Investment in Lean Lab Implementation Promotes Efficiency for Nationally Ranked Hospital

Children's National Medical Center, Washington, DC
Perspective by Joseph Campos, Ph.D.
Director of Microbiology and Molecular Diagnostics Laboratories

Summary Results:

  • Reallocated current staffing to enable three shift coverage Monday-Friday and two shift coverage weekends and holidays
  • Eliminated almost all workload-related overtime spending
  • Decreased average positive blood culture TAT by as much as 27 hours
  • Dramatically improved utilization of microbiology laboratory space
  • Physician & Staff satisfaction has increased significantly

Lean Lab Design is a service, offered by bioMérieux , applies Lean/Six Sigma principles to the microbiology lab. This service involves 3-5 days of observing the lab at its current state - the physical layout and the manner in which samples are processed. The deliverable is a roadmap outlining how the lab can improve processes to reduce waste and improve efficiency, while simultaneously increasing the quality of results and reducing errors. In 2009, The Children's National Medical Center (CNMC) partnered with bioMérieux to apply the Lean/Six Sigma process to the hospital's microbiology lab. Three years later, the results on workflow, turnaround times (TATS), and patient outcomes have been dramatic.

About Children's National Medical Center

Children's National Medical Center (CNMC) is the only exclusive provider of pediatric care in the metropolitan Washington DC area. Nationally recognized as one of the best pediatric hospitals in America by US News & World Report and the Leapfrog Group, Children's National has been serving the nation's children for more than 130 years and is a proven leader in the development and application of innovative new treatments for childhood illness and injury. The hospital cares for more than 360,000 patients each year who come from throughout the region, nation and world. Serving as an advocate for all children, Children's is the largest non-governmental provider of pediatric care in the District of Columbia, providing more than $50 million in uncompensated care. In addition, Children's serves as the regional referral center for pediatric emergency, trauma, cancer, cardiac and critical care as well as neonatology, orthopaedic surgery, neurology, and neurosurgery. Joseph Campos, Ph.D. is the Director of the Microbiology and Molecular Diagnostics Laboratories at CNMC.

What Is The Value To The Patient?

According to data collected by bioMérieux, the vast majority of process time in the average U.S. hospital microbiology laboratory is not spent on "core value" activities. On average, 5% of process time is spent on backlog requests, 23% on extra work performed because of missing information, 27% waiting to complete the next "core value" step due to unavailable staffing or equipment , 4% spent on unnecessary motion (e.g. walking to the suboptimal location of the next task), 12.5% spent on review and quality assurance, 7% spent on call or log information, and nearly 10% spent on correcting quality issues (identifying, handling and fixing defects in the process).

The Intangible Value Of The Microbiology Lab And How It Can Be Wasted

"Time spent on 'non-core value' activities is not always wasted time," said Dr. Campos. "Review and quality assurance activities, for example, are important. Our goal has been to increase the ratio of 'core value' to 'non-core value' time by eliminating the causes of problems that demand the expenditure of 'non-core value time' for their solutions. By not addressing the sources of these resource-wasters earlier, we found that we had institutionalized our own inefficiencies."

In the bioMérieux Lean Lab process, these inefficiencies are defined as waste - but not in the traditional sense.

"In the bioMérieux approach, waste actually refers not to unused or misused physical material but rather to the true value proposition offered by the microbiology laboratory: its expertise, time, and capital," said Anne Beal , Manager Workflow Optimization Team of bioMérieux. "That's the real treasure of the microbiology laboratory. It's not a tangible thing, but the relationship of the laboratory as a resource and the members of the laboratory staff. This is not the kind of waste that ends up in a garbage can, but it is in a very real sense a missed opportunity to improve the core value of the microbiology laboratory."

This waste includes work not performed because of staff unavailability, rework to correct avoidable mistakes, excess motion due to an ill-designed floor plan, and excess work caused by inefficient test procedures.

For example, Graph 1 illustrates "waste" caused by laboratory staffing not being aligned with testing demand. This analysis was part of the "Kaizen Approach" used by bioMerieux to review the CNMC microbiology lab workflow.

Children's National Medical Lean Lab Case Study - Microbiology Pathway

Graph 1: Hourly Volume and Specimen Process Staff Capacity Distribution

Post-LEAN Staffing: Minimizing the Extreme Peaks and Valleys

Prior to the LEAN laboratory assessment, the microbiology laboratory at CNMC employed 11 FTEs and it still does. Due to increased efficiency, the staff productivity has dramatically improved, which can be measured by the increased number of tests per person-hour and reduced turn-around times.

"From a financial perspective, it's fair to say that the productivity of the laboratory today would have required another FTE under the pre-LEAN scenario," said Dr. Campos.

Prior to the bioMérieux Lean Lab Assessment, CNMC was essentially a day-shift laboratory, from 7:30 am to 4 pm, with almost the entire staff working the same shift. As a result, the day shift began each morning with a backlog of new specimens and positive blood cultures from the previous night that needed to be processed. One of the most effective changes made as a result of our LEAN assessment was to convert our microbiology laboratory to a 24-hour operation, Monday through Friday. By staffing both a night shift (11:30 pm to 8:00 am), and an evening shift (3:30 pm to midnight) with two technologists, the day shift (7:30 am to 4:00 pm) arrives each morning to find the workload from the night shift has already been completed.

And, since that 8.5-hour day shift window often wasn't sufficient to complete the work, the pre-LEAN laboratory required a great deal of overtime. Those overtime hours have been largely eliminated.

With four FTEs working the evening and night shifts, the laboratory is constantly processing new specimens and examining new cultures , rather than compressing all of this critical work into a single work shift. Positive cultures are now identified and worked up during the evening hours or even in the middle of the night, and those results are made available to physicians immediately, rather than waiting until the next day shift.

But a reallocation of 11 FTEs was just one step in our LEAN process. By distributing workload and staff to the evening and night shifts, we made it possible to move automated molecular testing from our day shift only Molecular Diagnostics laboratory to the Microbiology laboratory so that this testing is now performed STAT rather than in batch mode. The improved TAT for automated molecular testing has been dramatic, as seen in Table 2.

In the pre-LEAN laboratory, all culture plate reading occurred during the day shift only. If growth was insufficient to permit culture workup, the culture media were placed back into the incubator for another 24 hours. Now, our cultures are examined for the first time after 16 hours of incubation, regardless of the time of day. If growth is insufficient for culture workup, the culture media are re-incubated for four hours and checked again.

"Very often, 16 hours of incubation is enough time to obtain adequate growth to inoculate identification and antimicrobial susceptibility tests. In our pre-LEAN laboratory, inoculation of identification and susceptibility tests from uncomplicated cultures often occurred 24-48 hours after specimen receipt. Currently it now happens as quickly as 16 hours and almost always in less than 24 hours," said Dr. Campos.

Redesign Focusing On Core Value Improvement

One of the other major changes resulting from the LEAN Laboratory assessment was the redesign of the laboratory floor space in order to create a Microbiology Incoming "work cell", or a work area dedicated to the very complex and iterative process of receiving and processing new specimens.

"Prior to the redesign, our laboratory's Incoming area was a major thoroughfare so you can imagine the chaos created with hundreds of daily walk-throughs in an area where our laboratory scientists needed to be very focused," said Dr. Campos. "This was a vital change and I can't overestimate the value of its implementation. We basically moved our Incoming area into the main Microbiology Laboratory where pass-through traffic is much reduced." Furthermore, Microbiology Incoming is now much closer to our media storage and our incubators resulting in much less nonproductive walking.

Freeing Up Much Needed Lab Floor Space For Automation

With fewer staff now on our day shift, the microbiology laboratory actually needs much less bench space so the lab was able to eliminate two of four culture plate reading areas. More floor space was recovered by instituting twice weekly instead of once weekly culture media shipments. Some of the "new" floor space was used to house a newly acquired bioMérieux PREVI™ Isola automated plate streaking system. Not only does this award-winning device free up well-trained lab scientists from the chore of manually streaking culture plates, PREVI Isola has demonstrated that it provides better colony isolation, leading to fewer subculture plates during workups and faster identification and antimicrobial susceptibility testing.

The Ultimate Measure: Turn Around Times

Of course, all of the benefits described above conceptually are good, but that is not enough. A LEAN laboratory based on Kaizen principles must improve the core value of laboratory testing: i.e. faster and more accurate test results.

According to Dr. Campos, he compared the TATs from identical six month periods: November 2009 to April 2010 (Pre-LEAN) and November 2010 to April 2011 (Post-LEAN), first looking to see if the patient demographics, ages, and types of testing performed were comparable during these two time periods. He found that they were. He also did a day of the week comparison to see if the work flow was similar. Again, they were.

"We have seen a significant improvement in TATs for positive cultures from all specimen types: blood, stool, urine and miscellaneous -- it's really quite remarkable ," said Campos. "We've gained, on average, a complete day in our positive culture TATs post-LEAN (See Table 1). This is most profound early in the work week. Since the LEAN staffing changes had to be limited to weekdays, we've seen no improvement in TAT on Saturday, and a slight improvement on Sundays".

Table 1: Days Of The Week: Pre And Post Lean Positive Culture TATs

Days Of The Week: Pre And Post Lean Positive Culture TATs - Pathway Case Study

Dr. Campos analyzed the TAT improvements for patients in the critical care departments, which was one of the primary motivations for undergoing the LEAN assessment process because -- for obvious reasons -- getting results to critical care doctors as quickly as possible is vitally important. . Table 2 Illustrates the improved TATs for positive cultures from critical care department patients, while Table 3 shows the shorter TATs for positive blood culture from specimen collection to susceptibility reporting by organism. Table 4 reveals the improvements in TATs based on time of day and, lastly, Table 5 ranks the improved TATs by organism.

Table 2: Critical Care TAT Improvements by Department

Critical Care TAT Improvements by Department - Pathway Case Study

Table 3: TAT Improvements from Positive Blood Cultures to Antibiotic Susceptibility Report to Physicians by Bacteria

TAT Improvements from Positive Blood Cultures - Pathway Case Study

Table 4: TATs Pre- and Post-LEAN by Specimen Collection Work Shift

TATs Pre- and Post-LEAN by Specimen Collection Work Shift - Pathway Case Study

Table 5: Greatest TAT Improvements by Organism Ranked 1-7

TAT Improvements by Organism - Pathway Case Study