In healthcare the majority of quality issues stem not from individual errors but from systemic flaws that set the stage for failure. That may come as a surprise - and it requires a shift in how we think about quality. But as the late Dr. Lucian Leape, a pioneer in patient safety, famously stated:

In healthcare, a system is commonly defined as a coordinated network of people, processes, technologies, and settings that work together to deliver safe, effective, and patient-centered care. Systems issues often manifest themselves as latent safety threats: hidden problems in equipment, environment, processes, or communication that lie dormant until they contribute to harm.

In situ simulation, or simulation conducted in an actual care environment, has emerged as a powerful tool not only for training but also for uncovering these threats before they reach the patient. By recreating real-world clinical scenarios, in situ simulation allows teams to surface vulnerabilities that would otherwise go unnoticed. This provides a unique lens into the quality and reliability of healthcare delivery systems. 

The complex, high-pressure environment of the Emergency Department (ED) makes it especially vulnerable to latent safety threats (LSTs).³ Often referred to as “accidents waiting to happen,” LSTs are system issues that aren’t immediately apparent and can make it easier for healthcare providers to make errors. 

In this article, we explore how you can use in situ simulation to help uncover LSTs and drive quality improvement in your ED.

Why In Situ Simulation Is an Optimal Tool for Uncovering Latent Safety Threats in the ED 

In situ simulation gives you a unique opportunity to stress-test your system, because it takes place in the actual clinical setting.
 
Dr. Andrew Petrosoniak, MD, MSc (Med Ed), FRCPC, Emergency Physician and Trauma Team Leader at St. Michael’s Hospital in Toronto, Canada, compares in situ simulation to crash testing a car.⁵  
 
“You can imagine that no car company is ever going [to] roll out a car that hasn’t been crash tested,” he points out. “It's not sufficient to just drive it around the neighborhood and say that it’s safe. It needs to be put through a collision. In simulation, it’s the exact same process. We can replicate systems, processes, [and] we can study physical spaces much better using simulation and understand exactly how things will work before a patient ever arrives.” 

Read on to explore 4 common LSTs that EDs have uncovered and resolved using in situ simulation. 

1. Medication safety

In situ simulation scenarios allow providers to practice the entire process of medication administration, from prescription to dispensing to administration to the patient. 

Common medication LSTs that simulation has identified include: 

• Lack of fast/easy access to medications 
• Missing medications or concentrations
• Difficulty interpreting new labeling
• Difficulty with medication dose calculation 

The Pediatric ED at the Cincinnati Children’s Hospital Medical Center conducted 90 in situ simulations.⁷ They discovered 73 LSTs – and 30% of them were related to medication safety, including: 

• Critical medication was missing from their Pyxis™ MedStation™ System 
• There was a knowledge gap about available IV drips and how to obtain them 
• Similar-looking medications were being kept in the same drawer of their Pyxis™ MedStation™ System 

Another ED in Canada initiated an in situ simulation program to identify LSTs as part of a quality improvement project.⁸ Through the simulations, they found 158 LSTs – with medication issues accounting for 1 in 5 of them. LSTs included:

• Medication cart was too far from the room, and there was difficulty locating medications and supplies within it
• Missing medications or concentrations
• Difficulty calculating pediatric medications during resuscitation 

2. Equipment issues 

Equipment is often a proximate cause. A 2024 literature review on in situ simulation in emergency medicine found that 83% of the LSTs identified were related to equipment issues.⁹  

We already mentioned critical medications missing from Pyxis machines. Add to that potential unfamiliarity with electrocardiogram (ECG) machines, multiparameter monitors, pulse oximeters, blood pressure monitors, portable X-ray machines, ultrasound, defibrillators and more. There is a lot for ED personnel to manage. 

One of the greatest benefits of in situ simulation is that it allows you to use your own equipment. In doing this, many hospitals have found issues with:

In one study consisting of 18 in situ simulations performed across 11 EDs, participants uncovered a total of 158 LSTs - 25% of which were related to equipment,¹⁰ including:

Simulations can also be tailored to specifically include medical equipment malfunctions. This allows providers to practice their response to such situations, identifying LSTs related to equipment reliability, maintenance issues, and potential consequences for patient care. 

3. Protocol inefficiencies 

Dr. Andrew Petrosoniak shared how his hospital used simulation to drastically improve their massive transfusion protocol in the ED.¹¹ By simulating the protocol in the actual environment of the ED, he and his staff uncovered issues including: 

To mitigate the issues found, they streamlined their process to order blood and educated the porters on the crucial nature of receiving blood rapidly for a trauma patient. When they later measured how their protocol adjustments were translating to actual patient care, they found some amazing results: 

This example illustrates that utilizing simulation to expose and improve systems issues like inadequate protocols can make a substantial impact on patient care. 

4. Teamwork and communication factors 

In a complex and high-stress environment like the ED, strong teamwork, especially interprofessional teamwork, is critical.¹³ In situ simulation provides a risk-free environment to bring everyone together to practice as a practice as a team in the same space they work in daily. A well-designed simulation scenario followed by a thorough debriefing can identify LSTs related to miscommunication, misunderstandings, or breakdowns in communication among different members of the healthcare team. 

When you think about the types of scenarios in which solid teamwork is of the utmost importance, codes may come to mind. One study used in situ simulation to study resuscitations in the trauma bay of the ED.¹⁵ They used a SimMan 3G simulator and recorded all the scenarios to facilitate careful debriefing and review.  

They uncovered 843 LSTs during 12 simulations.¹⁶ Fifty percent of them involved teamwork and communication, and many of the LSTs were categorized as critical threats. 

LSTs included: 

• Lack of closed-loop communication
• Uncertainty about status of outstanding orders or actions
• Lack of role clarity among team members
• Patient care activities delayed or not completed due to task overload
• Shared mental models not established