Instrument Set Flow in the Lean OR

The Lean OR, or in more inclusive terms the Lean Perioperative Services Department, can turn instrument sets quickly and with perfect quality. This may sound like a fairy tale to many of you, so let us first define what "quickly" means. To turn instrument sets quickly means that the lead time for a given instrument set must be as close as possible to the time it actually takes to decontaminate, wash, reassemble, wrap, and sterilize the instruments. We refer to this as the ability to "flow" instrument sets.

Let's assume a very simple sequence of processes from the time an OR surgical case is finished to the moment the instrument set is ready to be picked for the next case:

Spray -> Transport -> Decontaminate -> Wash -> Cool -> Reassemble -> Wrap -> Sterilize -> Store

Each of the steps above is what in lean terms we call a "process". The sequence of all processes to deliver a unit of value to a customer is called a Value Stream. There are three major stages in developing a lean value stream capable of flowing instrument sets:

• Calculate resources and design the physical layout
• Bring live and manage the value stream
• Sustain the changes

To fully design a value stream capable of flowing instrument sets in the fastest possible manner we must:

• Define the Product. The product is the individual instrument set. Since there are many variations, we recommend classifying them into groupings by specialty and size. To keep things manageable, use Large-Medium-Small. The amount of work content is directly related to the size of the set.

• Gather Volumes. Not all instrument sets are used equally. If your hospital is performs many Ortho surgeries, your knee sets and ortho minor surgical sets will get a lot of usage, while your cysto sets may rarely see the light of the OR suite. You will have to figure out how to get this usage data. If you have an instrument tracking system, that should be your first stop. If you trust your EMR's intra-operative notes, look at them. There is always the possibility to have to gather the data manually. We have done this and it is not that difficult. The goal is to have a figure of daily usage per instrument set.

• Define the Work. This is achieved by drawing a Process Flow Diagram (PFD) per instrument set. A PFD show the sequence of processes an instrument set follows. Patterns will start to emerge from this. The machine-washed sets that are wrapped follow a different processing path than the hand-washed peel-packed instruments. We are likely to end with a dozen different PFDs to cover all instrument sets.

• Identify Families. We must now analyze the PFDs and find groups of sets that share a common processing path. There may be two or three PFDs that are very close. These families of sets will give us the first indication of what physical processes should be collocated to minimize travel distances. This is normally achieved by creating a "Set-to-Process matrix". Picture a matrix with all instrument sets (or groups) as rows and all processes as columns. Every time a set goes through a process, place an "X" at the intersection.

• Gather Standard Times Per Process. This is probably your most laborious step. Go back to the prior step. Everywhere you see an "X" in the matrix, it must be replaced with the time it take to do the work in that process for that set. There may be some repetition and you might be able to use estimates, but it is a very good idea to reach for the stop-watch.

• Calculate Resources. The resource calculations are remarkably simple, yet they require a great deal of experience to interpret. The calculation is as follows:
Resources = Standard Time / Takt
Takt = Work time / Volume

• Develop a Conceptual Layout. This layout is your first pass to locate resources (people, machines, and inventory) in a block layout without any regard to the existing constraints. This is a highly recommended exercise, as it will give you a glance into the possibilities of an "ideal" layout.

• Develop the Actual Layout. Working on the blueprint of the available area and the picture of the conceptual layout, place all the resources in physical locations that most closely resemble the conceptual layout.

You now have the blueprint of your new department. You now must develop a plan to move all the resources, train staff in the new way of flowing sets, and begin the acquisition process of any new equipment you may need. A note on new equipment: resist your urge to buy stuff. Do all you can to redesign your department with the existing resources. A good redesign will not require any more capital equipment than what you have.

The next stage of your project is to bring live the department and manage the new instrument set flow. The live process must be done with the assistance of the entire process improvement team and the performance of the department must be closely monitored. You should plan to hit your stride within a few days. Keep a close eye on the expected performance as compared to actual performance and act swiftly if necessary. If the calculations show that the department should be able to flow a set in 160 minutes and you are not hitting this average response time within 3-to-5 days, you must take action. This may be a case of faulty assumptions, or an unexpected glut of hard cases that use large sets. Whatever the case, you cannot afford to wait and see.

To ensure the sustainability of results, you have to set up four key elements of a Lean Value Stream:

• Standard Work for Leaders. The idea behind this sustainability feature is that Standard Work applies to all in a Lean Value Stream. The closer we are to the value (the instrument set) the more standardized our work is. As an example, for a SPD the team established an "end-of-day checklist" for the department manager. This list had to be completed and signed off at the end of each day.

• Daily Accountability Process. This refers to setting up daily checkpoints, in the form of brief meetings, for all the team members in the department to ensure that all aspects of the value stream are being managed.

• Visual Controls. The Lean Value Stream moves fast, and it is very important to have the ability to check the status of the department by quickly scanning a series of visual controls. Examples are completion charts, statistical process control charts, and the instrument cooling rack (overflowing vs. empty).

• Discipline. This is what makes Lean work. Lead by example and allow no exceptions to the rules and the established processes. If there is a need for an exception, look for ways tostandardize the change.

This should give you a good starting point to get started with the Lean transformation in your Sterile Processing Department.

Gerard Leone, MSIE, MBA, is the Lean Hospital practice leader with the Leonardo Group Americas. The Leonardo Group is based in Munich, Germany and Denver, CO in the USA.
Gerard is has been a consultant to manufacturing companies for almost 20 years and to hospitals for 8 years. You can reach him at gleone@leonardo-group.com or visit the Lean Hospital Group website at http://www.leanhospitalgroup.com