Abstract
Background
Operational inefficiencies are ubiquitous in several healthcare processes. To improve the operational efficiency of our catheterization laboratory (Cath Lab), we implemented a lean six sigma process improvement initiative, starting in June 2010. We aimed to study the impact of lean six sigma implementation on improving the efficiency and the patient throughput in our Cath Lab.
Methods
All elective and urgent cardiac catheterization procedures including diagnostic coronary angiography, percutaneous coronary interventions, structural interventions and peripheral interventions performed between June 2009 and December 2012 were included in the study. Performance metrics utilized for analysis included turn-time, physician downtime, on-time patient arrival, on-time physician arrival, on-time start and manual sheath-pulls inside the Cath Lab.
Results
After implementation of lean six sigma in the Cath Lab, we observed a significant improvement in turn-time, physician downtime, on-time patient arrival, on-time physician arrival, on-time start as well as sheath-pulls inside the Cath Lab. The percentage of cases with optimal turn-time increased from 43.6% in 2009 to 56.6% in 2012 (p-trend < 0.001). Similarly, the percentage of cases with an aggregate on-time start increased from 41.7% in 2009 to 62.8% in 2012 (p-trend < 0.001). In addition, the percentage of manual sheath-pulls performed in the Cath Lab decreased from 60.7% in 2009 to 22.7% in 2012 (p-trend < 0.001).
Conclusions
The current longitudinal study illustrates the impact of successful implementation of a well-known process improvement initiative, lean six sigma, on improving and sustaining efficiency of our Cath Lab operation. After the successful implementation of this continuous quality improvement initiative, there was a significant improvement in the selected performance metrics namely turn-time, physician downtime, on-time patient arrival, on-time physician arrival, on-time start as well as sheath-pulls inside the Cath Lab.
Highlights
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Lean six sigma has been used to improve operational efficiency in several non-medical manufacturing firms.
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We studied implementation of Lean Six Sigma Process Improvement initiative in our Cath Lab.
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This led to improvement in the Cath Lab turn time during 2009–2012.
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This led to progressive improvement in on-time start during 2009–2012.
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There was improvement in operational efficiency of our Cath Lab after implementation of lean six sigma process.
1
Introduction
Operational inefficiency is ubiquitous to most current healthcare delivery systems. Some of these operational inefficiencies arise due to impediments and redundancies in the direct medical service delivery process. Others seem to be associated with the logistical, administrative and operational aspects of the healthcare delivery system. Both of these areas are amenable to systematic process innovation and improvement activities. It is well known that improvement in healthcare service quality results in an improvement in patient satisfaction . This improvement in patient satisfaction is beneficial to the healthcare organization by achieving high levels of patient retention and loyalty. In addition, improvement of operational efficiency should help reduce healthcare costs by eliminating redundancies and streamlining workflow.
The cardiovascular catheterization laboratory (Cath Lab) is an integral part of the cardiovascular care provided at any healthcare institution. With rising healthcare costs and reducing human resources, it is imperative that all cardiovascular programs scrutinize the current workflow process in an attempt to minimize the inefficiencies and maximize Cath Lab utilization. This is of critical importance to ensure that we are able to offset declining reimbursement and do not succumb to economic losses. Several management tools have been utilized in non-healthcare manufacturing industries to eliminate operational inefficiencies and improve productivity. Lean thinking and six-sigma are two process innovation approaches that are extremely popular in manufacturing industries. The lean six sigma approach underscores continuous process improvement along with elimination of redundant non-value added activities. Healthcare organizations have begun to embrace lean six sigma concepts after these have been fully developed and tested in the manufacturing sector by major corporations like Motorola, Toyota and General Electric . It has been suggested that lean six sigma implementation may benefit healthcare organization in terms of improved operational efficiency, greater degree of cost-effectiveness and a higher process quality . There have been a few studies that demonstrated the beneficial effects of lean six sigma process improvement initiatives in the setting of emergency departments and operating rooms . However, these management tools have never been utilized to improve Cath Lab workflow. We aimed to study the impact of lean six sigma implementation on improving the efficiency and the patient throughput, in the context of a busy, tertiary-care Cath Lab setting.
2
Methods
2.1
Study population
All elective and urgent cardiac catheterization procedures including diagnostic coronary angiography, percutaneous coronary interventions, structural interventions and peripheral interventions performed between June 2009 and December 2012 were included in the study. Emergent procedures and Cath Lab activations for acute ST elevation myocardial infarction were not included in the study. The study was approved by the Cleveland Clinic Institutional Review Board.
2.2
Process improvement initiative
To understand the intricacies of the workflow process in the Cath Lab, a value-stream map was first constructed ( Fig. 1 ). A value stream map is a primary analytic tool of the lean process management. It refers to a process flowchart depicting the continuity of flow, which helps identify potential bottlenecks and may be used to guide quality improvement activities. It is a compilation of all actions, both value-added and non-value added, required to complete a process. It helps the improvement team understand the nitty-gritties of the process including material and information flows, time elapsed at each step and potential redundancies. The value stream is a lean concept used to establish a consistent view of the workflow in the same manner the patient experiences it.
After establishment of a value stream map, a systematic collection of time-stamps for various components of the entire Cath Lab process for each procedure was initiated using a structured database in June 2009. An internal assessment of the existing workflow process was conducted during March through June 2010 using the data that had been collected until that time. Based on this assessment, it was decided to implement a continuous quality improvement initiative with the help of a process improvement specialist team. This team was comprised of healthcare management experts, department administrators, the Cath Lab manager, nursing supervisors, the medical director of the Cath Lab as well as interested physician representatives. After extensive review of the existing workflow process and its perceived inefficiencies, the team decided to roll out a comprehensive scheme to make the workflow more organized and efficient. The process improvement initiative was based on the lean six sigma principles, which have been utilized in several other manufacturing industries . After an initial implementation, the entire team met at regular intervals to study the changes in the workflow and make further amendments to the workflow process, as needed. The timeline of the continuous quality improvement initiative is shown in Table 1 where several performance metrics were identified to monitor quality improvement in March 2011. These included turn-time, physician downtime, on-time patient arrival, on-time physician arrival and on-time start. The time-stamps were derived from the Cath Lab reporting system. As a part of the quality improvement initiative, we developed a system, wherein the Cath Lab personnel are routinely required to time-stamp important time-points, which were the focus of process improvement. These include the time of patient arrival, the time of physician arrival and the time of case termination. The start times for the Cath Lab have been maintained for several years by the Cath Lab management staff. After the identification of the quality metrics, it was recognized that removal of the sheath inside the Cath Lab and subsequent manual compression significantly elevated the turn-time between cases. To optimize this turn-time, we established a sheath-pull process, wherein manual sheath-pulls would be accomplished by trained personnel in the patient prep area outside the Cath Lab. In view of this, the proportion of manual sheath pulls performed in the Cath Lab was also identified as a quality metric. The definitions of these performance metrics and the established goals are shown in Table 2 .
| Time | Process Changes Effected |
|---|---|
| June 2009 |
|
| March–June 2010 |
|
| March 2011 |
|
| April 2011 |
|
| May 2011 |
|
| June 2012 |
|
| Quality metric | Definition | Established goal |
|---|---|---|
| Turn time | Duration between the exit of the preceding patient and the arrival of the next scheduled patient in the Cath Lab | ≤ 20 min |
| Physician downtime | Duration between achievement of hemostasis and the arrival of the next patient. | ≤ 35 min |
| On-time patient arrival | This was said to occur if the duration between the designated Cath Lab start time and patient arrival was ≤ 15 min. This metric was monitored for the first case of the day only. | ≥ 75% |
| On-time physician arrival | This was said to occur if the physician was present in the Cath Lab within 15 min of the designated Cath Lab start time or within 15 min of the patient arrival to the Cath Lab. This metric was monitored for the first case of the day only. | ≥ 75% |
| On-time start | This was defined as an on-time patient arrival and an on-time physician arrival to the Cath Lab. This metric was monitored for the first case of the day only. | ≥ 60% |
| Sheath pull inside Cath Lab | Proportion of all manual sheath-pulls performed inside the Cath Lab. This metric excluded those patients that underwent cardiac catheterization via radial route or those patients who had a successful vascular closure device implanted. | ≤ 33% |
2.3
Statistical analysis
Statistical analysis was performed using STATA v. 13.1 (Stata Corporation, College Station, TX, USA). All study-outcomes were analyzed as binary variables, based on whether or not they met the established goal. We calculated the proportion of total cases that met individual established goals for each calendar year. Subsequently, a test for linear trend across the years was performed using a linear contrast of coefficients derived using logistic regression analysis incorporating the calendar year as an indicator variable with multiple predictor levels . A p-value < 0.05 was considered statistically significant.
2
Methods
2.1
Study population
All elective and urgent cardiac catheterization procedures including diagnostic coronary angiography, percutaneous coronary interventions, structural interventions and peripheral interventions performed between June 2009 and December 2012 were included in the study. Emergent procedures and Cath Lab activations for acute ST elevation myocardial infarction were not included in the study. The study was approved by the Cleveland Clinic Institutional Review Board.
2.2
Process improvement initiative
To understand the intricacies of the workflow process in the Cath Lab, a value-stream map was first constructed ( Fig. 1 ). A value stream map is a primary analytic tool of the lean process management. It refers to a process flowchart depicting the continuity of flow, which helps identify potential bottlenecks and may be used to guide quality improvement activities. It is a compilation of all actions, both value-added and non-value added, required to complete a process. It helps the improvement team understand the nitty-gritties of the process including material and information flows, time elapsed at each step and potential redundancies. The value stream is a lean concept used to establish a consistent view of the workflow in the same manner the patient experiences it.
