- Ontario, Canada
- Evaluate the needs of step-down beds to maximize ICU patient throughput, deliver efficiency and minimize cost
Achievements with Simul8
Projected $10 million of potential cost savings over span of 8 years
Identified average bed utilization rates based on multiple scenarios
Established evidence in reducing length of stay by up to 100 hours per patient
Gathered detailed evidence to reinforce decision-making using simulation
About the project
London Health Sciences Centre and Ivey Business School utilized Simul8 healthcare simulation software to evaluate the implementation of ‘step-down’ or 'level 2' beds, identifying positive impacts on ICU patient throughput, length of stay and costs.
In congested hospitals it can be common for patients to overstay at Intensive Care Units (ICU) due to blockages and imbalances in capacity. There are various reasons why an unnecessary stay in the ICU can be costly for hospitals:
- Clinically - patients occupy a service they no longer need
- Operationally - it disrupts flow from upstream units
- Financially - ICU beds are more expensive than ward beds
To meet this challenge, step-down beds (also known as level 2 beds) are an increasingly popular and less expensive alternative to ICU beds.
London Health Sciences Centre (LHSC), one of Canada’s largest acute-care teaching hospitals, together with the team at Ivey Business School for Health Innovation, utilized simulation to identify the impact of using step-down beds in the University Hospital’s Medical Surgical Intensive Care Unit (MSICU).
Analyzing historic data, it was identified that of patients treated in the ICU in 2014, 660 out of 864 were recorded with a NEM score (a measure of nursing workload requirements) that would have enabled those patients to eventually step down into a level 2 ward - saving valuable potential resources. The key goal of LHSC’s research was to evaluate if additional ICU bed capacity could be released through the use of level 2 beds and how many beds would be needed to deliver efficiency and cost savings.
The team also wanted to assess whether NEM scoring could be used to identify when a patient could be stepped-down and help estimate level 2 bed needs. Using Simul8, the team could consider a wide range of parameters to fully assess the impact on patient flow, length of stay, utilization and costs - all within a safe, risk-free environment.
"With many complex processes and parameters involved, we needed simulation to be able to test the implementation of step-down beds to meet our objectives of maximizing patient throughput, while minimizing the length of stay in the ICU and cost to the hospital."
Ivey International Centre for Health Innovation
Key project steps
Utilizing existing data to create step-down rules
The team were able to utilize existing data from LHSC’s patient management system, containing patient arrival times and characteristics, as well as precise patient transfer files.
This provided a view of the individual beds where the patients came to and from in each hospital unit. Additionally, as nursing workloads are recorded at upon arrival and once daily, as well as when the patient leaves the unit, the team had access to data on the NEM scoring process for every patient that went into the MSICU.
Distributions could then be created, along with a patient flow matrix and step-down rules to power the simulation.
Planning the simulation
To take into account the various entry points and congestion that occurs in the hospital, and assess how these complexities could potentially impact the use of level 2 beds, the team made the decision to simulate the entirety of the hospital patient flow.
The simulation also included stochastic attributes, such as the probability of death, to give a fully accurate representation of what really happens in the ICU.
Validation and testing step-down bed scenarios
After validating the accuracy of the base simulation against the current system performance, the team could run different scenarios to identify the best approach to the implementation of level 2 beds:Scenario one
Adding up to 20 beds in a new level 2/step-down unit, with no changes to existing MSICU beds.Scenario two
Re-allocation of existing capacity by converting some of the 25 MSICU beds into level 2 beds.Scenario three
Adding 5 extra beds to bring total MSICU capacity to 30 beds, allocating these between the MSICU and a new level 2 unit.
"The results from the simulation were very helpful and provided additional evidence to reinforce our decision-making. It has been a very useful project to be involved with on a very relevant question."
London Health Sciences Centre
Reducing MSICU length of stay
The simulation showed that as the number of level 2 beds increased, patient length of stay could also drop dramatically.
From the baseline of 160 hours per patient, in the beginning there is a sharp increase. As patient flow into the level 2 unit improves, there would be a sharp drop – eventually reaching a threshold of roughly 60 hours. In the scenarios where beds are reallocated from existing capacity, the level 2 unit would eventually become bottlenecked by the MSICU, with length of stay starting to increase again from this point.
Reducing patient length of stay by up to 100 hours per patient would provide substantial extra capacity as ICU beds are released to receive new patients that emerge from the operating room.
Achievements with Simul8
Using Simul8, LHSC could quickly run each of the scenarios and get detailed results around the key metrics of cost, length of stay and utilization of the MSICU and level 2 beds.
Across all scenarios, it was found that simulating level 2 beds into the current patient flow generally provided a positive impact - reducing occupancy, decreasing length of stay of MSICU patients, as well as saving and costs. Comparing the three different scenarios to the baseline results, it was found that converting existing capacity from the MSICU would provide an optimal balance on return, rather than adding new, additional capacity.
Adding the NEM scoring process and the stochastic death probability process into the simulation proved to also be very useful, helping identify the point where patients could be stepped down from an ICU bed to a level 2 bed. With the project delivering many valuable insights, LHSC are now looking at using simulation in their sister hospital, Victoria Hospital, as well as creating simulations to look at the impact of having dedicated long-stay beds.