Thesis MBA Special Track Health Care Management
Amsterdam Business School, University of Amsterdam
21
stof January, 2016
Lean Six Sigma improvement project at the
Preoperative Assessment Clinic at VU
University Medical Center
Author: dr. Katrin Stoecklein, MD, DESA
Anaesthesiologist, Pain Specialist, Head of Preoperative Assessment Clinic at VU University Medical Center
[email protected] UvA number: 10733612
MBA Supervisors: Prof. dr. J. de Mast, [email protected]
Prof. dr. R.J.M.M. Does, [email protected] dr. M. Schoonhoven, [email protected]
Abstract
Objective
Systematic preoperative assessment of all patients by the Preoperative Assessment
Clinic (PAC) of VU University Medical Center (VUMC) prior to surgery increases
patient safety and hospital cost-efficiency. This case study provides a thorough
analysis of the PAC processes and uses Lean Six Sigma (LSS) methodologies and
tools to streamline the workflows for a more satisfactory patient experience and to reduce costs.
Method
This study primarily used the Define, Measure, Analyse, Improve, and Control (DMAIC) approach to decrease waiting time (WT), processing time (PT), and administrative inefficiencies during PAC attendance.
Results
Approximately 50% of our improvement recommendations were implemented during this project. Total waiting time (WT TOTAL) decreased significantly by 20%. Total processing time (PT TOTAL) during the FOLLOW-UP measurements showed no significant decrease compared with Baseline measurements.
Conclusion
These first realized process improvements are promising. The LSS methodology contributed within the multidisciplinary LSS team to a thorough learning and understanding of the root causes of variation and waste within our processes. We expect further substantial beneficial financial results by the intended implementation of a new modus operandi, the ‘PAC carousel’, which will increase significantly the number of hospital admissions on day of surgery. Furthermore, the planned implementation of the new electronic patient record will significantly reduce administrative inefficiencies. The last two projects are part of our future implementation plan. The initiated process improvements will be continued.
Table of contents
I. Introduction 5
A. Preoperative Assessment Clinic (PAC)
II. Framing 12
A. Sense of urgency 12
B. Lean thinking 13
C. Six Sigma 14
D. Lean Six Sigma (LSS) 17
III. Case description 20
A. DMAIC: Define phase 20
A1. Project charter 20
A2. SIPOC 22
A3. Benefit analysis 24
A4. Stakeholder analysis 25
B. DMAIC: Measure phase 29
B1. Value stream map 29
B2. CTQ flowdown 31
B3. Operational definitions 32
B4. Measurement plan 32
B5. Validation of the measurements 33
C. DMAIC: Analyse phase 34
C1. Baseline measurements 34
C2. Gemba 36
C3. CTQs and influence factors 38
C3.1 Nuisance variables 38
C3.2 Control variables 40
C3.3 Disturbances 42
C4. CTQ Indirect time of the anaesthesiologists and residents 43
C5. CTQ Financial benefit 46
D. DMAIC: Improve phase 52
D1. Vital few 52
D2. Change Management 55
D3. The ideal future situation 56
E. DMAIC: Control phase 58
E1. FOLLOW-UP measurements 58
E2. Control plan 64
IV. Results 66
V. Conclusions 67
A. Further implementation of improvements, 67
including implementation plan for PAC carousel
B. Limitations of our LSS project 70
C. Future challenges of Healthcare and sustainability of LSS 71 in Healthcare
I.
Introduction
Increased awareness of patients, society, media and legislative institutions for patient safety, healthcare quality, cost explosion in the healthcare system and lack of customer orientation are forcing caregivers to rethink how they must manage their healthcare delivery systems (1). Experts in the field of economics claim that healthcare delivery systems, such as hospitals, must be able to provide high-quality care at reasonable costs (1). To establish significantly more efficient processes frequently references are made to the automotive industry, especially Toyota, enabling operational excellence by delivering high quality products for a reasonable price (2, 3). As a result, all stakeholders of the healthcare sector have recognised the signs of the time and declared the following three goals as crucial for the sector’s competitive survival: enhancing quality (for instance by reducing medical errors), improving timeliness, and reducing costs (4). In this context it is important to consider the core competence of a hospital. From operational management point of view, a hospital is a compilation of systems and processes within these systems, starting from a medical diagnose to a number of medical and non-medical processes during diagnostics and treatment (5). Obviously, a hospital is not an automobile manufacturer. However, whether an organization has to deal with processes at an industrial continuous working line or with medical processes during an appointment at an outpatient clinic: in both instances processes can be subjected to similar performance indicators defining operational effectiveness. Some examples from healthcare are listed below (6):
Quality of the ‘product’: e.g. expertise of the specialist, politeness to patients
Reliability: as little as possible medical errors, defects, incidents and as much as possible patient safety
Timeliness: e.g. regarding processing times of appointments at outpatient clinics, waiting times, access times for appointments
Flexibility: in case of variation of workload (e.g. too many patients without an appointment for only a few doctors), special requests of patients
Cost efficiency: efficient use of personnel, facilities and materials (man-hours, use of consultation rooms, use of expensive medical equipment, medication, etc.)
Every employee working in a hospital experiences several process inefficiencies per day: chasing for medical information (e.g. medication of a patient) creating delay upstream in the process, unnecessary interruptions of work-streams by inexperienced colleagues asking for information due to the lack of standard operating procedures, medical records that have to be moved, crowded waiting areas at outpatient clinics due to too few doctors, etc. These process inefficiencies – the so-called ‘hidden factory’ (7) - create substantial damage, e.g. medical errors, due to rushed and incorrect work, increasing number of complaints with associated time-consuming rework, etc. and substantial financial loss, e.g. loss of market share, revenue, etc. (7). The size of such a ‘hidden factory’, a factory, which is invisible on flowcharts and reports, increases the more the processes become more complex, for instance medical processes in hospitals. Organizations of other sectors, but also increasingly in the healthcare sector, have shown that solving these issues by reactive firefighting methods does not create sustained success. This is because of the fact that all these recurring process issues suffer from the same systematic problems and root causes, respectively (5). Implementing the Lean Six Sigma (LSS) framework via LSS improvement projects enables organizations to achieve operational effectiveness (like Toyota) by realizing Lean processes; processes, without defects and disturbances, without waste (e.g. chasing for information, rework), timely, smoothly performed and meeting all the customer demands (8). This is an idealized sketch, of course. But by focusing on and analysing the processes, diagnosing the root causes and learning the LSS standard methodologies and tools especially employees from the middle management are able to come a bit closer to operational excellence (9). Therefore LSS is considered as a framework for continuous process improvement activities.
A. Preoperative Assessment Clinic (PAC)
Preparing a patient for anaesthesia and surgery is also a complex medical process and requires an understanding of the patient’s preoperative status, the nature of the surgery and the anaesthetic techniques required for surgery, as well as the risks that a particular patient may face during this ‘perioperative’ time (10).
In the past two decades the number of surgical procedures performed to a growing elderly population with two or more co-existing chronic diseases has grown in European countries (11, 12). Advances in medical technologies regarding therapy of chronic diseases, less invasive surgical interventions, improved anaesthesiology with advanced monitoring enabled this development (13, 14). These innovations have also improved patient safety and health outcomes for patients with compromised health status, and have in many cases reduced the cost per intervention by shortening the length of stay (LOS) in hospitals (15-21). Anaesthesiologists at
Preoperative Assessment Clinics (PAC) are in an unique position since they oversee
the total perioperative trajectory and develop an individualized perioperative risk profile based on the nature of the surgery and existing chronic diseases. These co-existing chronic diseases of mainly elderly patients above 65 years of age require careful assessment and perioperative coordination (22, 23). Systematic preoperative anaesthetic assessment of all patients scheduled for elective surgery accomplishes following purposes (24, 25):
Decrease cancellations on the day of surgery
Increase the likelihood of admission on the day of the procedure and of early discharge
Improve the patient’s experience of their hospital admission
Ensure that patients understand their procedure and are well informed
Increase patient safety by reducing complication rates, mortality and creating the best chance of good post-operative recovery.
Routinely, anaesthesiologists use a grading system to evaluate the degree of a patient's ‘level of sickness’ and ‘physical state’ before selecting the anaesthetics for surgery. Describing patients' preoperative physical status is used for recordkeeping, for communicating between colleagues, and to create a uniform system for statistical analysis (26). The American Society of Anesthesiologists (Table I) initially created the American Society of Anesthesiologists (ASA) Physical Status (PS) classification system in 1941 (27).
Table I. ASA Physical Status (PS) Classification System from the American Society of Anesthesiologists (ASA).
The PAC is one of the busiest outpatient clinics at VUMC. Patients from sixteen different medical specialties attend the PAC. Patient attendances with a complex medical condition – ASA category 3 and 4 - at the PAC had increased over the past 5 years. In contrast, however, the total number of patients who attended the PAC even gradually decreased from around 10.000 per year to about 9.000 patients per year in 2014 with no noticeable beneficial effect on processing time (PT) and waiting time (WT). The PAC waiting room kept busy and crowded with more than 50% of all patients waiting longer than 30 minutes. Furthermore, not all patients who visited the PAC could be seen on the day of attendance, resulting in an unnecessary journey to the hospital or enormous long WT.
The doctors, performing the preoperative assessments, and the nurses, performing the cardiopulmonary measurements, work in individual consultation rooms. Patients move between these rooms and often have WT in between. Administrative workload and extensive rework increased per case due to an increase in patient’s medical complexity, which results in longer anaesthesiologist consultation time.
Further identified time consuming factors in this context were: the need for obtaining case notes from other specialists from outside the hospital, missing list of medication, missing anticoagulation advice by surgeon, etc. As a result of these obvious administrative inefficiencies, PAC secretaries reported feeling very busy and were worried about their capacity to deal with an expected further increase in administrative workload due to increasing legislative documentation requirements. Patients were also asked semi-annually to describe the service at the PAC, and many used terms such as "busy" and "too long waiting times". Previous studies have shown that patient satisfaction is strongly correlated with the time spent at the outpatient clinic; especially WT are a common cause of dissatisfaction (28, 29).
Benchmarking with other PACs at academic hospitals in the Netherlands, best practice medical guidelines and changed stricter legal safety standards from the Dutch Healthcare Inspectorate (IGZ) made it necessary to re-design our PAC processes completely. Supported by a VUMC innovation budget, the mandatory routine interview with a pharmacist for patient’s medication verification and with a nurse about all relevant medical issues and medical history on day of admission will be moved to the PAC in January 2016. As a result, the preoperative admission day prior to surgery can be saved systematically. Previous research has shown that performing the preoperative assessment at the PAC can improve cost-efficiency of hospitals significantly (16-21). The order of steps within this new PAC process design, first the medication verification by the pharmacy-assistant, followed by a basic medical interview by the nurse and finally the specialized preoperative assessment by the anaesthesiologist – called ‘PAC carousel’ – can significantly contribute to more efficient use of hospital beds (Figure 1). Further, the consultation time by the anaesthesiologist will be shortened due to the fact that several medical topics, i.e. medication, medical history, etc. have been already solved by the pharmacist and by the nurse. In an earlier stage of our change management journey we identified the consultations performed by the anaesthesiologist as bottlenecks in our healthcare delivery chain. This expected shortening of the consultation time would be beneficial for the total PT at the PAC.
Figure 1. PAC carousel: The appointment cycle a patient must attend before receiving PAC approval prior to surgery. Routine medical interviews by nurse and pharmacy-assistant on day of admission will be transferred from inpatient-clinic to PAC-outpatient-clinic, performed during preoperative trajectory. By integrating these two formerly inpatient interviews within the current PAC process the proposed PAC carousel will be complete.
The chosen pilot department was the department of General Surgery, a department with about 1920 surgeries and associated admissions in 2014. The department of General Surgery and the department of Anaesthesiology are part of Division 4 within VU University Medical Center (VUMC). Division 4 also includes department of Cardiothoracic Surgery, Cardiology, Orthopaedic Surgery, Urology, Intensive Care Units, and Emergency Department. With these major players, Division 4 generates the highest revenues in comparison with the other divisions (Division 1, 2, and 3). Given the fact that the VUMC as academic hospital is specialized in intensive and complex care, in the form of tertiary clinical care and as tertiary referral-center, it serves a large geographical area.
Basic items and medical history by nurse Consulta on by anaesthesiologist PAC CHECK OUT PAC CHECK IN Verifica on of medica on by pharmacy-assistent
Moving from Clinic to Outpa ent Clinic (OPC)
PAC carousel
Moving from Clinic to OPCMore than half of all patients are from outside the Greater Amsterdam area. In addition, VUMC is an urban and regional hospital, which provides regular, specialist care to the inhabitants of its service area (30).
Our LSS project was initiated as part of a large-scale preoperative trajectory improvement project – from the appointment at the surgeon to the operating theatre door - to improve operational effectiveness and reducing costs during the preoperative trajectory. The specific objectives of this LSS improvement project were:
Decrease WT of PT at the PAC
Decrease of administrative inefficiencies (‘waste’) at the PAC
Shortening of length of stay (LOS) by admission on day of surgery.
We utilized LSS methodologies and tools in order to accomplish these goals. Specifically the primary methodology of Six Sigma – the DMAIC cycle – is often applied by business organizations to reduce effectively the variability and waste within the processes inhibiting systematically such goals (5, 31).
II. Framing
A. Sense of urgency
The healthcare sector and its current challenges, such as submitting to the laws of the market with rising competition, stricter legislation and multiple sources of cost explosion due to an aging society and expensive disruptive technologies are making regularly the headlines. Knowledge about these complex developments in various fields has evolved in many ways, but nevertheless the healthcare sector is still searching for the Holy Grail. There is increasing recognition, supported by growing evidence, amongst experts in the field of operational supply chain management, that the issues of healthcare delivery systems may require healthcare sector specific unique approaches, methodologies and tools (32).
The lack of operational effectiveness, let alone operational excellence, within healthcare institutions costs since several years both, lives and money. The following list ‘highlights’ some published cases, which demonstrates the link between lack of operational coordination (not the right people in the right place at the right time with the right equipment) and financial loss:
Significant number of delayed starts of surgeries in operating rooms (OR) due to process variation, e.g. nurse’s time-consuming search for the right equipment, resulting in exceeding OR schedules and cancelling of planned surgeries at the end of the day (33).
Spending significant man-hours per nurse shift for searching for supplies (34). These are man-hours, which were lacking at the value adding processes, e.g. bedside care by the nurse.
Medical errors causing deaths and significant increase of hospital costs due to longer admissions or re-admissions (35).
Error rates in Pathology laboratories of over 7% due to mislabelling and other process related mistakes (36).
These studies indicate that managers in healthcare institutions, together with healthcare professionals, should develop an overarching strategic approach in order to reduce process variation by organizing adequately the several components of these healthcare delivery chains, e.g. patients, staff, equipment and supplies.
B. Lean thinking
Evidently, every preoperative assessment is a medical process, which consists of a series of steps. Thus, this path taking the patients through our PAC – also in the most literal sense – can be examined and improved. Lean thinking can be described as “an integrated system of principles, practices, tools, and techniques focused on reducing waste, synchronizing work flows, and managing variability in production
flows” (31). The Toyota Lean Production System have taught us that by investigating
these steps within the processes value from the patient’s point of view can be identified and organizations can get rid of waste that obstruct workflow within these processes (31, 37).
The Lean Manufacturing method originates from Taiichi Ohno’s Toyota Production System (TPS), which is closely related to the Just-In-Time (JIT) principles (38). Lean is essentially aimed at the reduction of waste and inefficiencies within processes across the entire supply chain, and is focused on those activities that increase the quality and value of the product for the customer. The Lean framework is based on five organizing principles (3):
Value: as perceived by the customer
Value stream: all processes involved delivering value to the customer
Flow: efficient functioning of the value stream
Pull: the system responds to customer demand so as not to build up inventory
Perfection: elimination of waste
Elimination of waste is critical to the success of Lean thinking and three types of waste – in Japanese terms muda, muri, mura - are identified, which inhibit the flow of work (39):
Muda: non value adding activities
Muri: overuse of staff, systems of equipment
Mura: unplanned variations in a process
Focusing on waste elimination and improvement in workflow, every activity can add value for the customer and can reduce operational costs. Since 1980s Lean operational tools and principles has been used across many different sectors (40, 41), including healthcare management in the last 10 years (42). However Lean thinking includes not only operational tools but also the development of a ‘quality culture’, which eventually can lead to a change of people by adopting Lean principles (43, 44). It can be regarded as an interaction between people and the Lean efficiency tools (e.g. value stream map, visual management, etc.). In adopting Lean practice by removing waste, which obstructs workflow, Lean philosophy can change processes
and can let employees also go through a process of change (43, 44). Floor personnel
with a continuous strive for quality, empowered to raise awareness for quality issues and also empowered to implement improvements based on their floor-specific knowledge and skills can significantly make the difference by creating quality culture at their workplace day after day. Lean thinking facilitates this continuous improvement, known as Kaizen (45). Indeed, this bottom-up approach promotes participation and cooperation of floor personnel by changing behaviour and mind-set. However, the limits of Kaizen are reached when key issues with conflicting stakeholders’ views must be solved, resulting in skirting around ‘sacred cows’. This is then the time to add top-down approach via an external adviser and overarching decision-makers in order to denounce, where necessary, uncomfortable truths and implement a holistic strategy, which is certainly the case facing quality issues.
C. Six Sigma
In comparison to Lean thinking with its comprehensive viewpoint and its focus on collaborative behavioural structures, Six Sigma promotes a more top-down scientific approach by studying and analysing data empirically and experimentally in order to reduce variation, to measure defects, and to improve the quality of products, processes, and services (46).
The concept of Six Sigma was developed in the early 1980s at Motorola Corporation and further evolved in the late 1990s by General Electric Corporation (47). From very practical point of view floor personnel get equipped with a wide array of quality problem solving tools. The use of these tools varies based on the type of process studied and the problems that are encountered (48).
The guiding principles of the Six Sigma methodology are (5):
Searching for the genuine causal factors of a system’s problem
Translating targets into tangible measurable objectives, the so-called Critical
To Quality topics (CTQs), e.g. percentage decrease of surgery cancellations,
percentage decrease of patients waiting longer than 30 minutes in outpatient clinic
Quantification of the problem, e.g. financial loss, waste of man-hours
Data based diagnosis: determination of the vital few, which will make the difference regarding improvement performance.
Data based testing of improvement plans: by brainstorming, feedback, experimentally testing, fine-tuning
This mentioned general principles of Six Sigma were translated into an improvement action plan, which helps floor personnel to structure the problem, creating a roadmap with foreseeable manageable objectives, and common fixed points of delivery, the so-called DMAIC cycle (49, 50), Table II. The Six Sigma DMAIC problem solving methodology is used to improve processes.
Table II. Reconstruction of the DMAIC cycle, according to De Koning en De Mast (51).
The phases of the DMAIC are well-defined and standardized, but the steps performed in each phase can vary based on the reference used. The Define phase is where the scope of the project charter is developed. The goal of the Measure phase is to understand and baseline the current process. In the Analyse phase, we analyse the data collected in the Measure phase to identify the root causes of the problems identified. In the Improve phase, the improvement recommendations are developed and implemented. The goal of the Control phase is to ensure that the improvements had a positive impact and that they will be sustained and controlled.
The Six Sigma framework has been applied in a number of cases in the healthcare sector. Here are some published cases, documenting beneficial effects after implementation of Six Sigma methodology:
Greater efficiency and reduced delays in hospitals in California (52).
Reduction of medication errors at the Alton Memorial hospital, Illinois (53).
Decrease of errors in diagnosis and treatment of childhood strokes (54).
Improving patient care, business processes and outcomes at the Mt. Sinai Medical Center (55).
D. Lean Six Sigma (LSS)
Given the fact that Lean and Six Sigma have the same general purpose, providing the customer with the best possible quality, reducing variation, and eliminating waste,
a combination of both, Lean Six Sigma (= LSS), amplifies the strengths and
minimizes the weaknesses of both approaches when used alone (31). Six Sigma is a quality management methodology that focuses on reducing variation, measuring defects (per million output/opportunities), and improving the quality of products, processes, and services (51). The concept of Six Sigma have its roots in Walter Shewhart’s concepts of control charts and statistical process control (57), which gained further success as part of Total Quality Management in the 1970s and evolved further to Six Sigma (58). In parallel with these developments the earlier mentioned Toyota Productions System with Just-in-time production evolved into Lean thinking (59, 60). A merger of Lean and Six Sigma combines the best of both improvement philosophies and methodologies in a complementary way (31).
De Koning et al. (31) defined following guiding principles of LSS:
Structured approach: Hierarchical organization of improvement specialists, i.e.
Six Sigma specialists (Black Belts, Green Belts, and Champions), who are implemented into the existing human infrastructure.
Project-based deployment
Competency training: LSS project leaders are systematically trained in Six
Sigma with additional Lean components.
Organizational embedding of solutions: with clear definitions of responsibilities
and implementation of standard procedures and process controls
Alignment with organization’s strategy: “Strategic objectives are translated into
performance indicators and tactical goals. These are then used as a basis for project selection and help secure an alignment of projects with the overall organizational strategy” (31).
However, implementation of LSS is not an automatism associated with guaranteed success. The LSS framework must be aligned with an organization’s strategy (61), whereby LSS projects can help to guide the organization into the right strategic direction and to translate beneficial results of a LSS project into strategic financial
strive for innovation, their flexibility to adapt quickly in new circumstances and their ability to exploit new opportunities are the ingredients of their secret for success (62). On the one hand the need of organizations to constantly develop and maintain such vital core competences, and on the other hand the LSS methodology, which offers the Kaizen philosophy combined with organizational hierarchic structures and scientific tools to realize improvement plans; it seems to be the perfect match (5). Furthermore, the ability of an organization to relentlessly strive for quality and innovativeness could by means of LSS grow into an independent competitive advantage. All the more, because of the LSS guiding principle to empower and, also in a very practical sense, to equip the employees with adequate capabilities and skills in order to foster a culture, which promotes a culture of continuous improvement. These skilled employees and such a culture could also form a competitive advantage, which makes an organization an appealing employer (63).
Some interesting published cases are listed below, documenting beneficial effects after implementation of LSS methodology:
Development of a clinical pathway for hip fractures, associated with decrease of
average duration of surgery and LOS (64).
Shortening the LOS in chronic obstructive pulmonary disease patients, reducing
the number of patients requiring intravenous antibiotics, shortening the preparation time of intravenous medication, reducing the number of mistakes in invoices, etc. in a Dutch hospital (65, 66, 67).
Reducing overuse of diagnostic tests for trauma patients, associated with
improved quality of care (68).
We as a LSS project team experienced that the tools of Six Sigma provided us with a sort of compass or roadmap, which guided us quite literally through our project. The Lean principles and the Kaizen philosophy determined our behaviour and mind-set. Lean tools helped us to eliminate waste, organize, and simplify the work processes. The DMAIC cycle within Six Sigma gave us a problem solving approach, combined with a wide array of quality problem solving tools. Use of these tools varied based on the type of process studied and the problems that we encountered. The fact, that both frameworks are closely interwoven, could be for instance seen in the DMAIC Measure phase, which uses the value stream map as Lean tool, or the Lean
III.
Case description
A. DMAIC: Define phase
If we employ LSS we have to delineate the problem in the Define phase, i.e. define
the scope and process to be improved. To achieve this, we selected a LSS team with capable members, launched, and communicated the project. The LSS project team of the PAC drafted a Project charter that includes a cost-benefit analysis, which met our established financial thresholds and were as a result accepted by the project
Champion. The following steps were: SIPOC analysis, Benefit analysis, including
CTQs (= Critical to Quality), and Stakeholder analysis.
A1. Project charter
This project is focused on streamlining the preoperative assessment processes prior to elective surgery. This includes gathering all relevant information regarding patient’s preoperative status and explaining the nature of the surgery, the anaesthetic techniques required for surgery, as well as the risks that a particular patient may face during this perioperative trajectory. The goals of this project are to identify process inefficiencies and improvement recommendations that can reduce PT and WT, reduce administrative waste and enable admissions on day of surgery. Table III contains a summary of our Project carter. There could be an improvement in patient satisfaction and quality of care due to the synergistic relationship between PT, quality, and satisfaction. The scope includes an assessment of the PAC and its processes starting from patient arrival, triage, consultation, to finally PAC approval. This project also included identifying the major constraints to PT and developing a new process design with improvement recommendations. Projected Financial Benefits include increased volume through improved performance and reduced costs through improved efficiency (time per patient). Out of the scope of this project were processes at the Operating Room (OR), Recovery Room, surgical inpatient wards and at surgical outpatient clinics, Table IV.
Table III.
Table IV.
7
Project details
Type of project
DMAIC Improve current process/product
Deliverables
Implementation of the solution
Side conditions
Support and commitment from head of Anesthesiologie and nursing director For realization of PAC carousel system: provide with personnel, rooms and time
In scope Out of scope
Preoperative assessment process Processes at Operating Room
Processes in postoperative trajectory Processes at surgical outpatient clinics
Describe possible earlier improvement attempts
Lack of a comprehensive approach, including all stakeholders Commitment
Contingencies / complications / worst case scenario
Sense of urgency by the surgeons: several meetings are planned with surgeons and patient participation group members in order to illustrate this problem. Win-win through planning certainty, increase of patient safety, especially for high-complex cases.
2
Project charter: summary
Project title:
Implementation of PAC carousel at Preoperative Assessment Clinic (PAC) at VU University Medical Center
Process or product to be improved:
The preoperative screening process at PAC
Objective of the project:
1) Decrease of waiting time (WT): Objective: WT of 80% of walk-in patients (= without PAC appointment) ≤ 30 minutes
2) Admission on day of surgery: Saving 500 preoperative Length of Stay (LOS) days
3) Decrease administrative inefficiency
Anticipated benefits:
376.649 Euro / year
Start date: Anticipated completion date:
June 2015 November 2015
Black belt Green belt(s)
Katrin Stoecklein None
Approvals
Black belt: Medical head of PAC
Green belt: None
Supplier: Head of Anaesthesiology
(responsible for time of BB / GB)
Champion: Nursing director division 4
(problem owner)
User: Nursing director division 4
(needed for benefit realisation)
Table V.
We attained sponsorship by the decision-makers within our Division 4, in particular the head of Anaesthesiology and General Surgery, respectively, and by the Chief Nursing Officer and CFO of Division 4 and constituted a capable team consisting of the medical head of the PAC and a senior and junior PAC secretary (Table V).
A2. SIPOC
Figure 2. SIPOC = Suppliers, Inputs, Process, Outputs and Customers
The classic LSS tool called SIPOC (Figure 2), which stands for Suppliers, Inputs, Process, Outputs and Customers, helped us to get a bird’s eye view of the process, to scope the problem and to pinpoint what and where to measure. The SIPOC is used to ensure that the scope of the project is well understood. It is also a check and balance for the customer and stakeholder analysis.
6
Project organisation
Supplier Champion User MBB
Head of Anaesthesiology Nursing director division 4 Nursing director division 4 Supervisors Amsterdam
Business School (the person supplying resources such
as time and budget)
(the person who owns the problem) (the person who reaps the benefits from the project)
(experts in Lean Six Sigma methodology)
Black belt Green belt Green belt Green belt
Medical head of PAC None None None
Investment in time (hrs./week) Investment in time (hrs./week) Investment in time (hrs./week) Investment in time (hrs./week) 12
Team members (hrs/week) Senior secretary PAC: 4 hrs/week Junior secretary PAC: 8 hrs/week 2 x Lean coaches: 2 x 8 hrs/week
3
SIPOC
Suppliers Inputs Process Outputs Customers
Surgeon Surgical referral PAC consultation by
anaesthesiologist
PAC approval: yes or no Patients Personnel Division IV Board of directors Step 1 Check-in at PAC front desk Step 2 by indication Cardio-pulmonary measurements = CPM’s: ECG, oxygen saturation, lung function Step 3 PAC consultation by anaesthesiologist Step 5 PAC Rework: pending findings have arrived Step 4: by indication • Blood work • Referral to other specialists • Request of case notes of specialists outside VUMC
Our customers and suppliers - patients, personnel, employees of our division, board members – are also identified as project stakeholders.
The secretary at the PAC check-in front desk reviews the completed PAC questionnaire and the surgical request in the OR information system and decides based on medical triage criteria if the patient needs cardiopulmonary measurements (CPM) first prior to the consultation by the anaesthesiologist, which include blood pressure, electrocardiogram (ECG), lung function testing, height and weight. All medical files were then sorted in file racks based on type of PAC appointment (walk-in vs. fixed appo(walk-intment) and type of surgery (low, (walk-intermediate or high risk surgery).
The medical team of the PAC consists of a staff anaesthesiologist and a senior and junior resident. The senior resident assesses the patients with an appointment, whereas the staff anaesthesiologist assesses the patients scheduled for intermediate or high-risk surgery. The junior resident mainly assesses minor complex walk-in patients.
If indicated on medical reasons (co-existing chronic diseases, international preoperative assessment guidelines, best medical practice) additional examinations are requested, i.e. blood work, referral to other specialists or request for case notes of other specialists outside VUMC. On arrival of these requested findings these medical files without a mandatory PAC approval are reviewed again for final approval.
2.4 Benefit analysis
Table VI.
The ‘benefit analysis’, including the financial benefits, produced the following results (Table VI):
1. Increase of patient satisfaction by reducing WT
2. Saving of 199.149 Euro of hourly wages yearly by increase of administrative workflow efficiency
3. Saving of 177.500 Euro yearly by admission on day of surgery
5
Benefit analysis
Characteristics to be improved (CTQs) Current performance 2014 - 2015
1) Decrease of waiting time (WT) WT of > 50% of walk-in patients (= without PAC appointment) ≥ 30 min 2) Admission on day of surgery Low percentage of General Surgery patients who arrives at day of surgery. 3) Decrease of processing time of
consultation by anaesthesiologist
Missing list of medication: 2857 patients (31,7% annually) x 15 min. = 714,25 hours x 25 Euro hourly secretary wage = 17.856 Euro Missing anticoagulation-advice by surgeon: 2162 patients (24% annually) x 15 min = 540,5 hours x 85 Euro hourly specialist wage = 45.943 Euro
Missing surgical referral: 1884 patients (20,9% annually) x 10 min. = 314 hours x 25 Euro hourly secretary wage = 7850 Euro Typing from paper to digital file: 9000 patients annually x 10 min = 1500 hours x 85 Euro hourly specialist wage = 127.500 Euro Total of administrative waste = 199.149 Euro
Benefits of the project for the customer
Increase of patient satisfaction Increase of efficiency
Benefits for the business
Saving 500 hospitalization days = 500 x 355 Euro = 177.500 Euro
Anticipated investments
Implementation of PAC carousel system: 3 x nurses: 90.000 Euro/year
Accounting-wise no extra costs: 1 x pharmacist-assistant: 0 euro + 2 x PAC examination rooms (0 Euro)
Medical PAC staff:
1) 1 x anaesthesiologist (200.000 Euro / year) 2) 2 x residents: 1 x junior, 1 x senior (0 Euro / year)
Pool of 25 x anaesthesiologists and 50 x residents: According to personnel scheduling each day a different medical team works at the PAC. The medical team composition is every day the same, consisting of 1 x anaesthesiologist, 1 x advanced senior resident and 1 x junior resident, during lunch time accompanied by a 3rd resident. Real personnel expense is only the anaesthesiologist, accounting-wise all residents are a surplus, no personnel expenses at all.
Working hours of anaesthesiologist: 8 a.m. – 5:30 p.m. = 9 hours Administrative PAC secretary staff:
1) 1 x front desk employee 2) 1 x PAC back-office employee
3) 1 x employee for CPM‘s (= cardio-pulmonary measurements) = 3 x 20.000 Euro / year
Working hours of administrative PAC staff: 8 a.m. – 4:30 p.m. = 8 hours
Hard benefits (=direct bottom-line monetary savings)
Saving 500 hospital days x 355 Euro / year = 177.500 Euro Saving 199.149 Euro wages by removal of administrative waste
Soft benefits (=risk avoidance and nonmonetary benefits)
Increase reputation Increase efficiency
Strategic benefits (=the project is an enabler)
Leading position in the field of the organization of a PAC Realisation of best practice guidelines
2.5 Stakeholder analysis
Table VII. The table ‘Stakeholder analysis’ is not on display due to confidentiality
reasons.
The stakeholder’s analysis identifies the stakeholder groups, their role and how they are impacted, as well as their concerns related to the process. The influence column provides a quick overview whether the impact is positive (+, ++), such as facilitate with resources, or negative (-, --), such as resistance to change. Our next step in the
stakeholder analysis was to understand the stakeholders’ attitudes towards change,
as well as potential reasons for resistance. Additionally, the team developed a better understanding of barriers to change as a result of resistance. Next, activities, plans and actions were developed that helped us to overcome the resistance and barriers to change. A definition how and when each stakeholder group should participate in the change effort were developed and updated constantly throughout the DMAIC project. The stakeholder commitment scale (green coloured columns) was used to summarize where the stakeholders have positioned themselves regarding their acceptance or resistance to change. The team determined, based on initial interviews and prior knowledge of the stakeholder groups, the current level of support or resistance to the project. Strongly supportive (++) indicates that these stakeholders are supportive and help to realize change. Moderately supportive (+) indicates that the stakeholders will help, but will not be strongly involved. The neutral stakeholders (0) will allow the change but will not proactively advocate the change. Moderately against (-) stakeholders do not comply with the change, and have some resistance to the project. Strongly against stakeholders (--) will not comply with the change and will actively and vocally lobby against the change. Strategies to move the stakeholders from the current state to where the team needs them to be by the end of the project were developed and constantly adjusted throughout the DMAIC project. The stakeholders are the patients, the heads of Anaesthesiology and General Surgery, Chief Nursing Director of Division 4, head of personnel of whole outpatient clinic, secretaries of PAC, surgeons, anaesthesiologists, surgical planners and nurses and pharmacy assistants from the clinic. Before implementation of the PAC carousel, the surgeons sent patients scheduled for surgery directly to the PAC without any appointment.
Previous resource utilization measurements revealed that this immediate-walk-in pattern causes significant workflow disturbances and variation of workflow resulting in extremely rising PT and WT in peak hours (especially between 11 a.m. to 2 p.m.) and peak days (especially on Wednesday and Thursday). The PAC carousel system, which will be implemented in January 2016, must create a prioritisation of patients based on surgical urgency (Figure 3):
Surgery scheduled within 4 weeks: patient can walk-in immediately
Surgery scheduled longer than 4 weeks later: patient will get a fixed PAC
appointment 4 to at least 2 weeks prior to surgery
Every patient already having medical file in PAC database: can be scheduled
for consultation by phone
Figure 3. PAC carousel: Prioritisation of patients based on surgical urgency.
Surgeons were concerned about that some patients have to attend at a second time for their preoperative assessment. According to the surgeons, this concept of immediate walk-in at the PAC is very patient friendly and has a potential competitive advantage to other academic healthcare providers. However, the negative consequences are extremely long WT, up to even 3 hours, and poor results regarding patient satisfaction and Netto-Promotor-Score, which is an important recommendation indicator. During several talks at surgical departments members of the executive management team of the PAC explained the benefits of the PAC carousel and made compromises for instance for special patient categories.
The work of the surgical planners at the surgical planning bureau is characterized partly by medium-term-planning, but also to a significant extent by ad hoc planning due to a shortage of operating time at the OR, changing schedules of surgeons, etc. The prioritization system of the PAC carousel reduces the pool of patients, who have already PAC approval, and who are used to fill in the OR gaps. Furthermore, it requires more extensive and more controlled planning for patients whose surgery is scheduled longer than four weeks and who needs a PAC appointment at least two weeks prior to surgery. However, results of our incident database revealed that the latency between PAC consultation and the day of surgery were frequently too long, resulting in loss of relevant information by the patient, regarding e.g. discontinuation of medication prior to surgery or fasting guidelines. This can significantly compromise patient safety and can lead to surgery cancellations.
During this project patient representatives (Figure 4) were integral part of the LSS team. By sharing their first-hand experiences and emphasizing the importance of patient-centred solutions they generated valued “aha” effects beyond plausible logical explanations. After several interviews and brainstorm sessions all concerns of the group of planners were addressed and led to a modified version of the workflow. Figure 4. Brainstorm session with LSS team.
The secretaries of the PAC and anaesthesiologists were concerned about potential delays when performing these triple appointments (pharmacy assistant nurse anaesthesiologists) of the PAC carousel, potentially leading to synchronization problems between appointments. Best-practice knowledge from other academic PACs regarding setting up of an integrated triple appointment system was key for establishing baseline knowledge prior to the go-live period.
Implementation of this PAC carousel is associated with two new healthcare professional groups within the preoperative healthcare delivery process, entering the PAC floor: nurses and pharmacy assistants. Taking benefit of the annual innovation budget distribution within Division 4 and thereby meeting the current cost-neutral human resource strategy temporarily solved the financing issue of the PAC carousel. Further analysis has to show if these investments pay off by for instance saving hospitalization days in the clinic. Furthermore, the decision-makers of Division 4 have
concerns regarding the outpatient clinic’s productivity goals. There is great
consensus to further streamline the processes, so that in the future the more work due to PAC carousel could be done with the same number of people.
B.
DMAIC: Measure phase
B1. Value stream map
Figure 5. Value stream map.
In the subsequent Measure phase we developed a value stream map (Figure 5), which provides a systems view of the departments and functions involved in preparing the patient for surgery. It shows the requirements for each function, the delays, wastes (Table VIII) and opportunities for improvement in the value stream. By understanding the process from the start to the end and the hand-offs between each function, we can better streamline the entire process that the patient is experiencing. Our value stream map shows the more detailed activities that are performed in the PAC. The process is lengthy, with much redundancy and “touching” of the file by many people multiple times throughout the process.
Surgical Outpa ent Clinic (SOC)
Pa ent PAC front desk:
Secretary and NA (= nurse assistant) CPM =
cardiopulmonary measurements Anaesthesiologist (ANS) With completed PAC ques onnaire With list of medica on Reading file in consulta on room: T = 3 min. Pick-up pa ent PAC consulta on of pa ent T = 17 min. Pick up medical record from front desk
With medical file on paper Transfer to wai ng hall: T = 32 min. Surgeon completes electronic SURGERY REQUEST in CHIPSOFT Pa ent goes to PAC 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 I I NA executes CPM*: T = 3 min.
NA: pick up pa ent
ANS completes electronic PAC record T = 4 min. Y N
Transfer to wai ng hall:
T = 5,6 min. N Y NA places CPM results in Mirador PAC approval NA places CPM results in Mirador and shows ANS Y 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 CPM okay? Y N I I CHECK-IN + Triage: T = 3,6 min.
PAC front desk:
Secretary Lab? At other outpa ent clinic 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 Other specialist examina on ? At other outpa ent clinic Results from other hospital? 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 I I ANS Re-evalua on of PAC T = 10 min. Pending fin d i ng s arrived Waste WasteWaste Waste Other findings pending? Nurse helps pa ent to complete PAC ques onnaire on paper I I Surgery request in CHIPSOFT ? Call to surgical SOC N Pa ent completes at PAC N PAC ques onnaire complete ? Y CPM*? CPM? PAC approval Y
Table VIII. Explanation of the red symbols, pictured in the value stream map (Figure 5), representing the seven forms of waste.
Inventory: Work in progress, which is not having value, added to it. Motion: Unnecessary movement of people, parts or machines within a process.
Transportation: Unnecessary movement of parts between processes. Waiting: People or parts that wait for a work cycle to be completed. Complexity: Processing beyond the standard required by the customer
Rework: Non-right first time. Repetition or correction of a process.
Efforts caused by rework, scrap and incorrect information.
The red symbols within the value stream map (Figure 5) identify opportunities for improvement in the value stream as follows:
Changing current ratio walk-in vs. appointment of 80% : 20% by increasing the
number of appointments.
Present medical files on paper are not meeting the needs of permanent data
availability and timely data entry. The files are touched, worked on, reviewed and transported multiple times throughout the process. There are few visual controls that provide the status of the charts moving through the process. In a few months, the hospital-wide implementation of a new electronic medical record will significantly facilitate healthcare delivery.
The anaesthesiologists are the bottlenecks resulting in significant WT. Less
WT occurred before start of cardiopulmonary measurements by the nurses. Waste WasteWaste Waste 765 12 11 10 8 4 2 1 9 3 765 12 11 10 8 4 2 1 9 3 I I
There is a significant correlation between complexity of patients, expressed in higher ASA classification 3 or 4, and length of PT. With growing number of co-morbidities and increasing frailty health condition significant more medical issues relevant for the perioperative trajectory have to be tackled and solved preoperatively, thus extending significantly the PT at the PAC, the more when interdisciplinary issues like perioperative anticoagulation strategy left open by surgeons with subsequent corrections by anaesthesiologists later in the process or when the patient’s medication list is absent.
About 20% of all PAC cases cannot be provided with an immediate PAC
approval on day of attendance due to need for other findings, i.e. lab-work, referral to other specialist, request for case notes of other specialist outside VUMC, etc. On arrival of these requested findings, very likely a different anaesthesiologist reviews the case again, which could create information discontinuity with all associated safety consequences.
The arrived amount of requested medical information from elsewhere exceeds
routinely the amount, which is relevant for PAC approval.
B2. CTQ flowdown
Figure 6. CTQ flowdown.
During brainstorm sessions of all stakeholders strategic focal points were defined, project objectives were identified and translated into CTQ’s, including WT, PT, indirect time and financial benefit.
Patient satisfaction Processing time Strategic focal points Throughput time Waiting time Project objectives CTQ CTQ flow down Operational costs Personnel costs Indirect time Preoperative LOS days Financial benefit Administrative costs
B3. Operational definitions
Table IX. Operational definitions.
The operational definitions were developed for each metric.
B4. Measurement plan
Table X.
Unit Per patient
Measurement
procedure Travel sheet
Goal PT: as little as possible WT: 30 min Per employee per day Timesheet As small as possible Waiting time/
processing time Indirect time
CTQ / constituent Operational definitions Per activity per patient Travel sheet As small as possible Administrative time General Surgery patients Business intelligence data VUMC As small as possible Preoperative hospitalization days CTQ Measurement Procedure Unit: per what? Per job? Per request? Per hour? Per day? Sample size Who will collect the data?
When? How will the
data be analysed / displayed?
Processing time and waiting time
Travel sheet Per patient Baseline 166
Follow-up 77 Employees Week 26+27, Week 47+48 Histogram, Basic Statistics, Value stream map
Indirect time Time sheet Employee per
morning, Employee per afternoon 1 x anaesthesiologist 2 x residents Tues to Thurs 2 weeks 12 days Employees Week 26+27, Week 47+48 Cake diagram Administrative time
Travel sheet Activity per
patient Baseline 166 Follow-up 77 Employees Week 26+27 Preoperative LOS days Business intelligence data VUMC General Surgery patients population Employees Year 2014
Measurement plan
We conducted our measurement plan by observing WT, PT, administrative time and cycle times (the times for each individual part of the process) by means of travel sheets, which followed the path of the patient during the whole visit at the PAC. Observations of direct (= patient related) and indirect (= not patient related) activities of the anaesthesiologists and residents were conducted by digital time sheets. Previous measurements showed an almost 90% utilization rate of the PAC secretary personnel due to their dual work obligations divided between PAC and the Pain Outpatient Clinic resulting in the conclusion to exclude measuring their activities. A data query extracted from VUMC business intelligence data network revealed that the majority of the General Surgery patient population (1920 admissions in 2014) is admitted 1 day prior to surgery. According to our cost-benefit analysis much workflow efficiency and real savings could be gained by designing the preoperative assessment processes in such a way that we could save 500 hospitalization days through admission on day of surgery.
B5. Validation of the measurements
We validated the measurements by ensuring that the PAC personnel are capturing the correct data, that the cases were complete, that the data reflects what is happening process wise and we were able to assess a change in the process with our measurements as well as a potential measurement error. We ensured that the measurement system was stable over time with regard to repeatability and reproducibility. The measurements were validated along the way by daily and weekly brainstorm sessions in order to optimize the observation and measurement procedures. Each anaesthesiologist and each PAC secretary were daily briefed about the manner of measuring step-by-step. We found that the data collection to be appropriate. During the whole measurement period no severe problems were anticipated. Facing an urgent need for changing the processes due to long WT and repeating poor performance assessments by patients we have already started with a multifactorial change strategy several months ago. We measured our performance before and after these initial improvement activities resulting in promising preliminary results.
C.
DMAIC: Analyse phase
C1. Baseline measurements
We performed a baseline measurement using the quantitative statistics of software
program Minitab®. 166 walk-in patients were included in a period of two weeks with
following relevant parameters:
ASA category 1 to 4
PT TOTAL: Sum of all value adding activities
WT TOTAL: Sum of all waiting time
PT ANS: Processing time of consultation by anaesthesiologist
WT ANS: Waiting for consultation by anaesthesiologist
Descriptive Statistics of Minitab® gave us a first overview of our baseline
measurements.
Figure 7. Baseline measurement of WT TOTAL: Descriptive statistics via Minitab®,
presented as histogram with a right skewed distribution.
The distribution of the data of the variable WT TOTAL is visualized as histogram in Figure 7. The data center around 20 and 40 minutes with a sample mean of 39 minutes and a sample median of 33 minutes, resulting in a right skewed distribution. Some isolated values could be identified as outliers.
Figure 8. Baseline measurement of WT TOTAL: Probability Plot via Minitab®.
The probability plot (Figure 8) verifies that our data have a normal distribution when the 3-parameter Weibull were used.
Figure 9. Baseline measurements: Empirical CDF of WT TOTAL via Minitab®.
We were interested in the frequency with which WT TOTAL is larger than or smaller than our project objective of WT TOTAL of 30 minutes for 80% of our walk-in patients. We used the empirical CDF (cumulative distribution function). Figure 9 shows that
N = 166 cases
C2. Gemba
Literally translated from Japanese as “workplace”, Gemba refers to the place where
real value is created in an organization. At Toyota, senior leaders going to the Gemba meant assisting operations: looking for problems or improvement opportunities and finding out what workers need to stay on target. It means getting to know first-hand the issues facing front-line workers, helping to work out solutions, learning and listening (69).
During our Gemba walk we as LSS team followed the steps of a patient attending the PAC one by one and thereby identified potential influence factors at each step. Viewing our processes this way - as a patient - revealed several eye-openers (Table XI).
Table XI. Results of Gemba.
Standard forms of waste
Transportation:
Transportation of medical records on paper from one outpatient
clinic to another. Literally missing medical information when record is lost.
Additional walking by doctors to PAC front desk to pick up records
Overproduction: Touching the medical record on paper multiple times to verify information.
Motion:
Patients move from one outpatient clinic and from one room to
another.
Reaching for paper forms.
Reaching for arriving documents (case notes from other specialists)
Complexity: Most complex cases, i.e. patients with co-existing diseases, attend the PAC on Wednesday and Thursday associated with significant longer WT and PT on these days.
Rework in case of not immediate PAC approval: waiting for pending medical findings.
Delays: Lack of synchronization of resources, i.e. insufficient amount resources during peak hours and peak days.
Defects = repairing mistakes in the process:
Missing anticoagulation advice by surgeon: Anaesthesiologist tries
to catch the surgeon, by phone of via mail.
Missing list of medication: PAC back office has to call pharmacy or
GP. Nurses at surgical outpatient clinics do not double check if medical record is complete, which causes more work upstream at the PAC.
Missing case notes of other specialists, e.g. cardiologist, which
creates rework. Another anaesthesiologist or resident, who has not examined the patient in the first place, has to re-evaluate the case based on incoming findings and must rely on existing pre-work of colleagues.
Managing inflow of walk-in patients
No prioritization: Walk-in patient scheduled for urgent surgery sit
next to walk-in patient scheduled for highly elective surgery.
Surgeons tell patients that they are allowed to walk-in to the PAC
without mentioning WT, which creates endless discussions at PAC check-in front desk.
Nurses at surgical outpatient clinics do not tell their patients, that there is the opportunity to make a fixed PAC appointment.
C3. CTQs and influence factors
Firstly, we had to understand why the CTQs PT and WT behave in this specific way. Identifying influence factors, which could explain the current behaviour of our CTQs, are fundamental to describe improvement measures. We can distinguish three types
of influence factors:Nuisance variables, Control variables and Disturbances.
C3.1 Nuisance variables
Nuisance variables are sources of unwanted variation and fluctuation that have to be eliminated. This includes factors that can be in principle controlled, but this could be costly or require further collaboration with our stakeholders and are associated with potential trade-offs. We observed following nuisance variables:
Variation of workload during the day: We experience in general two peak hour
periods, between 11 a.m. and 1 p.m. and between 2 and 4 p.m., which represents the moving AM and PM waves of patients from the surgical
outpatient clinics to the PAC. In figure 10 we graphed the patients’ arrival
patterns by hour of the day. The patient arrival patterns are fairly predictable, and peak at around 11 am, with a second minor peak around 2 pm. The patients get “clogged” in the system due to the peak arrivals in the middle of the day with as a consequence increasing WT.
Variation of workload during the week: Secondly, we experience two peak
days, Wednesday and Thursday, respectively (Figure 11). Most likely because of the fact, that on those days the majority of the surgeons work at the surgical outpatient clinics. This variation of workload, i.e. variation of number of walk-in patients, has significant impact on WT and PT.
Figure 10. Variation of workload variation during the day: showing the number of patients per hour during the day (Monday to Friday) with two peaks around 11 a.m. and 2 p.m.
Figure 11. Variation of workload during the week: Monday to Friday, by using
Control chart in Minitab®. Peak days are Wednesday and Thursday.
118 105 92 79 66 53 40 27 14 1 70 60 50 40 30 20 10 0 O bservation In d iv id u al V al u e _ X= 31,31 UCL= 64,62 LC L= -1,99 I C hart of Aantal_pat 15-16 uur 14-15 uur 13-14 uur 12-13 uur 11-12 uur 10-11 uur 9-10 uur 8-9 uur 7-8 uur 4 3 2 1 0 Dagdeel A a n ta l_ p a t
Time Series Plot of Aantal_pat
Num b e r o f p a tie n ts
Number of patients
118 105 92 79 66 53 40 27 14 1 70 60 50 40 30 20 10 0 In d iv id u al V al u e _ X= 31,31 UC L= 64,62 LC L= -1,99 I C hart of Aantal_pat 15-16 uur 14-15 uur 13-14 uur 12-13 uur 11-12 uur 10-11 uur 9-10 uur 8-9 uur 7-8 uur 4 3 2 1 0 A a n ta l_ p a tFigure 12. Zooming in into figure 11, Control chart: blue dots representing day during the week. On Fridays the PAC is closed for walk-in patients, which explains the weekly dip.
Variation of arrival of complex vs. non-complex patients: Patients introduce
themselves to the PAC if they finished their appointment at surgical outpatient clinic. There is no pre-selection (triage) prior to PAC arrival or even a clustered distribution of ASA categories. The only exception is currently care-cycle-patients, which can be clustered on specific days with fixed appointments.
C3.2 Control Variables
The Control Variables are parameters in the process that the LSS team or our organization could (theoretically) change. We observed following control variables:
PAC guidelines: Higher ASA categories are medically complex cases which require in general more PAC capacity, i.e. the consultation by anaesthesiologist takes more time based on medical guidelines resulting in longer PT, need for CPMs and additional findings (e.g. lab-works, case notes of other specialists). 118 105 92 79 66 53 40 27 14 1 70 60 50 40 30 20 10 0 O bservation In di vi du al :V al ue _ X= 31,31 U C L= 64,62 LC L= -1,99 I:C hart:of:Aantal_pat 15#16%uur 14#15%uur 13#14%uur 12#13%uur 11#12%uur 10#11%uur 9#10%uur 8#9%uur 7#8%uur 4 3 2 1 0 D ag deel A an ta l_ pa t
Time%Series%Plot%of%Aantal_pat
Monday
Thursday
Tuesday
Wednesday