USING COMPUTERIZED WORKFLOW SIMULATIONS TO ASSESS THE FEASIBILITY OF WHOLE SLIDE IMAGING: FULL ADOPTION IN A HIGH VOLUME HISTOLOGY LABORATORY David McClintock, M.D. Fellow, Pathology Informatics Massachusetts General Hospital IADP Conference August 4, 2011
WORKFLOW DEFINED Workflow is a depiction of a sequence of operations Can be declared as work of: A person A group of persons, An organization of staff One or more simple or complex mechanisms From: http://en.wikipedia.org/wiki/workflow last accessed 07/24/2011, image from: medical.siemens.com 2
ANATOMIC PATHOLOGY WORKFLOW: GENERAL OVERVIEW ACCESSIONING GROSSING / SPECIMEN PROCESSING HISTOLOGY CASE POST- PROCESSING & ARCHIVAL PATHOLOGIST REVIEW / CASE SIGN OUT CASE DISTRIBUTION 3
DOCUMENTING WORKFLOW Workflow model to represent real work for further assessment Describes a reliably repeatable sequence of operations Workflows can be documented with processes Workflow more general concept, refers to any systematic pattern of activity Processes more specific notion than workflow Well-defined inputs, outputs and purposes Adapted from: http://en.wikipedia.org/wiki/workflow last accessed 07/24/2011 4
GROSS ROOM PROCESS MAP 5
MAPPING PROCESSES MGH ANATOMIC PATHOLOGY Documented using Microsoft Visio 2007 Subject matter experts (SMEs) and laboratory technical directors Multiple sessions (May 2010 to October 2010) to flowchart all AP laboratory and administrative processes Thirty-seven (37) process maps created in seven primary work areas 6
APPLYING BUSINESS TOOLS TO PATHOLOGY Business process analysis software igrafx Process (Corel Corp) Used to create virtual representations of the processes of an enterprise business For analysis and improvement Traditionally used for business divisions like: Manufacturing Purchasing Marketing Sales 7
APPLYING BUSINESS TOOLS TO PATHOLOGY Benefits: Can leverage experience of business and manufacturing processes for labs Transactions = specimens, blocks, slides, etc Resources = employees and instruments Compare time, resource efficiency, costs, etc. Focus is on generating data upon which to make decisions Simulations to assess potential changes made to documented workflow 8
SIMULATION PROJECT DESIGN Create igrafx workflow process maps Import Visio or directly create in igrafx Collect process step data from work areas Create computer-assisted process models from the acquired data Proc ess Ste Timin p Collection Perform on MethodCompletion g (range or consta nt time) 9
IGRAFX USER INTERFACE 10
COLLECTING THE DATA Good data is hard to find Best practice gather data from AP LIS At MGH current LIS could not provide data necessary to fill the models Problem not unique to MGH Observation data Observe process steps in action Act of observation changes the nature of the process Processes not as standardized as we thought Estimate data Best estimates from technicians and lab managers Ok for creating and testing models / simulations 11
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BUILDING PROCESS MODELS Generators: Introduce transactions into model Resources: Employees and equipment used in your model Each process step is assigned one or more resources Process Properties: Time to perform task constant, distributed, or expression Actions to perform on transactions batch, unbatch, etc 14
RUNNING SIMULATIONS 15
DATA GENERATION Reports generated from simulations: Time and queue data (by process, transaction, resource, etc.) Resource data (resource utilization, busy time, wait time, etc.) Cost data (total process cost, per resource, per transaction, etc.) 16
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WSI AND AP WORKFLOW QUESTION: Is full adoption of WSI feasible today (or in the near future) from a histology workflow perspective? How will adding a WSI robot to the Histology Laboratory affect the turn-around-time of slides getting to pathologists? How many WSI robots will be needed to maintain current workflow? How fast will slides need to be scanned to maintain the current workflow? 18
WSI FULL ADOPTION MODEL & SIMULATION Run the baseline Histology model: Without WSI robot With WSI robot With additional WSI robots (if necessary) With WSI robot at decreasing scanning times Primary data analysis Total simulation run time How long does it take to finish the day s work? 19
MODEL PARAMETERS Blocks generated (1200 blocks total) 4 processor batches Slides created (2400 total) 2 slides created for each block Resources: Determined from surveying the lab reflects current MGH Histology lab resources No breaks given to employees Histology schedule followed: 2:30AM to 8PM Rework not accounted for at this time 20
Basic Histology Model Blocks = 1200 Slides = 2400 No WSI Robot 21
Basic Histology Model Blocks = 1200 Slides = 2400 WSI Robot = 1 22
WSI DRASTICALLY INCREASES SLIDE TURN- AROUND-TIME WSI SCAN TIME: 60 180 sec WSI SCAN TIME: 60 240 sec WSI SCAN TIME: 90 180 sec WSI SCAN TIME: 120 240 sec 23
MANY WSI ROBOTS NEEDED FOR MINIMAL EFFECT ON TAT WSI SCAN TIME: 60 180 sec # WSI Robots Histology TAT WSI SCAN TIME: 90 180 sec WSI SCAN TIME: 60 240 sec WSI SCAN TIME: 120 240 sec 24
HOW FAST DOES A WSI HAVE TO BE? 12-13 sec / scan with 1 WSI robots 24-26 sec / scan with 2 WSI robots 36-39 sec / scan with 3 WSI robots 25
WSI WITH CURRENT WORKFLOW: FULL ADOPTION How will adding a WSI robot to the Histology Laboratory affect the turn-around-time of slides getting to pathologists? Increase TAT 10-fold to 20-fold (DAYS!!) How many WSI robots will be needed to maintain current workflow? 9 to 14 WSI robots How fast will slides need to be scanned to maintain the current workflow? 12-13 sec / scan with 1 WSI robot present 26
WSI WITH CURRENT WORKFLOW: FULL ADOPTION QUESTION: Is full adoption of WSI feasible today (or in the near future) from a histology workflow perspective? NO Workflow in AP Labs is not mature enough to support WSI 27
CONCLUSIONS WSI CANNOT BE IMPLEMENTED WITHOUT CHANGES IN WORKFLOW FIRST!! Cannot rely on WSI vendors alone to drive innovation Need proper assessment and data from our laboratories to drive full adoption of WSI Need to redesign AP workflow first before WSI can be accommodated 28
THANK YOU IADP Massachusetts General Hospital Dr. John Gilbertson Dr. Yukako Yagi Dr. Thomas Gudewicz Dr. Roy Lee 29