Original Research—Head and Neck Surgery
Lean Six Sigma Applied to Ultrasound Guided Needle Biopsy in the Head and Neck
Otolaryngology– Head and Neck Surgery 2014, Vol. 151(1) 65–72 Ó American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0194599814528659 http://otojournal.org
Bruce H. Matt, MD, MS1, Heather K. Woodward-Hagg2, Christopher L. Wade, MD3, Penny D. Butler2, and Mimi S. Kokoska, MD1,2
No sponsorships or competing interests have been disclosed for this article.
Abstract Objectives. (1) Confirm the positive value stream of officebased ultrasound using Lean Six Sigma; (2) demonstrate how ultrasound reduces time to diagnosis, costs, patient inconvenience and travel, exposure to ionizing radiation, intravenous contrast, and laboratory tests. Study Design. Case series with historical controls using chart review. Setting. Tertiary Veterans Administration Hospital (universityaffiliated). Subjects and Methods. Patients with a consult request or decision for ultrasound guided fine needle aspiration (USFNA) from 2006 to 2012. Process evaluation using Lean Six Sigma methodologies; years study conducted: 20062012; outcome measurements: type of diagnostic tests and imaging studies including CT scans with associated radiation exposure, time to preliminary and final cytopathologic diagnosis, episodes of patient travel. Results. Value stream mapping prior to and after implementing office-based ultrasound confirmed the time from consult request or decision for USFNA to completion of the USFNA was reduced from a range of 0 to 286 days requiring a maximum 17 steps to a range of 0 to 48 days, necessitating only a maximum of 9 steps. Office-based USFNA for evaluation of head and neck lesions reduced costs, time to diagnosis, risks and inconvenience to patients, radiation exposure, unnecessary laboratory, and patient complaints while increasing staff satisfaction. In addition, office-based ultrasound also changed the clinical management of specific patients. Conclusion. Lean Six Sigma reduces waste and optimizes quality and accuracy in manufacturing. This is the first known application of Lean Six Sigma to office-based USFNA in the evaluation of head and neck lesions. The literature supports the value of office-based ultrasound to patients and health care systems.
Keywords lean management, Six Sigma methodology, head and neck masses, ultrasound, fine needle aspiration, cytologic interpretation Received August 27, 2013; revised February 10, 2014; accepted February 28, 2014.
Introduction The evaluation, diagnosis, and management of suspected neck masses are important services offered by otolaryngologist–head and neck surgeons. Patients with head and neck symptoms or a possible neck mass come to an otolaryngologist for the proper assessment and treatment of what is usually a stressful personal situation. Timely and accurate information for the patient allows for appropriate and timely medical treatment, while reducing anxiety and costs to the patient or payer, and optimizes the use of resources for the patient, physician, and institution. In the case of head and neck cancer, clearly lower stage cancers, which are presumably diagnosed earlier, have a better prognosis and survival than late stage or widely metastatic tumors.1-5 1
Department of Otolaryngology–Head & Neck Surgery, Indiana University School of Medicine, Indianapolis, Indiana, USA 2 Systems Redesign, Richard L. Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA 3 Department of Pathology and Laboratory Medicine, Richard L. Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA This article was presented at the 2013 AAO-HNSF Annual Meeting & OTO EXPO; September 29-October 3, 2013; Vancouver, British Columbia, Canada. Corresponding Author: Bruce H. Matt, MD, MS, Department of Otolaryngology–Head & Neck Surgery, Indiana University School of Medicine, 705 Riley Hospital Drive, Suite 0860, Indianapolis, IN 46202-5230, USA. Email: [email protected]
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Factors that influence productivity and efficiency include ‘‘infrastructure, human resource management, scheduling variation, process flow, technology, and information management limitations.’’6 We had concerns of inefficiencies in the existing process for obtaining guided needle biopsies of head and neck masses. Consequently, we chose to apply widely accepted and powerful methodologies7 to improve our processes for managing patients with a known or suspected but non-palpable or illdefined mass in the head or neck. The approaches we utilized in conjunction with ultrasound guided fine needle aspiration (USFNA) were Lean management and Six Sigma. Lean management principles were initially used in manufacturing, primarily in Japan by Toyota,8 and are largely attributed to Taiichi Ohno.6 The goal of Lean management is to remove waste from a process, so the remaining work is value-added while serving the customer’s needs.8 The journey involves identifying which steps in a process are value-added and non–valueadded. By removing non–value-added steps, waste and inefficiencies are reduced. Six Sigma refers to a quality program to reduce variation, prevent defects, and deliver high value to end users.6,9,10 It was first used by Motorola in the 1980s.11 Taner12 succinctly described Six Sigma: Six Sigma methodology is one of the most powerful performance improvement tools that are changing the face of modern healthcare delivery today. It is embraced by many organisations and industries involved in manufacturing and services as a costeffective way to improve quality and productivity. As a method to eliminate variation and defects, Six Sigma makes use of a structured approach named DMAIC to find the root causes behind problems and to drive processes toward near-perfection.13 The define, measure, analyse, improve and control (DMAIC) is a five-step improvement cycle with the aim to continuously reduce errors: (1) Define the problems, clarify scope and define goals. (2) Measure the current performance, gather and compare data, refine problems/goals. (3) Analyse by identifying sources, gaps and root causes of errors and analyse best practices. (4) Improve by conducting trials to eliminate root causes, testing various solutions, measuring results, standardising solutions and, implementing the improved processes by designing creative solutions to fix and prevent problems. (5) Control the performance of the new process by institutionalizing improvements and putting a mechanism for ongoing monitoring in place.14 We report the use of a combined Lean Six Sigma methodology to improve efficiency and quality of care in the
management of patients with a non-palpable or poorly defined mass in the head or neck in a large and tertiary-level Veterans Administration Hospital–university-affiliated otolaryngologic practice. The senior author (MSK) has previously shown that office-based USFNA of the head and neck is a cost-effective means of evaluating masses of the head and neck.15,16
Methods Both the Human Research Protection Program and the US Department of Veterans Affairs deemed Institutional Review Board (IRB) approval was not required for this study, as this project was a quality improvement project. Since this project was designed to assess internal operations, the project is not considered to be research; United States Title 45 Code of Federal Regulation part 46 does not apply. The Indiana University IRB Office and the Indianapolis VA Research and Development Office both confirmed there was no need for formal IRB review.
Setting The Richard L. Roudebush Veterans Administration Hospital in Indianapolis, Indiana, is a 159-bed tertiary-care medical center17 affiliated with the Indiana University School of Medicine. Approximately 60,000 patients (including 3700 women veterans) treated by the Indianapolis VA Medical Center require over 613,000 outpatient visits and almost 7900 inpatient episodes of care yearly. The Veterans Healthcare System is the largest health care system in the United States.18
Study Design Value stream mapping and process mapping were completed before (current state) and after (future state) implementation of office-based USFNA in an outpatient otolaryngology clinic in a tertiary veterans hospital. The current state map was applied to confirm the waste and non–value-added steps beginning from consultation request to attaining the cytologic diagnosis.
Subject and Methods The process of obtaining an USFNA to further evaluate a neck mass before implementation of Lean Six Sigma (January 2006 to December 2008) were compared to the process after implementation of Lean Six Sigma (January 2009 to December 2012). In general, our approach to treating patients who required an USFNA of the head and neck followed the process that was in place during the time period at consultation. A Sonosite (Sonosite, Bothell, Washington) ultrasound machine was used for all the officebased USFNA in the Otolaryngology clinic. A cytopathologist provided immediate preliminary assessment of adequacy with or without a preliminary diagnosis at the time of USFNA. Surgilube (Savage Laboratories, Melville, New York) was used as the interface medium between the transducer and subject in the office-based USFNA because we have previously shown that there is significantly less background artifact compared to commonly used ultrasound gels.19
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The patient flow from the referral to otolaryngology to final cytopathologic diagnosis was evaluated. Lean Six Sigma methodologies were used to develop a value stream map. Similar to others,6 we focused on location of events, personnel and communications involved, and information technologies required and considered alternate pathways, key features at each step, and areas of bottlenecking. The care staff and providers included surgeons, nurse practitioners, ultrasonographers, radiologists, patient care clerks, blood draw technicians, and cytopathologists. The goals were to improve the value to patients and reduce frustrations for staff and providers. These objectives included: 1. 2. 3. 4. 5. 6. 7. 8. 9.
Reduce time to diagnosis. Reduce cost to arrive at a diagnosis. Reduce time from referral to FNA evaluation. Eliminate unnecessary testing or studies. Reduce trips to our facility and visits for the patient. Streamline medical management. Maintain or improve diagnostic accuracy. Reduce risk to the patient. Changing patient management.
One way to improve timeliness of care for our patients was to use ultrasound for imaging in the clinic. Ultrasound has become more important for the acute management of patients in the clinic. Ultrasound imaging allows for quicker evaluation of masses and improves accuracy and yield of fine needle aspiration.20-23 FNA has been used since the 1930s20 for head and neck masses. Providing clinic-based ultrasound evaluation of head and neck masses has been shown to improve services to patients by speeding arrival to diagnosis and reducing overall costs.20,21,23 Office-based ultrasound was implemented in an effort to improve the service to our patients.
3.
4.
5.
Statistics Confidence intervals and P-values were calculated using Excel (Microsoft, Redmond, Washington). One-tailed t test was used to obtain P-values. 6.
Results Key Findings Our pre- (Figure 1) and post-value (Figure 2) stream maps are listed in the figures.
7. 1. Reduce time to diagnosis. By redesigning a shorter value stream, we were able to reduce the time from decision for FNA to performing USFNA. We reduced the time from a maximum of 286 days to a maximum of 48 days (mean change 32.8 6 7.0 days; P \ .00001; mean 6 95% confidence interval) (Table 1). 2. Reduce cost to arrive at a diagnosis. Our final state reduced costs by reducing patient trips to the facility and eliminating a formerly requisite CT
scan and its attended pre-scan renal function blood tests and coagulation profiles and trimmed the number of phone calls and the employees’ time involved in coordinating all of these studies and communications. The redesigned process also eliminates the cost of intravenous (IV) access and IV hydration for the CT scan. Typically a CT scan of the neck with IV contrast at our universityassociated hospital will cost $1739, which does not include the radiologist’s reading fee. The costs for renal testing are $40 each for creatinine and blood urea nitrogen, while the coagulation profile is expected to be $64 for PT/PTT and $121 for a complete blood count. This does not include any risk and costs of any adverse events from the patient being off anti-coagulants for the CT and FNA. Reduce time from USFNA to final cytopathologic diagnosis. By streamlining our process, we changed this parameter from an average of 6 days down to an average of just 2.3 days (mean 6 95% confidence interval; mean change 3.7 6 3.6 days, P \ .03) (Table 1). Eliminate unnecessary testing. By using ultrasound instead of CT for localization, as mentioned earlier, the need for CT with ionizing radiation and the attendant blood work was eliminated. In addition, patients were not routinely taken off of anticoagulation prior to USFNA in the post-state. Reduced trips to our facility and reduce visits for the patient. In the pre-intervention state, the patient was forced to undertake 0 to 5 additional trips to our facility. In our improved post-state this was reduced to 0 to 2 additional trips. Fewer trips means less monetary cost to the patient and the organization, both in direct transportation costs and in indirect cost such as time away from work and family, loss of income from missing work, and so on. In the VA health system, travel pay to patients adds millions of dollars to the system. Therefore, a reduction in patient travel reduces expenditures to the organization as well as the patient. Streamline medical management. We went from a maximum of 17 steps down to a maximum of 9. We also reduced phone calls from a minimum of 3 phone calls (both intra-institution and to patient) to a maximum of 1 phone call to patient. Maintain or improved diagnostic accuracy. USFNA provides improved diagnostic accuracy over nonguided FNA procedures, especially for non-palpable masses. If the sample was inadequate for cellular material or nondiagnostic, more samples could be obtained immediately with the patient still in the exam room. This approach reduces the number of needle aspirations and return visits for repeat USFNA. Accuracy of office-based USFNA has previously been confirmed.15 However, in the pre-state, an ultrasound
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PRE-
Y
Waste
Non-Value Added but necessary
Value Added
Cancel the consult
NP determines need / me of visit
NP reviews consult
Y
Further management
Manage without UTS
N
ENT MD/NP visit need UTS?
Y
ENT MD/NP orders UTS & CT Scan
Pt. returns for results
Clerk sends request to UTS
Results. ENT look up & schedule appt.
UTS receives request
MD performs UTS FNA
Lab Draw: Cr & eGFR (btw UTS & CT)
Need FNA?
CT performed & confirmed
Approx. 17 steps minimum
UTS Tech examines Pt.
Lab Draws: (CBC, INR, & PT/PTT) "stop blood thinners 7 days prior & fasng aer midnight"
ENT calls Pt. to inform them of appt
UTS calls ENT clinic to set me & date
Figure 1. Current state value map. Abbreviations: MD, medical doctor; ENT, ear, nose, and throat; UTS, ultrasound; NP, nurse practitioner; CT, computerized tomography; Cr, creatinine; eGFR, estimated glomerular filtration rate; Pt, patient; CBC, complete blood count; INR, international normalized ratio; PT/PTT, prothrombin time/partial thromboplastin time; FNA, fine needle aspiration; PCP, primary care provider.
MD orders ENT consult
Ultrasound Process Map
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POST-
Waste
Non-Value Added but necessary
Value Added
Cancel consult
NP determines need / time of visit
NP reviews consult
Y
Manage without Ultrasound
Need Ultrasound Assessment?
N
Seen in office
Schedule with other provider (NP)
N
Need Ultrasound Assessment?
Y
Y
Schedule Ultrasound with MD
Follow-up as needed
N
Ultrasound FNA complete?
Y
Card given with phone connection
Y
Discharge to PCP
N
Need Further Evaluation?
Y
Further management
Figure 2. Final state value map. Abbreviations: MD, medical doctor; ENT, ear, nose, and throat; UTS, ultrasound; NP, nurse practitioner; CT, computerized tomography; Cr, creatinine; eGFR, estimated glomerular filtration rate; Pt, patient; CBC, complete blood count; INR, international normalized ratio; PT/PTT, prothrombin time/partial thromboplastin time; FNA, fine needle aspiration; PCP, primary care provider.
MD orders ENT consult
Ultrasound Process Map
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Table 1. Outcomes. Pre-intervention Range
Post-intervention Range
Mean 6 95% Confidence Interval Mean 6 95% Confidence Interval N = 104
Mean 6 95% Confidence Interval
N = 185
Maximum number of steps 17 Time from decision for USFNA Range, 0-286 to USFNA (days) 37.6 6 9.1
9 Range, 0-48 4.8 6 1.1
Time from USFNA to preliminary diagnosis (days) Time from USFNA to final diagnosis (days) Cost of waste tests (CT, blood work) ($)
Range, 0-0 0.10. Range, 0-19 2.3 6 0.67 $0
Range, 0-0 0.10. Range, 0-251 6.0 6 4.7 .$2004/patient
Change
8 fewer steps Reduction of 238 days on high end 32.8 6 7.0 mean fewer days (P \.00001) No change (immediate preliminary cytopathologic assessment) Reduction of 232 days on high end 3.7 6 3.6 mean fewer days (P \.03) .$2004 saved/patient
Abbreviations: USFNA, ultrasound guided fine needle aspiration; CT, computerized tomography.
technician examined the patient prior to a MD radiologist performing the USFNA procedure. In the post-state, the otolaryngologist performed the USFNA evaluation directly. This eliminates the cost of an ultrasound technician without sacrificing accuracy. 8. Reduce risk to the patient. We were able to achieve reduced risk in a number of ways. The post-state eliminated the requisite CT imaging in the prestate and avoided the need for a CT guided needle biopsies if USFNA was not available. None of the patients in the post-state experienced any complications such as hematomas or infections. 9. Changing patient management. We had several cases where as a result of immediate cytologic FNA results, the otolaryngologist’s decision making with regard to USFNA of another site or lesion was altered. In some of these cases, the surgical plan was changed due to the new cytopathologic information, observation was recommended with patient reassurance, or medical treatment was instituted for a mass where non-surgical treatment was indicated. As an example, we found squamous cell carcinoma on USFNA of the primary lesion but saw a thyroid nodule on that ultrasound. At the same visit, we performed USFNA on the thyroid lesion and discovered papillary thyroid carcinoma. This led us to perform a total thyroidectomy instead of a hemithyroidectomy at the time of the extirpative operation. Of note, there was no gain or loss in the number of support staff from the pre-state and post-state time periods.
Discussion Many papers have discussed the challenges and issues in the delivery of health care. Cima6 evaluated overall operating room efficiency using Lean and Six Sigma approach, while
Adams24 used Six Sigma strategies to decrease turnover time for general surgery. At least 177 articles on Lean Six Sigma in health care were published in the past 10 years.25 Of those, only 34 reported process outcomes. Our study shows the application of Lean Six Sigma methodologies to the management of head and neck masses. Previously the senior author (MSK) had reported on process improvements in reducing operating room cancellations.26 Focusing only on orthopedic surgery, a 43% reduction in cancellations was achieved. This provided an estimated savings of $400,000 over 6 months by this one service alone in a system with 13 surgical services. Using a similar approach, we focused on improving the process of obtaining cytologic diagnosis of head and neck masses via USFNA. Our endpoint was tissue diagnosis obtained by USFNA, so this study did not evaluate downstream costs of management such as further imaging and procedures. By applying Lean Six Sigma to a clinical problem (obtaining cytologic diagnosis), we eliminated non–value-added steps, inconvenience and costs to the patient and organization, frustrations in handoffs and communications, risks to patients, and reduced the time to diagnosis. The reduced time to diagnosis from a maximum of 286 days to a maximum of 48 days with a mean reduction 32.8 6 7.0 days (P \ .00001) shows an improvement in outcomes and it also confirms the significant reduction in process variability. In addition, the clinical management of some patients was changed during the USFNA process as immediate cytologic feedback was provided to the otolaryngologist, who could make immediate changes in clinical decision making, such as the need for USFNA of another nodule, lymph node, or abnormal site. Improvements in the efficiency and costs of delivering medical care while maintaining or raising the quality of care does not necessarily require an increase in staffing or personnel (as we have shown in this case). Lean Six Sigma provides the tools for analyzing the process in a step-wise manner to determine what actions are needed to optimize delivery of a service. It can clearly be
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applied with success to a clinical diagnostic process with tangible and intangible benefits to patients and organizations. Health care innovations, process improvements, as well as untoward events in VA have frequently been the bell weather for similar implementations, findings, and improvements in the community and academic health care systems, sometimes decades later. For example, the VA was the first national health care system in the world to develop and utilize a comprehensive electronic medical record system. Its internally developed electronic medical record won the Harvard Innovation Award in 2001. The National Surgical Quality Improvement Program (NSQIP) was developed in VA several decades ago, and the American College of Surgeons has taken the model to offer a surgical quality assessment program to the community and academic health care systems. The first liver transplant surgery in the US was performed in VA.27 Therefore, health care in the VA system is not only applicable to the rest of health care in the US and world; it also frequently leads innovations in health care.
Conclusions We report the use of Lean Six Sigma approach in the diagnostic management of head and neck masses. By applying Lean Six Sigma to USFNA, we identified multiple improvements in the ‘‘current state’’ and reduced time to diagnosis, risks, and costs from referral to final cytopathologic diagnosis of head and neck masses. Timeliness of diagnosis allows for earlier initiation of patient management and treatment. Early diagnosis and treatment are especially critical to survival in patients with head and neck malignancies.1-5 Author Contributions Bruce H. Matt, analyzed data, collected data, wrote article, final approval; Heather K. Woodward-Hagg, designed study, collected data, analyzed data, revised article, final approval; Christopher L. Wade, collected data, revised article, final approval; Penny D. Butler, designed study, collected data, analyzed data, revised article, final approval; Mimi S. Kokoska, designed study, collected data, analyzed data, revised article, final approval.
Disclosures Competing interests: None. Sponsorships: None. Funding source: None.
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4. Teppo H, Alho O-P. Comorbidity and diagnostic delay in cancer of the larynx, tongue and pharynx. Oral Oncol. 2009;45:692-695. 5. Teppo H, Alho OP. Relative importance of diagnostic delays in different head and neck cancers. Clin Otolaryngol. 2008;33: 325-330. 6. Cima RR, Brown MJ, Hebl JR, et al. Use of lean and six sigma methodology to improve operating room efficiency in a high-volume tertiary-care academic medical center. J Am Coll Surg. 2011;213:83-92. 7. Niemeijer GC, Trip A, Ahaus KTB, Does RJMM, Wendt KW. Quality in trauma care: improving the discharge procedure of patients by means of Lean Six Sigma. J Trauma. 2010;69:614618. 8. Womack JP, Byrne AP, Fiume OJ, Kaplan GS, Toussaint J, Miller D. Going lean in health care. In: Institute for Healthcare Improvement. Cambridge, MA: Institute for Healthcare Improvement; 2005. 9. American Society for Quality. Six Sigma overview. http://asq. org/learn-about-quality/six-sigma/overview/overview.html. Published 2013. Accessed July 15, 2013. 10. Aveta Limited. Six Sigma defined—the history of Six Sigma. http://www.sixsigmaonline.org/six-sigma-training-certificationinformation/articles/six-sigma-defined—the-history-of-six-sigma .html. Published 2013. Accessed July 14, 2013. 11. Celano G, Costa A, Fichera S, Tringali G. Linking Six Sigma to simulation: a new roadmap to improve the quality of patient care. Int J Health Care Qual Assur. 2012;25:254-273. 12. Taner MT, Sezen B, Atwat KM. Application of Six Sigma methodology to a diagnostic imaging process. Int J Health Care Qual Assur. 2012;25:274-290. 13. Cherry J, Seshadri S. Six Sigma: using statistics to reduce process variability and costs in radiology. Radiology Management. 2000;42-45. 14. Park SH, Antony J. Robust Design for Quality Engineering and Six Sigma. Hackensack, NJ: World Scientific; 2008. 15. Moberly AC, Vural E, Nahas B, Bergeson TR, Kokoska MS. Ultrasound-guided needle aspiration: impact of immediate cytologic review. Laryngoscope. 2010;120:1979-1984. 16. Akbar NA, Bodenner DL, Kim LT, Suen JY, Kokoska MS. Considerations in incorporating office-based ultrasound of the head and neck. Otolaryngol Head Neck Surg. 2006;135:884-888. 17. Veterans Administration. Pharmacy residency programs. http:// www.indianapolis.va.gov/services/pharmacy/Pharmacy_Residency_ Programs.asp. Published 2013. Accessed August 18, 2013. 18. Veterans Administration. About the Richard L. Roudebush VAMC, Indianapolis, Indiana. http://www.indianapolis.va.gov/ about/index.asp. Published 2013. Accessed August 18, 2013. 19. Royer MC, Davidson DD, Dimitrov RK, Kuo CY, Kokoska MS. Ultrasound gel causes fine needle aspiration artifact? A clear choice. Acta Cytologica. 2012;56:146-154. 20. Ganguly A, Giles TE, Smith PA, White FE, Nixon PP. The benefits of on-site cytology with ultrasound-guided fine needle aspiration in a one-stop neck lump clinic. Ann R Coll Surg Engl. 2010;92:660-664. 21. Robinson IA, Cozens NJ. Does a joint ultrasound guided cytology clinic optimize the cytological evaluation of head and neck masses? Clin Radiol. 1999;54:312-316.
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22. Vowles RH, Ghiacy S, Jefferis AF. A clinic for the rapid processing of patients with neck masses. J Laryngol Otol. 1998; 112:1061-1064. 23. Murray A, Stewart CJR, McGarry GW, MacKenzie K. Patients with neck lumps: can they be managed in a "onestop" clinic setting? Clin Otolaryngol Allied Sci. 2000;25:471475. 24. Adams R, Warner P, Hubbard B, Goulding T. Decreasing turnaround time between general surgery cases: a Six Sigma initiative. J Nurs Adm. 2004;34:140-148.
25. DelliFraine JL, Langabeer JR, Nembhard IM. Assessing the evidence of Six Sigma and Lean in the health care industry. Qual Manag Health Care. 2010;19:211-225. 26. Kokoska M, Welch SB, Stevens T. Process improvements to reduce operating room cancellations. In Applying Lean in Healthcare : A Collection of International Case Studies. Boca Raton, FL: Productivity Press; 2010:179-196. 27. Starzl T, Marchioro T, Vonkaulla K, Hermann G, Brittain R, Waddell W. Homotransplantation of the liver in humans. Surg Gynecol Obstet. 1963;117:659-676.
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Lean Six Sigma Applied to Ultrasound Guided Needle Biopsy in the Head and Neck
Otolaryngology– Head and Neck Surgery 2014, Vol. 151(1) 65–72 Ó American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0194599814528659 http://otojournal.org
Bruce H. Matt, MD, MS1, Heather K. Woodward-Hagg2, Christopher L. Wade, MD3, Penny D. Butler2, and Mimi S. Kokoska, MD1,2
No sponsorships or competing interests have been disclosed for this article.
Abstract Objectives. (1) Confirm the positive value stream of officebased ultrasound using Lean Six Sigma; (2) demonstrate how ultrasound reduces time to diagnosis, costs, patient inconvenience and travel, exposure to ionizing radiation, intravenous contrast, and laboratory tests. Study Design. Case series with historical controls using chart review. Setting. Tertiary Veterans Administration Hospital (universityaffiliated). Subjects and Methods. Patients with a consult request or decision for ultrasound guided fine needle aspiration (USFNA) from 2006 to 2012. Process evaluation using Lean Six Sigma methodologies; years study conducted: 20062012; outcome measurements: type of diagnostic tests and imaging studies including CT scans with associated radiation exposure, time to preliminary and final cytopathologic diagnosis, episodes of patient travel. Results. Value stream mapping prior to and after implementing office-based ultrasound confirmed the time from consult request or decision for USFNA to completion of the USFNA was reduced from a range of 0 to 286 days requiring a maximum 17 steps to a range of 0 to 48 days, necessitating only a maximum of 9 steps. Office-based USFNA for evaluation of head and neck lesions reduced costs, time to diagnosis, risks and inconvenience to patients, radiation exposure, unnecessary laboratory, and patient complaints while increasing staff satisfaction. In addition, office-based ultrasound also changed the clinical management of specific patients. Conclusion. Lean Six Sigma reduces waste and optimizes quality and accuracy in manufacturing. This is the first known application of Lean Six Sigma to office-based USFNA in the evaluation of head and neck lesions. The literature supports the value of office-based ultrasound to patients and health care systems.
Keywords lean management, Six Sigma methodology, head and neck masses, ultrasound, fine needle aspiration, cytologic interpretation Received August 27, 2013; revised February 10, 2014; accepted February 28, 2014.
Introduction The evaluation, diagnosis, and management of suspected neck masses are important services offered by otolaryngologist–head and neck surgeons. Patients with head and neck symptoms or a possible neck mass come to an otolaryngologist for the proper assessment and treatment of what is usually a stressful personal situation. Timely and accurate information for the patient allows for appropriate and timely medical treatment, while reducing anxiety and costs to the patient or payer, and optimizes the use of resources for the patient, physician, and institution. In the case of head and neck cancer, clearly lower stage cancers, which are presumably diagnosed earlier, have a better prognosis and survival than late stage or widely metastatic tumors.1-5 1
Department of Otolaryngology–Head & Neck Surgery, Indiana University School of Medicine, Indianapolis, Indiana, USA 2 Systems Redesign, Richard L. Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA 3 Department of Pathology and Laboratory Medicine, Richard L. Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA This article was presented at the 2013 AAO-HNSF Annual Meeting & OTO EXPO; September 29-October 3, 2013; Vancouver, British Columbia, Canada. Corresponding Author: Bruce H. Matt, MD, MS, Department of Otolaryngology–Head & Neck Surgery, Indiana University School of Medicine, 705 Riley Hospital Drive, Suite 0860, Indianapolis, IN 46202-5230, USA. Email: [email protected]
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Factors that influence productivity and efficiency include ‘‘infrastructure, human resource management, scheduling variation, process flow, technology, and information management limitations.’’6 We had concerns of inefficiencies in the existing process for obtaining guided needle biopsies of head and neck masses. Consequently, we chose to apply widely accepted and powerful methodologies7 to improve our processes for managing patients with a known or suspected but non-palpable or illdefined mass in the head or neck. The approaches we utilized in conjunction with ultrasound guided fine needle aspiration (USFNA) were Lean management and Six Sigma. Lean management principles were initially used in manufacturing, primarily in Japan by Toyota,8 and are largely attributed to Taiichi Ohno.6 The goal of Lean management is to remove waste from a process, so the remaining work is value-added while serving the customer’s needs.8 The journey involves identifying which steps in a process are value-added and non–valueadded. By removing non–value-added steps, waste and inefficiencies are reduced. Six Sigma refers to a quality program to reduce variation, prevent defects, and deliver high value to end users.6,9,10 It was first used by Motorola in the 1980s.11 Taner12 succinctly described Six Sigma: Six Sigma methodology is one of the most powerful performance improvement tools that are changing the face of modern healthcare delivery today. It is embraced by many organisations and industries involved in manufacturing and services as a costeffective way to improve quality and productivity. As a method to eliminate variation and defects, Six Sigma makes use of a structured approach named DMAIC to find the root causes behind problems and to drive processes toward near-perfection.13 The define, measure, analyse, improve and control (DMAIC) is a five-step improvement cycle with the aim to continuously reduce errors: (1) Define the problems, clarify scope and define goals. (2) Measure the current performance, gather and compare data, refine problems/goals. (3) Analyse by identifying sources, gaps and root causes of errors and analyse best practices. (4) Improve by conducting trials to eliminate root causes, testing various solutions, measuring results, standardising solutions and, implementing the improved processes by designing creative solutions to fix and prevent problems. (5) Control the performance of the new process by institutionalizing improvements and putting a mechanism for ongoing monitoring in place.14 We report the use of a combined Lean Six Sigma methodology to improve efficiency and quality of care in the
management of patients with a non-palpable or poorly defined mass in the head or neck in a large and tertiary-level Veterans Administration Hospital–university-affiliated otolaryngologic practice. The senior author (MSK) has previously shown that office-based USFNA of the head and neck is a cost-effective means of evaluating masses of the head and neck.15,16
Methods Both the Human Research Protection Program and the US Department of Veterans Affairs deemed Institutional Review Board (IRB) approval was not required for this study, as this project was a quality improvement project. Since this project was designed to assess internal operations, the project is not considered to be research; United States Title 45 Code of Federal Regulation part 46 does not apply. The Indiana University IRB Office and the Indianapolis VA Research and Development Office both confirmed there was no need for formal IRB review.
Setting The Richard L. Roudebush Veterans Administration Hospital in Indianapolis, Indiana, is a 159-bed tertiary-care medical center17 affiliated with the Indiana University School of Medicine. Approximately 60,000 patients (including 3700 women veterans) treated by the Indianapolis VA Medical Center require over 613,000 outpatient visits and almost 7900 inpatient episodes of care yearly. The Veterans Healthcare System is the largest health care system in the United States.18
Study Design Value stream mapping and process mapping were completed before (current state) and after (future state) implementation of office-based USFNA in an outpatient otolaryngology clinic in a tertiary veterans hospital. The current state map was applied to confirm the waste and non–value-added steps beginning from consultation request to attaining the cytologic diagnosis.
Subject and Methods The process of obtaining an USFNA to further evaluate a neck mass before implementation of Lean Six Sigma (January 2006 to December 2008) were compared to the process after implementation of Lean Six Sigma (January 2009 to December 2012). In general, our approach to treating patients who required an USFNA of the head and neck followed the process that was in place during the time period at consultation. A Sonosite (Sonosite, Bothell, Washington) ultrasound machine was used for all the officebased USFNA in the Otolaryngology clinic. A cytopathologist provided immediate preliminary assessment of adequacy with or without a preliminary diagnosis at the time of USFNA. Surgilube (Savage Laboratories, Melville, New York) was used as the interface medium between the transducer and subject in the office-based USFNA because we have previously shown that there is significantly less background artifact compared to commonly used ultrasound gels.19
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The patient flow from the referral to otolaryngology to final cytopathologic diagnosis was evaluated. Lean Six Sigma methodologies were used to develop a value stream map. Similar to others,6 we focused on location of events, personnel and communications involved, and information technologies required and considered alternate pathways, key features at each step, and areas of bottlenecking. The care staff and providers included surgeons, nurse practitioners, ultrasonographers, radiologists, patient care clerks, blood draw technicians, and cytopathologists. The goals were to improve the value to patients and reduce frustrations for staff and providers. These objectives included: 1. 2. 3. 4. 5. 6. 7. 8. 9.
Reduce time to diagnosis. Reduce cost to arrive at a diagnosis. Reduce time from referral to FNA evaluation. Eliminate unnecessary testing or studies. Reduce trips to our facility and visits for the patient. Streamline medical management. Maintain or improve diagnostic accuracy. Reduce risk to the patient. Changing patient management.
One way to improve timeliness of care for our patients was to use ultrasound for imaging in the clinic. Ultrasound has become more important for the acute management of patients in the clinic. Ultrasound imaging allows for quicker evaluation of masses and improves accuracy and yield of fine needle aspiration.20-23 FNA has been used since the 1930s20 for head and neck masses. Providing clinic-based ultrasound evaluation of head and neck masses has been shown to improve services to patients by speeding arrival to diagnosis and reducing overall costs.20,21,23 Office-based ultrasound was implemented in an effort to improve the service to our patients.
3.
4.
5.
Statistics Confidence intervals and P-values were calculated using Excel (Microsoft, Redmond, Washington). One-tailed t test was used to obtain P-values. 6.
Results Key Findings Our pre- (Figure 1) and post-value (Figure 2) stream maps are listed in the figures.
7. 1. Reduce time to diagnosis. By redesigning a shorter value stream, we were able to reduce the time from decision for FNA to performing USFNA. We reduced the time from a maximum of 286 days to a maximum of 48 days (mean change 32.8 6 7.0 days; P \ .00001; mean 6 95% confidence interval) (Table 1). 2. Reduce cost to arrive at a diagnosis. Our final state reduced costs by reducing patient trips to the facility and eliminating a formerly requisite CT
scan and its attended pre-scan renal function blood tests and coagulation profiles and trimmed the number of phone calls and the employees’ time involved in coordinating all of these studies and communications. The redesigned process also eliminates the cost of intravenous (IV) access and IV hydration for the CT scan. Typically a CT scan of the neck with IV contrast at our universityassociated hospital will cost $1739, which does not include the radiologist’s reading fee. The costs for renal testing are $40 each for creatinine and blood urea nitrogen, while the coagulation profile is expected to be $64 for PT/PTT and $121 for a complete blood count. This does not include any risk and costs of any adverse events from the patient being off anti-coagulants for the CT and FNA. Reduce time from USFNA to final cytopathologic diagnosis. By streamlining our process, we changed this parameter from an average of 6 days down to an average of just 2.3 days (mean 6 95% confidence interval; mean change 3.7 6 3.6 days, P \ .03) (Table 1). Eliminate unnecessary testing. By using ultrasound instead of CT for localization, as mentioned earlier, the need for CT with ionizing radiation and the attendant blood work was eliminated. In addition, patients were not routinely taken off of anticoagulation prior to USFNA in the post-state. Reduced trips to our facility and reduce visits for the patient. In the pre-intervention state, the patient was forced to undertake 0 to 5 additional trips to our facility. In our improved post-state this was reduced to 0 to 2 additional trips. Fewer trips means less monetary cost to the patient and the organization, both in direct transportation costs and in indirect cost such as time away from work and family, loss of income from missing work, and so on. In the VA health system, travel pay to patients adds millions of dollars to the system. Therefore, a reduction in patient travel reduces expenditures to the organization as well as the patient. Streamline medical management. We went from a maximum of 17 steps down to a maximum of 9. We also reduced phone calls from a minimum of 3 phone calls (both intra-institution and to patient) to a maximum of 1 phone call to patient. Maintain or improved diagnostic accuracy. USFNA provides improved diagnostic accuracy over nonguided FNA procedures, especially for non-palpable masses. If the sample was inadequate for cellular material or nondiagnostic, more samples could be obtained immediately with the patient still in the exam room. This approach reduces the number of needle aspirations and return visits for repeat USFNA. Accuracy of office-based USFNA has previously been confirmed.15 However, in the pre-state, an ultrasound
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PRE-
Y
Waste
Non-Value Added but necessary
Value Added
Cancel the consult
NP determines need / me of visit
NP reviews consult
Y
Further management
Manage without UTS
N
ENT MD/NP visit need UTS?
Y
ENT MD/NP orders UTS & CT Scan
Pt. returns for results
Clerk sends request to UTS
Results. ENT look up & schedule appt.
UTS receives request
MD performs UTS FNA
Lab Draw: Cr & eGFR (btw UTS & CT)
Need FNA?
CT performed & confirmed
Approx. 17 steps minimum
UTS Tech examines Pt.
Lab Draws: (CBC, INR, & PT/PTT) "stop blood thinners 7 days prior & fasng aer midnight"
ENT calls Pt. to inform them of appt
UTS calls ENT clinic to set me & date
Figure 1. Current state value map. Abbreviations: MD, medical doctor; ENT, ear, nose, and throat; UTS, ultrasound; NP, nurse practitioner; CT, computerized tomography; Cr, creatinine; eGFR, estimated glomerular filtration rate; Pt, patient; CBC, complete blood count; INR, international normalized ratio; PT/PTT, prothrombin time/partial thromboplastin time; FNA, fine needle aspiration; PCP, primary care provider.
MD orders ENT consult
Ultrasound Process Map
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POST-
Waste
Non-Value Added but necessary
Value Added
Cancel consult
NP determines need / time of visit
NP reviews consult
Y
Manage without Ultrasound
Need Ultrasound Assessment?
N
Seen in office
Schedule with other provider (NP)
N
Need Ultrasound Assessment?
Y
Y
Schedule Ultrasound with MD
Follow-up as needed
N
Ultrasound FNA complete?
Y
Card given with phone connection
Y
Discharge to PCP
N
Need Further Evaluation?
Y
Further management
Figure 2. Final state value map. Abbreviations: MD, medical doctor; ENT, ear, nose, and throat; UTS, ultrasound; NP, nurse practitioner; CT, computerized tomography; Cr, creatinine; eGFR, estimated glomerular filtration rate; Pt, patient; CBC, complete blood count; INR, international normalized ratio; PT/PTT, prothrombin time/partial thromboplastin time; FNA, fine needle aspiration; PCP, primary care provider.
MD orders ENT consult
Ultrasound Process Map
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Table 1. Outcomes. Pre-intervention Range
Post-intervention Range
Mean 6 95% Confidence Interval Mean 6 95% Confidence Interval N = 104
Mean 6 95% Confidence Interval
N = 185
Maximum number of steps 17 Time from decision for USFNA Range, 0-286 to USFNA (days) 37.6 6 9.1
9 Range, 0-48 4.8 6 1.1
Time from USFNA to preliminary diagnosis (days) Time from USFNA to final diagnosis (days) Cost of waste tests (CT, blood work) ($)
Range, 0-0 0.10. Range, 0-19 2.3 6 0.67 $0
Range, 0-0 0.10. Range, 0-251 6.0 6 4.7 .$2004/patient
Change
8 fewer steps Reduction of 238 days on high end 32.8 6 7.0 mean fewer days (P \.00001) No change (immediate preliminary cytopathologic assessment) Reduction of 232 days on high end 3.7 6 3.6 mean fewer days (P \.03) .$2004 saved/patient
Abbreviations: USFNA, ultrasound guided fine needle aspiration; CT, computerized tomography.
technician examined the patient prior to a MD radiologist performing the USFNA procedure. In the post-state, the otolaryngologist performed the USFNA evaluation directly. This eliminates the cost of an ultrasound technician without sacrificing accuracy. 8. Reduce risk to the patient. We were able to achieve reduced risk in a number of ways. The post-state eliminated the requisite CT imaging in the prestate and avoided the need for a CT guided needle biopsies if USFNA was not available. None of the patients in the post-state experienced any complications such as hematomas or infections. 9. Changing patient management. We had several cases where as a result of immediate cytologic FNA results, the otolaryngologist’s decision making with regard to USFNA of another site or lesion was altered. In some of these cases, the surgical plan was changed due to the new cytopathologic information, observation was recommended with patient reassurance, or medical treatment was instituted for a mass where non-surgical treatment was indicated. As an example, we found squamous cell carcinoma on USFNA of the primary lesion but saw a thyroid nodule on that ultrasound. At the same visit, we performed USFNA on the thyroid lesion and discovered papillary thyroid carcinoma. This led us to perform a total thyroidectomy instead of a hemithyroidectomy at the time of the extirpative operation. Of note, there was no gain or loss in the number of support staff from the pre-state and post-state time periods.
Discussion Many papers have discussed the challenges and issues in the delivery of health care. Cima6 evaluated overall operating room efficiency using Lean and Six Sigma approach, while
Adams24 used Six Sigma strategies to decrease turnover time for general surgery. At least 177 articles on Lean Six Sigma in health care were published in the past 10 years.25 Of those, only 34 reported process outcomes. Our study shows the application of Lean Six Sigma methodologies to the management of head and neck masses. Previously the senior author (MSK) had reported on process improvements in reducing operating room cancellations.26 Focusing only on orthopedic surgery, a 43% reduction in cancellations was achieved. This provided an estimated savings of $400,000 over 6 months by this one service alone in a system with 13 surgical services. Using a similar approach, we focused on improving the process of obtaining cytologic diagnosis of head and neck masses via USFNA. Our endpoint was tissue diagnosis obtained by USFNA, so this study did not evaluate downstream costs of management such as further imaging and procedures. By applying Lean Six Sigma to a clinical problem (obtaining cytologic diagnosis), we eliminated non–value-added steps, inconvenience and costs to the patient and organization, frustrations in handoffs and communications, risks to patients, and reduced the time to diagnosis. The reduced time to diagnosis from a maximum of 286 days to a maximum of 48 days with a mean reduction 32.8 6 7.0 days (P \ .00001) shows an improvement in outcomes and it also confirms the significant reduction in process variability. In addition, the clinical management of some patients was changed during the USFNA process as immediate cytologic feedback was provided to the otolaryngologist, who could make immediate changes in clinical decision making, such as the need for USFNA of another nodule, lymph node, or abnormal site. Improvements in the efficiency and costs of delivering medical care while maintaining or raising the quality of care does not necessarily require an increase in staffing or personnel (as we have shown in this case). Lean Six Sigma provides the tools for analyzing the process in a step-wise manner to determine what actions are needed to optimize delivery of a service. It can clearly be
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applied with success to a clinical diagnostic process with tangible and intangible benefits to patients and organizations. Health care innovations, process improvements, as well as untoward events in VA have frequently been the bell weather for similar implementations, findings, and improvements in the community and academic health care systems, sometimes decades later. For example, the VA was the first national health care system in the world to develop and utilize a comprehensive electronic medical record system. Its internally developed electronic medical record won the Harvard Innovation Award in 2001. The National Surgical Quality Improvement Program (NSQIP) was developed in VA several decades ago, and the American College of Surgeons has taken the model to offer a surgical quality assessment program to the community and academic health care systems. The first liver transplant surgery in the US was performed in VA.27 Therefore, health care in the VA system is not only applicable to the rest of health care in the US and world; it also frequently leads innovations in health care.
Conclusions We report the use of Lean Six Sigma approach in the diagnostic management of head and neck masses. By applying Lean Six Sigma to USFNA, we identified multiple improvements in the ‘‘current state’’ and reduced time to diagnosis, risks, and costs from referral to final cytopathologic diagnosis of head and neck masses. Timeliness of diagnosis allows for earlier initiation of patient management and treatment. Early diagnosis and treatment are especially critical to survival in patients with head and neck malignancies.1-5 Author Contributions Bruce H. Matt, analyzed data, collected data, wrote article, final approval; Heather K. Woodward-Hagg, designed study, collected data, analyzed data, revised article, final approval; Christopher L. Wade, collected data, revised article, final approval; Penny D. Butler, designed study, collected data, analyzed data, revised article, final approval; Mimi S. Kokoska, designed study, collected data, analyzed data, revised article, final approval.
Disclosures Competing interests: None. Sponsorships: None. Funding source: None.
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