in a simulated environment with biomechanically accurate digital humans, we can quickly and easily test different kinds of ‘what if’ scenarios.”

Previous healthcare-related research projects that used digital-human modeling examined patient lifting protocols, the stresses sonographers endure during ultrasound procedures and the appropriate height for an operating room table for surgeons performing laparoscopic procedures. “Studies like these help improve workplace safety and productivity,” Khasawneh says. “They can also be used to reduce the risks associated with work-related musculoskeletal disorders (WMSDs), such as back injury and upper extremity disorders.”

With agent-based simulation, every simulated person is considered an “agent,” and that agent’s actions and interactions are studied. Agent-based simulation is currently being used to evaluate why people in rural areas sometimes bypass their local hospital to seek services in a larger city, even when those services are available locally — an issue that has a significant financial impact on the local hospital.

As healthcare costs continue to rise, healthcare organizations are under pressure to improve efficiencies, reduce costs and increase patient satisfaction. With its proven record of helping them do just that, simulation continues to be an invaluable tool in the healthcare field, and those skilled at its use remain in high demand. Just ask El-Sharo.

“Being proficient in using simulation modeling as a tool, I built an impressive résumé that helped me get job offers from many healthcare organizations,”
he says. “This eventually led me to the Mayo Clinic.”

Watson Review Masthead