Value Stream Mapping (VSM) is often touted as an essential tool in applying Lean and seems like a natural fit for healthcare. VSM can show patient and information flow on a single sheet of paper along with resources, process times, delays, and other problems making it a useful tool in planning and communicating improvement activities in a seemingly simple format. Then why is VSM so frustrating to apply in some areas in health care?
It may be that sometimes VSM is the right tool for the wrong situation. The lean consulting and resource website, Strategosinc.com, points out that VSM was developed to map material and information flow in the automotive industry. Automobile plants are highly focused factories with a narrow family of products and few customers. Certainly there are high-volume linear production processes in healthcare. But while VSM works well for highlighting flow problems in this type of environment, the website counters that in high-variety, low-volume operations VSM is “cumbersome and unrealistic”. So VSM may not be the be-all and do-all tool that some would like us to believe.
So what do we use in these high-variety and low-volume operations? The Strategosinc.com website suggests we first classify our operations with Group Technology (GT). GT is frequently used in job shops that are characterized by high-variety and medium-to-low volume production within a defined range of product types. GT is based on a general principle that many products are similar and by grouping similar products, a single solution can be realized resulting in saving time and effort. Using production flow analysis (see the website again for an example of this) these groupings or families can be identified in order to arrange properly sequenced flexible manufacturing cells.
An example where GT might be applied in health care is in the emergency department (ED). Patients are generally triaged (grouped) prior to treatment so that care is sequenced and resources assigned appropriately. Many EDs have a Fast Track area where patients needing few resources are quickly examined, treated, and released; while the rest of the patients flow through the Main ED. Some have found that there are really three or four groups or families of patients in the ED. So beyond Fast Track, there might be two or more additional work cells that can be devised for more efficient and uniform flow.
Another limitation that Strategos points out is that while VSMs are effective for showing problems, they don’t provide enough resolution needed for detailed problem solving. The type of process map Strategos recommends is the same developed by Frank Gilbreth in the early 1900’s. Descriptive characteristics borrowed from VSM can be added to process maps to show value or non-value added steps, cycle time, inventory levels, yield, and staffing and equipment requirements. There are no shortcuts to get to the detailed process level, but the hard work pays off when your team can describe and analyze specific problems and solutions.
Don’t give up on VSM. It certainly has its place in health care. But for certain areas in your organization GT concepts and detailed process mapping may be a better tool.