Using the Six Sigma Approach to Meet Quality Standards for ...

CARDIAC MEDICATIONS

510 JCOM August 2004 Vol. 11, No. 8 www.turner-white.com

Using the Six Sigma Approach to Meet QualityStandards for Cardiac Medication AdministrationAdrienne Elberfeld, Kathleen Goodman, EdD, and Mark Van Kooy, MD

Abstract• Objective: To improve the quality of patient care

through the correct use and appropriate docu-mentation of aspirin, β blockers, and angiotensin-converting enzyme inhibitors in patients with con-gestive heart failure (CHF) and acute myocardialinfarction (AMI).

• Methods: Six Sigma process improvement method-ology.

• Results: The project team identified drivers ofprocess failure and implemented improvementstrategies, including physician and staff education,stocking aspirin on each hospital floor, and shorten-ing the form that paramedics need to complete. Thehealth system exceeded both internal and externalbenchmarks, and improved performance continuesto be sustained 18 months after implementation.

• Conclusion: A sustained clinical and cultural changein the delivery of care for AMI and CHF patients canbe achieved using the Six Sigma process.

Appropriate administration of aspirin, angiotensin-converting enzyme (ACE) inhibitors, and β blockersplays a critical role in the clinical outcomes of con-

gestive heart failure (CHF) and acute myocardial infarction(AMI) patients. In the setting of AMI, aspirin and β-blockeradministration should begin within 24 hours of the eventand should be prescribed at hospital discharge unless other-wise contraindicated. An ACE inhibitor should be pre-scribed at discharge for patients with a cardiac ejection frac-tion of less than 40% unless contraindicated. Patientshospitalized with CHF should also be discharged on an ACEinhibitor if they have an ejection fraction of less than 40%,again, unless contraindicated. Centers for Medicare & Medi-caid Services (CMS) standards require that in cases where amedical contraindication to the use of 1 or more of thesemedications exists, the physician must document in thepatient’s medical record the reason why the medication wasnot administered, no matter how obvious the contraindica-tion is.

Virtua Health is a 4–community hospital health system in

southern New Jersey that was formed as the result of a merg-er of 2 health systems in 2000. Six Sigma has been adopted asan important tool in improving the business and clinicalprocesses of the new organization.

In this paper, we describe the use of the Six Sigma ap-proach to improve system-wide performance in a clinicallyimportant area that is being used as a key measure of hospi-tal quality by CMS and others.

BackgroundIn the fall of 2001, administration, medical staff leadership,and the board of trustees conducted a joint retreat that includ-ed key physicians from throughout the organization. One ofthe principal goals of the retreat was to examine the organi-zation’s current quality measures, align them with CMS stan-dards, and ensure consistency in the quality of patient care.

The reported performance of the system in the area ofadministration of appropriate medication to patients withCHF and AMI was below the level required by CMS. How-ever, it was suspected that there were serious deficiencies inthe accuracy of the data, and the contribution of deficient clin-ical performance was unclear at the time. During subsequentreview, physician directors for cardiac care identified actualdeficiencies in the proper administration of aspirin, ACE in-hibitors and β blockers to CHF and AMI patients. As a result,the medical staff recommended that cardiac medication ad-ministration become a goal for the system.

Senior leadership decided to launch a Cardiac Program ofExcellence (POE), which began in January 2002. The programwas designed to meet the physical, psychosocial, education-al, and spiritual needs of cardiac patients and their familiesacross the care continuum. The goal is a coordinated programthat incorporates state-of-the-art technology, high-qualitycare, best practice standards, and direct linkages betweenproviders, sites, and phases of care. The goals of the POEwere supported by the designation of cardiac medicationadministration as a global organizational goal for the man-agement incentive compensation program for 2002.

From Virtua Health, Marlton, NJ.

POE leadership initially chose to use conventional ap-proaches to address the cardiac medications challenges. Out-come analysts were assigned to review 100% of CHF andAMI discharge charts for adherence to CMS standards.Chart review results for all hospitals were reported quarter-ly using a data scorecard designed by POE leadership fol-lowing the retreat. Medical staff leadership was asked tosupport improved physician performance by interveningwith physicians who had a pattern of noncompliance. Firstquarter 2002 data revealed no significant improvement insystem performance on the cardiac indicators. The lack ofprogress led to a decision by leadership to employ the SixSigma approach, used throughout the organization as part ofa comprehensive process improvement and change man-agement tool kit. In June 2002, a Cardiac Medication SixSigma project was initiated with full senior leadership sup-port and commitment.

The Six Sigma ApproachSix Sigma is a structured, data-driven, problem-solvingapproach first developed by Motorola in the mid-1980s [1].It incorporates and builds on prior problem-solving meth-odologies such as total quality management and continuousquality improvement with several new elements added.These include (1) initiating the improvement effort by solic-iting customer requirements, (2) rigorous confirmation ofmeasurement system and project data accuracy, (3) clear pro-ject deliverables and timelines, and (4) systems and struc-tures to detect and rapidly react to backsliding of project-driven improvements after the project has closed. Six Sigmabegan to be deployed in the health care industry in approxi-mately 1999 after some initial doubt about the viability of theapproach in this sector [2].

The Six Sigma process includes 5 phases: Define, Measure,Analyze, Improve, and Control (DMAIC) [3] (Table). Eachphase has 3 specific deliverables that keep the team focusedon its tasks. There are several key roles in a Six Sigma project.The Sponsor is usually a senior manager who can allocateresources and make decisions to implement team recom-mendations. The Process Owner is typically a manager re-sponsible for the process being targeted for improvement.The Black Belt is a full-time Six Sigma expert drawn frommiddle management ranks. Black Belts are most commonlyhigh-performing individuals who are assigned to the role forup to 3 years, in part as a career development opportunity.They typically return to a leadership role in the organizationupon completion of their time as a Black Belt. Green Beltsreceive the same training as a Black Belt and continue in theirusual positions in the organization, allocating 15% to 30% oftheir time to a project, most often in their department. Teammembers are drawn from the front line individuals doing thework of the process under review. Team member training is

done as the project progresses through the DMAIC phases ina “just in time” fashion.

Cardiac Medication Project Define PhaseThe first step in the project was creating a team. Because theorganization consists of 4 hospitals, the team needed repre-sentatives from key disciplines and all 4 sites. The vice pres-idents of quality and physician services were identified asthe 2 system sponsors for the project. The administrativeleader responsible for the Cardiac POE was the ProcessOwner and Green Belt. A full-time Black Belt led the project.

The cardiac medications team consisted of 2 nurse man-agers, a critical care nurse manager, 2 staff nurses, an emer-gency department nurse, a nurse educator, 2 clinical phar-macists, a paramedic, an outcomes analyst, a case manager,a health information manager, and 3 physician champions.Ad hoc members of the team included an information sys-tems analyst and finance approver. In July 2002, the teambegan meeting on a weekly basis to develop the initial objec-tives of the project and to establish the key project metrics.

Physicians are a unique group regarding process improve-ment activities. They are deeply involved in the clinical pro-cesses yet rarely can attend weekly team meetings. The 3 phy-sician champions for this project were updated weekly by theProcess Owner/Green Belt and involved in discussions asnecessary. Establishing a close working relationship with themedical staff leaders was important to balance the medicalstaff’s support for making process changes while respectingthe time constraints and limited availability of the physicianchampions. Sponsors and senior leadership were providedwith frequent updates during each phase of the project.

Measure PhaseThe team’s first Measure Phase tasks were to establish the qual-ity of the current data and the consistency of chart reviews anddecide on which data should be reported to the organization.The data measurement portion of the project focused on theadherence to CMS standards for CHF/AMI patients, with per-formance assessment based on proper administration of med-ications, proper identification of contraindications, and properdocumentation practices. Quality review analysts, members ofthe quality department with responsibility for chart abstractionand data collection for all quality efforts in the system, collect-ed and analyzed the data for defects. Adefect was identified asfailure to administer a β blocker, ACE inhibitor, or aspirin inpatients with AMI or CHF according to CMS standards. Theteam was responsible for identifying all defects and determin-ing their causes. Analysts reviewed all AMI and CHF charts forthe duration of the project.

Prior to data collection and reporting of initial process per-formance, the Six Sigma approach requires analysis of the

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QUALITY IMPROVEMENTREPORTS FROM THE FIELD

accuracy of the measurement system used to collect the data.The team used a measurement systems accuracy tool (termedGage R&R) to examine the current chart review process forreliability. To complete this step, the Black Belt and the teamidentified a gold standard for the measurement system.Twenty charts were reviewed by expert reviewers for eachCMS standard and were identified as meeting or failing tomeet the standard. Each quality review analyst reviewed eachchart and their performance was compared with peers andwith the gold standard. The team found serious inconsisten-cies in the data collection process. Chart reviewers agreedwith the gold standard and with each other on whether achart met performance criteria as little as 45% of the time.

Faced with this level of inconsistency in the data collec-tion system, a WorkOut involving case management direc-

tors and outcome analysts was held in the early fall to devel-op standard operating procedures based on CMS standards.A WorkOut is a 1- to 2-day session in which people who dothe actual work are empowered to develop improvements inan existing process. Decision makers are present at the con-clusion of the session and there is immediate closure with aspecific action plan to implement the identified improve-ments. The team developed standard operating proceduresand a plan to communicate them to the nursing and medicalstaffs so that ambiguity about performance standards wasreduced. The outcome analysts were trained in the data col-lection procedures and their performance was then re-gauged. They showed substantial improvement in the agree-ment within the group and with the gold standard. Thisstandardization gave the team consistent data to work with


CARDIAC MEDICATIONS

Table. Cardiac Medication Six Sigma Project

Phase Deliverables Virtua Actions in Support of Deliverables

Define

Measure

Analyze

Improve

Control

CMS = Centers for Medicare & Medicaid Services; MI = myocardial infarction; SOPs = standard operating procedures. (Adapted with per-mission from Eckes G. Making Six Sigma last: managing the balance between cultural and technical change. New York: Wiley; 2001.)

• Identify process customers and their require-ments

• Identify the boundaries of the project usinghigh level process map

• Complete an approved project-chartering doc-ument

• Develop accurate system for measuring theprocess result

• Develop a detailed drill down on the processflow

• Report the current process performance forthe targeted customer requirement

• Compare the current process performancewith customer requirements

• Identify key drivers that lead to the currentprocess performance

• Identify target for the improved performance

• Determine the statistical relationship betweenthe key process drivers and the process out-come

• Propose and pilot potential solutions• Determine operating ranges for the proposed

process drivers

• Assure accurate measurement of the improvedkey process drivers

• Confirm that improved drivers are deliveringthe targeted process results in actual practice

• Develop a tracking and rapid reaction plan todetect and correct any process backsliding toassure that gains are sustained

• Virtua senior management, board of trustees, and medical staffwere process customers

• Customer requirements included meeting CMS standards for 4thquarter 2002 for all 6 indicators

• All Virtua facilities were included in the project• Project charter approved by sponsors and stakeholders

• Measurement system accuracy revealed < 50% agreementbetween reviewers of reference charts

• SOPs were developed for chart review leading to 90% agreementbetween chart reviewers

• A detailed process map was completed• Baseline process performance reported• Containment initiated

• Defects due to inconsistent data abstraction reduced• Physician performance and documentation defects characterized• Key defect drivers identified• Improvement target established during Define as CMS-required

level of performance

• Key drivers: (1) lack of data collection SOPs, (2) physician outliers,(3) MI patients presenting with respiratory complaints only

• Solutions: (1) User-friendly discharge form, (2) physician leader-ship intervention with outlier physicians, (3) aspirin administrationto patients presenting with respiratory complaints

• Proposed solutions piloted with excellent results (all 6 requirementsabove CMS specifications)

• Containment removed

• Measurement system accuracy reconfirmed• Targeted results achieved• Control charts and response plan developed and implemented• Project documentation completed, project completion agreement

signed off by sponsor and process owner



during the project. It also had a beneficial effect on physicianacceptance and willingness to approach outlier medical staffmembers since the physician leaders now knew they hadaccurate data, perhaps for the first time.

The next step was to determine a baseline measurement ofthe organization’s actual performance on the CMS cardiacindicators. Any process result that does not meet customerexpectations is a “defect.” Process performance is reported asDPMO (defects per million opportunities), which is the num-ber of defects that would result from 1,000,000 “passes”through the process. This standardized terminology allowswidely different processes to be compared on a similar basis.The DPMO levels were identified for each indicator for AMIand CHF. Baseline data showed that AMI patients had a 4%defect rate (or 40,230 DPMO) and CHF patients were at a10.2% defect rate (102,804 DPMO). With the team’s goal ofachieving zero defects for each patient group, substantialopportunity for improvement was identified. While perfor-mance for all indicators showed opportunities for improve-ment, the greatest opportunities and the initial focus of theteam was around the administration of a β blocker within 24 hours of admission and prescription of an ACE inhibitor atdischarge for AMI patients.

By October 2002, the team was concerned about the orga-nization’s ability to meet the project goals of achieving CMS-required performance for the fourth quarter of the year. Theteam recommended that leadership place the project in con-tainment phase. Containment is the application of explicitlyunsustainable resources to immediately improve a process,protecting the customer from unacceptable defects. Not allSix Sigma projects employ containment. In this case, howev-er, immediate results were desired. Containment steps in thiseffort included the following:

• All critical care managers across the system wereeducated on the CMS cardiac medication stan-dards and recruited to do a daily patient censusreview to identify patients with a potential dis-charge diagnosis of AMI and/or CHF.

• Triage nurses in each emergency departmentwere designated as the point person for all pa-tients with a related AMI diagnosis, and scriptswere developed to provide nurses with the ques-tions needed to obtain required information anddocumentation.

• Case managers, outcome analysts, and clinicalpharmacists completed daily chart reviews basedon daily census reports. When necessary theycontacted physicians for orders or documentationof contraindications.

This interdisciplinary containment effort ensured that theCMS standards for the 6 cardiac medication requirementswere achieved while the DMAIC process continued todevelop sustainable and more fundamental improvements.In instances where these CMS standards were not beingachieved, nursing and case management staff memberswere given the responsibility and means to obtain orders forthe required medications or documentation of contraindica-tions to the otherwise required medications. Examples ofthese tools included reminder stickers on the progress notesand a new cardiac-specific discharge instruction sheets thatmade it easy for physicians to document administration of orcontraindications to the required medications at the time ofpatient discharge.

The team and leadership chartered the specific contain-ment interventions noted above and allocated the necessaryresources. They established time frames and milestones forremoval of the containment interventions. Fourth quarter2002 results met all CMS standards, and the system achievedthe stretch goal of 97% overall adherence to the 6 cardiacmedication standards. The next step was to further analyzethe data and identify changes that could be made to the cur-rent process to sustain improvements without the extensiveresources and efforts employed in containment.

Analyze PhaseAs the project entered the Analyze phase, the team began tomeet on a biweekly basis. Activities included data analysisand confirmation of the improved integrity of the data col-lection process. In addition, the team expanded involvementto other key constituents outside the core team by includingmore of the nursing and medical staff in education and feed-back activities.

Team members brainstormed possible causes of perfor-mance variation, which they linked to a detailed process map.Important process drivers included physician documentationand clinical practice, nursing practice, educational level ofclinicians about core measures, paramedic involvement, doc-umentation of care delivery and contraindications, and emer-gency department operations. The team found that several ofthe drivers were directly linked to process failure. Physicianswere not fully aware of the CMS documentation requirementsfor medication contraindications. They were surprised to findthat even very obvious reasons for withholding medications,such as compromised kidney function (ACE inhibitors) orbleeding disorders (aspirin), required what some of themthought to be repetitive and unnecessary documentation.Paramedics who had provided the correct treatment andmedications in the prehospital phase often documented theiractivities while going to their next call and provided only ver-bal communication to the emergency department staff.

Written documentation was forwarded to the medical recordsdepartment days or even weeks later. This led to inadequatedocumentation on the medical record when their documenta-tion failed to reach the inpatient record. Understanding ofthese process drivers could have been obtained by otherprocesses, but the rigor of the Six Sigma approach helpedteam members to understand the circumstances leading tothese failure modes and to constructively design improvedsystems and educational efforts to successfully address them.

Improve PhasePhysician compliance data obtained from chart reviewshowed that the majority of defects involving physicians weredue to lack of adequate documentation of contraindications tomedication use. In these instances, the physicians had appro-priately withheld medications but did not document whatthey felt were glaringly obvious contraindications. This led toa failure to meet the standard. Educating physicians about therequirements and streamlining documentation of contraindi-cations led to improved performance in this area. Physicianchampions followed up directly with the few physicians whohad quality of care issues such as failure to order an ACEinhibitor or β blocker when indicated. Providing critical feed-back to physician colleagues can be difficult for medical staffleaders. This activity was made easier by the high level of reli-ability of the data and the communication of the data valida-tion methods to the physicians. The team was confident in theoverall level of care being delivered. They identified and actedon the need to put support mechanisms in place to ensure allphysicians remained in compliance both with actual practiceand with documentation.

Data were also analyzed by individual nursing units.Critical care and cardiac step-down units were identified ashaving the greatest opportunities for improvement in ad-ministration of discharge medications. Nursing, workingcollaboratively with the interdisciplinary team, identifiedpatients requiring specific discharge medications and theneed to communicate this information to the primary or con-sulting physicians during the discharge visit.

Staff education was also important. Clinical educatorsdeveloped cardiac competencies and storyboards to reach allnursing shifts. The outcome analysts obtained CMS litera-ture (posters, stickers, and handouts) to further educatenursing and medical staff. The team revised the CHF path-way and patient education booklets in accordance with CMSstandards and distributed the revised booklets throughoutthe organization. AWorkOut was held to develop a standardAMI pathway in delivery of care for the patient as well aspatient education materials.

The team also analyzed patients admitted through theemergency department with a final diagnosis of AMI. Througha chi-square analysis for differences between subgroups, the

project team looked at gender, age, and admission day of theweek to see if these were factors in the delivery of care. Thedata showed that these factors were not statistically significant.Instead, the data indicated that the opportunity to administeraspirin within 24 hours was missed between the care deliveredin the emergency department and admission to the nursingunit. Because aspirin was not stocked on individual hospitalfloors, nurses often did not administer the medication until thesecond hospital day, thus missing the initial 24 -hour window.As a result of this data analysis, aspirin was stocked on eachhospital floor by pharmacy, enabling nurses to administer itwithin 24 hours of admission.

Paramedics were identified as another group of care-givers who could potentially administer aspirin within 24 hours of admission. As noted earlier, the data showed thatthe mobile intensive care unit (MICU) documentation recordoften was not on the inpatient chart. This caused the systemto miss documentation of cases where aspirin had beenadministered appropriately. A root cause of the problem wasthat the paramedics did not have sufficient time to completethe form. A team created a shortened MICU documentationform to give essential information as a reference until the for-mal documentation reached the chart.

Further analysis of AMI patients who did not receiveaspirin within 24 hours when treated by the paramedicsshowed that patients presenting with respiratory distressaccounted for all of the defects for this standard that re-mained after the initial round of improvements. Apolicy wasadopted in which all patients presenting with respiratory dis-tress received aspirin if they had no contraindications. Thisdriver of process failure would have been very difficult to dis-cover by other improvement methodologies and was a keystep in reaching success with the aspirin standard.

The data also showed a strong correlation between usingcardiac-specific discharge instructions and compliance withthe CMS standards. Therefore, the Cardiac POE and physi-cian champions developed a standard discharge instructionform to be used for all AMI and CHF patients. The organi-zation’s Nursing Executive Council and clinical educatorsled the initiative to address the issues of accessibility andavailability of the form on all nursing units so that the rightform was available at the right time for physicians to use.

Control PhaseThe health system used multiple sources to analyze and dis-tribute performance data. To ensure the sustainability of theproject, performance data need to be timely and consistent.The team identified everyone who reported data related tothe CMS standards. A flow chart was developed to ensurethat data were distributed according to standard practice to key stakeholders. This included the monthly statistical re-port based on the outcome analysts chart reviews, quarterly


CARDIAC MEDICATIONS

quality reports for the organization, and reports to the med-ical advisory committee.

A Failure Modes and Effects Analysis was performedprior to project closeout to examine ways in which the newprocesses could fail. The team planned for these failures andcreated systems and structures to reduce the likelihood ofdata collection errors. These interventions included a stan-dardized data collection form with more check boxes andless narrative entry, periodic regauging of staff, and use of astandard, single source of data across the health system witha reduction in the use of ad hoc reports. Control charts wereimplemented to make process performance visible and todistinguish special cause from common cause variation inthe results.

Key Learnings and ResultsThis project focused on evidence-based indicators for thesecond largest population of patients within the system.Based on the data analysis and key learnings through thecontainment process, the team developed many improve-ment initiatives to sustain change. The process was stream-lined, incorporating best practices from the interdisciplinaryteams. Standard operating procedures for the delivery ofcare to cardiac patients were implemented by all disciplinesat all 4 system hospitals.

Pilot data collection revealed inconsistent availability ofpatient census with diagnosis for nursing and case manage-ment. The root cause was identified as an integration prob-lem between the patient care information system and the case



Date

Dear Doctor:

I have reviewed the chart of your patient (INITIALS/MR#). Documentation of the patient’s care did not satisfythe JCAHO/PRO criteria for patients with MI/CHF for the following reasons:

CHF

❏ Ejection fraction not documented

❏ ACE-I not administered or contraindication to ACE-I not documented

❏ Patient not given instructions upon discharge to monitor weights

❏ Patient not given instructions upon discharge for medications or follow-up visits

AMI

❏ Aspirin not administered within 24 hours or contraindication not documented

❏ Beta blocker not administered within 24 hours or contraindication not documented

❏ Aspirin not prescribed at discharge

❏ Beta blocker not prescribed at discharge

❏ ACE-I not administered to patient with LVEF < 40%

❏ Patient not given instructions about smoking cessation

In the future please be sure to pay careful attention to these issues when documenting on your patients withCHF or AMI. The guidelines can be found at the American College of Cardiology Web site at ACC.org. The goalof the Cardiac Program of Excellence is to ensure that outpatients with CHF/AMI are receiving care consistentwith the guidelines.

Please consider using the Cardiac Discharge instruction sheet to help improve documentation and complianceby your patients.

Thank you.

Co-Medical Director Cardiac Program of Excellence

Figure. Letter to outlier physicians.


CARDIAC MEDICATIONS

management information system. The team resolved thisproblem with assistance from the organization’s informationservices department. Another finding was the inconsistencyin physician compliance with completion of discharge in-structions. When the cardiac discharge instructions weremoved to the front of the patient’s chart, there was 100% com-pliance with the use of the form and 100% compliance withCMS standards. Therefore, this became a best practice incor-porated within the nursing departments across the system.

Consistent practice of interdisciplinary patient care was themain reason for the success of the project, but it was clearlyidentified that the nursing departments were the most impor-tant groups in the process. There was a need for a nursingchampion at each campus to lead initiatives of the POE. Thisrealization resulted in the appointment of a nurse leader with-in each hospital to coordinate POE activities at the local level.

Also key to the success of the project was physician in-volvement. Physician leaders were more comfortable ad-dressing outlier physician behavior when they were confi-dent that the data were accurate. Medical staff leadershipapproved the development and implementation of a corre-spondence letter between the physician champion and allphysician outliers (Figure). The correspondence letter servedto facilitate the physician-to-physician communication andcontinued to allow a formal method of tracking physician-generated defects to achieve the CMS standards.

All these improvements have allowed the initiatives ofthe project to successfully continue. The Cardiac POE lead-ers continue to meet monthly with nursing and physician

champions to review trending data. The organization con-tinues to challenge its managers and caregivers by maintain-ing this as the global quality goal.

The improvements made through the project deliveredtargeted results, meeting all CMS indicators in the fourthquarter of 2002. The project closed out in July 2003 andresults have been sustained through the first quarter of 2004.Control charts are reviewed monthly to identify any deteri-oration in the process. Quality initiatives continue with con-current chart reviews and annual reviews of core measuresand the interdisciplinary and continuum of care model byoutcome analysts. MICU staff has modeled their data collec-tion process after the acute care process, measuring theadministration of aspirin within 24 hours on the same AMIpopulation. Future quality initiatives include evaluating out-come indicators based on mortality rates, readmissions, andlength of stay.

Corresponding author: Mark Van Kooy, MD, Ste. 202, 94 Brick Rd.,Marlton, NJ 08053

References1. Harry M, Schroeder R. Six Sigma. New York: Doubleday;

2000.2. Pande PS, Neuman RP, Cavanagh RR. The Six Sigma way:

how GE, Motorola, and other top companies are honingtheir performance. New York: McGraw-Hill; 2000.

3. Chassin MR. Is health care ready for Six Sigma quality?Millbank Q 1998;76:565–91, 510.

Copyright 2004 by Turner White Communications Inc., Wayne, PA. All rights reserved.

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