emergency department overcrowding: developing emergency department capacity through process...

Abstract:Emergency department (ED) crowd-ing is a significant and growingpatient safety issue. Delays in theinpatient admission process are asignificant contributor to ED crowd-ing. We describe a systematic andcomprehensive effort to decreaseED length of stay using lean manu-facturing techniques derived fromthe Toyota Production System.Through a combination of projects,we describe how we were able tomeet a hospital goal to reduce thelength of time that admitted patientsremain in the ED.

Keywords:emergency service; overcrowding;length of stay; quality improvement;process assessment;process improvement

*Department of Pediatrics, University ofWashington School of Medicine,Emergency Services, Seattle Children'sHospital, Seattle, WA; †Department ofPediatrics, University of Washington Schoolof Medicine, Seattle Children's Hospital,Seattle, WA; ‡Emergency Department,Seattle Children's Hospital; §Division ofEmergency Medicine, University ofWashington School of Medicine,Emergency Services, Seattle Children'sHospital, Seattle, WA.Reprint requests and correspondence:George Woodward, MD, MBA, 4800 SandPoint Way NE, Seattle, WA 98155.E-mail: [email protected]

1522-8401/$ - see front matter© 2011 Elsevier Inc. All rights reserved.

ED OVERCROWDING: DEVELOPING ED C

EmergencyDepartment

Overcrowding:DevelopingEmergencyDepartmentCapacity

Through ProcessImprovement

APACITY THROUGH PROCESS IMPR

Russell Migita, MD*,Mark Del Beccaro, MD†,Dawn Cotter, RN, MBA‡,

George A. Woodward, MD, MBA§

mergency department (ED) crowding was recognized asa national crisis by the Institute of Medicine in their
E2006 report Hospital-Based Emergency Care: At the BreakingPoint.1 Since then, a great deal has been written about
the extent2-8 as well as the consequences9-20 of the problem.Traditional solutions proposed have included a mixture ofexpanding capacity and increasing speed. Expanding capacity

OVEMENT / MIGITA ET AL • VOL. 12, NO. 2 141

mailto:[email protected]

142 VOL. 12, NO. 2 • ED OVERCROWDING: DEVELOPING ED CAPACITY THROUGH PROCESS IMPROVEMENT / MIGITA ET AL

by building more ED rooms and/or increasing thenumber of providers is neither cost-effective norsustainable long-term solutions. Expecting staff towork faster when demand increases may increasethe risk for omissions, errors, and burnout.21

Seattle Children's Hospital and the Department ofPediatrics have embraced a cultural model ofcontinuous incremental change to improve thequality, safety, delivery, and cost of care for ourpatients by engaging all staff in these efforts. Ourcontinuous performance improvement (CPI) phi-losophy is derived from our study of the ToyotaProduction System (TPS). One of the key compo-nents of this system is recognizing and prioritizingthe value to the customer—in our case, the patientand family. To improve quality and value for ourpatients, we used CPI methodology to identify andremove the waste inherent in all systems and,specifically, in our processes.22,23 In this article, wewill describe one of the projects undertaken atSeattle Children's to illustrate the concepts of CPIand demonstrate how we were able to increase EDcapacity by decreasing the total length of stay (LOS)for our patients who were admitted to the hospital.

CONTINUOUS PROCESS IMPROVEMENTIN THE ED

A major process improvement initiative and agroup of related projects (labeled as “InpatientAccess Project”) were launched in 2008 in responseto overcrowding on the inpatient units. There wasagreement that acute improvement and a sustain-able response to expected continued growth in ourinpatient census would need to involve improve-ment in efficiency rather than a physical capacityincrease in the absolute number of beds. In 2009,the inpatient improvement process was expanded toinclude ED patients who were being admitted.Approximately half of the hospital's inpatientadmissions originated in the ED, and prolongedED-based care potentially impacted hospital LOSand overall quality of care. Prolonged ED stays maydelay access to providers and services for other EDpatients.24,25 Prolonged preadmission efforts in theED require a disproportionate amount of roomoccupancy and staff work and are a major factorassociated with ED crowding.5,26-28 Admitted pa-tients accounted for approximately 20% of the totalnumber of patients seen in our ED, but thispopulation's ED LOS was approximately twice aslong as that for discharged patients (median LOS forED admits 289 minutes vs 150 minutes fordischarges), and we recognized that improved

throughput could effectively increase ED capacity(Figure 1). This process improvement project alsoillustrates the multidisciplinary and interdepart-mental nature of our CPI work and the expansion ofvisioning and implementation beyond the walls ofthe ED. We believe that these are essentialcomponents for the success of ED CPI efforts.

This ED project had several subprojects toaddress the major cycles of an ED admission.Process mapping is a tool derived from the TPSthat systematically and visually displays each step ina process. This is developed through direct obser-vation of a process and captures who is responsiblefor each step, how long each step takes, and whethereach step adds value to the customer's experience.The following subprojects were picked based onprocess mapping that delineated the major andmeasurable events during the admission process:(1) decision to admit, (2) service assignment, (3)bed assignment, (4) readiness to admit, and finally(5) inpatient pull. A conscious decision was made toimprove every step of the admission process. Eachproject had owners responsible at the local level anda set of action plans and metrics that were trackedand regularly reported through the project teams tohospital senior leadership and in aggregate form tothe hospital board of directors. The metrics, actionplans, successes, and impediments were reviewedby senior leadership (sponsors), and as necessary,obstacles were addressed and mitigated. An impor-tant aspect of this project was that we did notestablish a goal to develop or determine specifictime targets for individual patients or diseaseprocesses, although a target aggregate time foradmission goal was set based on historical dataand expected improvement. Lessons from England'sNational Health Service ED admission mandateswere considered in the process of setting our goals.In 2005, in response to ED overcrowding, theNational Health Service mandated that 98% ofpatients be admitted within 4 hours of arrival,which led to concerns about shortcuts affectingpatient safety and staff morale.29,30 In contrast, wedid not focus on a specific target time, but rather onadding value and removing waste. Implicit in thisapproach is the fact that there is no set time to admitan individual patient—rather, the goal is to achievethe minimum possible time while still safelycompleting all value-added steps for the specificpatient and process. Achieving a short LOS is lessmeaningful and perhaps damaging if that admissionis ultimately unnecessary or if patient safety iscompromised in the process.

Continuous performance improvement conceptsemphasize standardization, the removal of waste,

Figure 1. Emergency department LOS for patients admitted to the inpatient units before (by fiscal year (FY) [October 1–September 30])and during/after admission process improvement efforts (by quarter for FY 2011). PDCA stands for “Plan, Do, Check, Act,” a key componentof all process improvement activities.

ED OVERCROWDING: DEVELOPING ED CAPACITY THROUGH PROCESS IMPROVEMENT / MIGITA ET AL • VOL. 12, NO. 2 143

and provision of value to the patient and theirfamily. Although a full discussion on the applicationof CPI/TPS principles to health care is beyond thescope of this article, these concepts embody someof the key principles of this approach. During theprocess mapping stage, each step in a process isobserved and measured. The steps are analyzed todetermine if they add value to the patient. Inmanufacturing, a value-added step would be onethat changes the form or function of a product, suchas the act of bolting an engine to a chassis. In healthcare, a comparable criterion would be a step thatthe customer would be willing to pay for. Althoughvalue may be interpreted in a variety of ways,examples of value-added steps include taking anx-ray image, receiving antibiotics for an infection,and discharge teaching. All other steps, such asqueuing, waiting for a provider evaluation or alaboratory result to come back, or being trans-ported to x-ray, are considered to be waste. In atypical process, 90% or more is waste. Althoughnot all non–value-added steps can be removed, thegoal of CPI is to relentlessly identify and eliminateunnecessary waste. Standardization helps achievethis goal by further identifying obstacles or non–value-added steps, reducing variability and reworkand by allowing the entire team to understand the

processes and move the patient forward to theirultimate goal.

ED ADMISSION PROCESSIMPROVEMENT PROJECTS

There are a number of different conceptualmodels of the ED process and ED flow.31-33 Wechose a model similar to that defined by Crane andNoon33 to serve as a framework for approaching ourimprovement efforts and to guide staff training(Figure 2). We chose to focus on 5 projects withidentifiable and measurable parameters. The time-line of the related projects are depicted in Figure 3.

Project 1: Decision to AdmitOne of the first priorities in process improvement

projects is to clearly define the area that is targetedfor improvement and ensure that metrics areavailable, measurable, and accurate. The timebetween first being seen by an independent providerand the cognitive decision to admit was targetedbecause it was often not as dependent on processesexternal to the ED. We also felt that being successfulat making decisions to admit as early as reasonablypossible would be associated with improved ED

Figure 2. Visual representation of ED admission process (the “5 D” approach) with 2011 goal noted. “DOT” is an acronym to help focus theteam on next steps needed, which stands for “Diagnostic tests, Observe until…, Treatments planned.”


communication and flow. A multidisciplinary groupof ED nurses and physicians met over 2 days to workon the project. The team was charged withexamining the current state, evaluating barriers toprogress, and charting a map toward an ideal state.Team members trialed several different interven-tions on their shifts over a 3-week period andassessed the effectiveness of the interventions. Thisallowed for rapid testing of small incrementalchanges, gathering feedback and metrics, andmoving to another improvement trial.

Seattle Children's uses a computerized orderentry and an electronic tracking board for EDpatients. Emergency department patient care datawere a part of the general hospital-wide clinicalinformation system. However, at the beginning ofthis project, we did not have a marker for thedecision to admit metric because this step repre-sented a cognitive event that was not always evidentto all staff caring for the patient. In an attempt tomake this process visual and to capture the time ofthe decision to admit, electronic icons were createdfor the tracking board. The first icon fired 60minutes after a patient was placed in a room. This

Figure 3. Project management grid for process improvement projecaccess projects.

visual icon served as a reminder for all ED staff toask whether enough information was available tomake a decision to admit and, if not, to define theplan to reach that point. A separate, manually firedicon was created to mark the actual decision point.Data were collected for each ED attending physi-cian, and the overall data were tracked andpresented to hospital leadership.

Project 2: Service AssignmentIn many cases, the decision to admit was not the

only step that was required to start the process ofadmitting a patient to the hospital. It may be clear toED staff that a toddler with a prolonged afebrileseizure or an infant with vomiting and diarrhea whohad a ventricular septal defect needed to beadmitted to the hospital, but there were no availablestandards directing decisions as to which servicethese patients should be admitted. Our system, atthat point, did not allow bed assignment untilattending service was identified, because cohortingof teams and disciplines were efficiencies deter-mined in previous (non-ED) process improvementefforts. Delays often stretched into hours as the ED

ts noting specific emphasis on individual and related inpatient

image of Figure 3

image of Figure 2


waited for multiple subspecialty conversations andconsultations to be completed in the ED before aservice could be definitively determined.

Leaders for the medical and surgical specialtyservices were asked to provide standardized inclu-sion and exclusion criteria for patients who may beconsidered for admission to their service. A docu-ment was developed to help ED staff make appro-priate decisions about service assignment.Agreement was reached so that ED staff, with theassistance of this standard work document, wouldhave authority to make initial service assignmentson behalf of each of the medical specialties. Beforeand after implementation, ED staff were surveyedfor ease of use of the tool and satisfaction with theservice assignment system. Specialty and housestaff were also surveyed. All groups showed in-creased satisfaction with the process.

Project 3: Bed RequestSeattle Children's had previously developed an

electronic admission bed request process throughour clinical information system. In March 2010, amultidisciplinary team of stakeholders participatedin a week-long rapid process improvement event toidentify opportunities to remove waste and reduceerrors and rework in the current system. Partici-

Figure 4. Bed request stan

pants in this event included parents, ED providers,clinic coordinators, residents, shift administrators(SAs), staff, and charge nurses from inpatient unitsand the ED.

The team identified opportunities for improvementin: (1) “time delays” due to nonstandard communi-cation process, and (2) rework from inaccurate orincomplete information in the original bed requestorder. Inaccuracies generally were related to isolationstatus or patient special needs thatmay not have beenknown or communicated accurately at the time ofbed assignment (eg, continuous albuterol therapy,insulin drips, infectious symptoms or exposures, etc).When these were discovered after the bed assign-ment, significant rework was required that often ledto delays in the admission process.

Admission bed request and assignment includemultiple steps and handoffs, few of which werevisible to the stakeholders once the bed requestwas placed.

Steps in the process include the following:

• ED provider awareness and gathering ofrequired information for accurate initiationof electronic bed request order, which resultsin appropriate assignment of unit, service,team, acuity, isolation, special needs, etc.

dardized electronic tool.

image of Figure 4


• ED order for admission (Figure 4) transmittedto the SA who manually determines bedlocation and team assignment (the ordercreates a visual marker icon on the electronictracking board which also triggers an auto-mated beeper page to the SA).

• Inpatient physician resident or hospitalistteam assignment determined by the SA(visual marker icon generated on the EDtracking board).

• ED provider team gives “early notification”to the assigned team (a verbal “heads up”about the impending admission, with generaldetails of the patient, diagnosis, stage ofcurrent work up and projected ED comple-tion time). This task is documented electron-ically and time stamped.

• Inpatient charge nurse receives notification ofunit assignment from the SA and completedRN/room assignment in the bed requestsystem form (this again generates a visualmarker icon to note this work in process).

• Inpatient RN contacts ED RN to coordinatetiming of transfer.

Figure 5. Example of measured data regarding steps

Outcomes of this project resulted in the following:

• Improvements in the bed request electronicform to make it “easier” to provide and docu-ment the required information in a consistentand standard fashion with better accuracy

• Defining standard work for each “cycle” of theadmission process and the provider groups(eg,. ED physician team, SA, inpatient chargenurse, admitting team)

• Visibility of each cycle in the admit processwith ability to measure/audit (Figure 5)

• Strategic educational roll out to all stake-holders with an implementation date for thenew process.

Creating visibility in the process has allowedbetter real-time management of delays in thesystem and opportunities for immediate feedback,escalation, and identification of barriers. It has alsohelped to provide data and diminish hearsay/opinion in identifying and determining etiologiesof delays. The icons representing the cycles of thebed request process are time stamped and allow for

in the admission process. Times are in minutes.

image of Figure 5


reports of performance by key groups responsiblefor the standard work, by time of day, and byinpatient unit. Tracking these data weekly withleaders from each area helped to guide our work inthe moment as well as enhanced other hospitalinpatient access projects.

Project 4: Ready to AdmitLike the decision to admit metric, this was not

measured consistently before this project. The firststep was defining standard criteria that representedthe point at which the appropriate ED assessment,stabilization, and interventions were complete andthe patient was ready for transfer to the inpatientfloor from the ED perspective. There was a decisionnot to simultaneously increase resource availabilityoutside theED (eg, ward requests for support servicessuch as CT, ultrasound, laboratory technicians todraw samples, etc) or the queuing that enabled theED to be prioritized when acute assessments wererequested from consultants. The following criteriawere used to define ready to admit:

1. All medications that would be needed withinthe next 2 hours have been started.

2. All studies that would change the immediatedisposition (inpatient ward vs ICU vs home)of the patient are available.

3. All ED-specific procedures have beenperformed.

4. Any interventions and/or consultations thatwere more efficiently performed in the EDenvironment have been started or arranged.

An electronic event and visual marker icon werecreated for the computerized ED locator board tomark this time. Emergency department teammembers were encouraged to discuss as a group(medical huddle) as early as possible after thedecision to admit with the goal of reviewing andestablishing the individual patient's criteria forreadiness to admit. The goal was to create a sharedmental model of the plan of care for each patient.Each team member was empowered to fire thisevent when the work was completed as defined.Setting this mark is the first step in achieving thegoal of 80% of patients leaving the ED within 30minutes of readiness to admit.

Project 5: Inpatient PullAt Seattle Children's, it was typical for resident

admitting teams to come to the ED to evaluatealmost every patient and perform a history andphysical examination before the patient coulddepart the ED, regardless of the patient acuity ordiagnosis. This practice was long standing and had

not been significantly impacted in previous EDadmission LOS efforts. This process was partiallycultural and partially due to concerns from theresident-led admitting teams about communica-tion, resource availability, and timely access torequired patient care services on the inpatientward (eg, senior physician, nursing, laboratory,radiology, consultants). The residents also voicedconcerns about the consistency of the initial EDassessment and handoff, potential changes inpatient condition after the patient arrived on theinpatient ward, and the opportunity for teachingfrom the attending PEM physician. Each of the first3 projects were intended to shorten the ED LOSbut were also intended to facilitate communicationwith and involvement of the admitting team asearly as possible in the process, so that if there didneed to be an evaluation by the inpatient team inED, it was incorporated into the patient's requiredED stay, not added sequentially after the EDevaluation was completed.

To address some of the concerns of the admittingteams and to optimize the overall safety of theadmission process, several initiatives were enactedbefore changing our admission process. First, astandard sign-out system and tool were created andprovided to ED staff at their workstations as well asto the inpatient residents in their printed residentmanual. Sign out from the ED to the inpatient wardreceiving team was most often from resident toresident. Receiving physicians were instructed toensure that the report from the ED provider usedthe standard tool and provided the informationrequired in a standard fashion. The handoff toolencouraged the accepting team physicians todiscuss the patient with the ED attending physicianif they had any concerns or questions, or if they feltthat an in-person ED evaluation was warrantedwhen the ED team suggested otherwise. Second, astandardized acuity and assessment tool was imple-mented in the ED for all admitted patients. Amodification of the Pediatric Early Warning Score(MPEWS)34 has been in use on the medical andsurgical floor at Seattle Children's, and change inthis score is used as a indication of potentialdeterioration and the need for a rapid responseteam evaluation (Figure 6). On arrival and at thetime of decision to admit, the patient's ED nurseuses this tool to assign a score to the patient basedon complexity of past medical history as well as vitalsigns and ED interventions. This score is reported tothe admitting team at the time of the ED handoff andhelps guide the expected response time if the patient“needs” to be seen in the ED before transfer todefinitive admission location.

Figure 6. Electronic worksheet for modified pediatric early warning score (MPEWS).


After the implementation of the standard handoff,ED readiness, and assessment tools, 2 different 1- to2-week small tests of change (trials) were performedto make sure that there were no significant, unfore-seen issues with the new process. The new processdefined patients who did not require an evaluationby the admitting team in the ED. These were patientswith low MPEWS scores and made up most ofadmitted medical patients. For patients with higherMPEWS scores, the inpatient teams would perform afocused and efficient evaluation in the ED before thepatient was transferred to the inpatient ward.

Examples of the metrics gathered are notedin Figure 5, and the trend lines are noted inFigure 7. Overage decrease admission in LOS dataand attainment of initial project goal are notedin Figure 1.

SUMMARYThis process describes an intensive and success-

ful effort to use continual process improvementmethodology to decrease ED admission LOS. This

group of projects centered around increasing EDcapacity by decreasing ED LOS of admitted patientand leveraged the hospital and Department ofPediatrics training, experience, and shared visionsregarding the TPS methodology. Thoroughly evalu-ating the system and assessing existing processesenabled understanding of the current state andidentifying opportunities for waste reduction andsystem improvement. Previous ED attempts atdecreasing LOS for patients had been successfulfor the subset of patients who were discharged fromthe ED but had not been successful at the local levelfor patients who required admission. By using theTPS methodology, engaging staff within and outsidethe ED at all levels, identifying appropriate re-sources in time and staff, and tying results tohospital administrative goals resulted in moreawareness of the issues and opportunities/expecta-tions for improvement. Visual markers (Figure 8),standard work, and provider expectations wereimportant components of the successful planningand implementation. Emergency department ca-pacity was created without increasing physical

image of Figure 6

Figure 7. Example of monthly and 12-week trended data for the ED admission process.


space by decreasing the time admitted patients“needed” to be in the ED before admission to aninpatient unit. Because many of these admissionscoincided with the busiest time in the ED (eveninghours), functional capacity was developed to enable

Figure 8. A, Visual icons for admission and discharge processeson ED electronic locator board. B, A star appears after 1 houradjacent to the decision to admit reminder icon to alert team ofneed for admission decision. The icons are color coded to visuallyremind and update all team members of current status. The colorsused are green (ready to discharge or admit), yellow (decisionmade to discharge or admit, and red (reminder to make a decisionregarding potential admission).

more rapid throughput for all ED patients. Data fromthe ED have shown improved performance metricsfor all patients, including a very low rate of patientswho leave without being seen and decreased periodsof severe overcrowding when compared with theprevious year, even in light of steadily increasing EDpatient volumes. Additional successes with thisproject included further standardization of commu-nication and handoff expectations and presumablymore consistent and safer patient handoffs (yet to bestudied). As with any CPI project, planning, design-ing, and implementing are just the beginning of thecontinual process. It is imperative to continuechecking that the interventions and changes arehaving the desired effects and have not resulted inunexpected outcomes, such as decreased quality orsafety, increased cost, patient dissatisfaction, orother confounders. As the systemmatures, checkingthe data and engaging the staff will reveal opportu-nities for improvement, which should then bestudied and acted upon.

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image of Figure 7


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