O speculators about perpetual motion, how many vain chimeras have you created in the like quest? - Leonardo Da Vinci
No search so compelled the 15th-century engineer as that of the perpetual motion machine (Figure 1A). It seemed elusively possible to create a wheel, containing strategically placed levers or flowing liquid mercury, with perpetual imbalance sustaining endless motion. Motion produces energy, energy drives motion, in a virtuous cycle of self-perpetuation.
We have entered our own health care renaissance of quality, safety, and efficiency. Untold numbers of highly motivated teams are initiating improvement projects within clinical microsystems. Some of these projects succeed, and when this occurs, it is alluring to believe that success will inevitably lead to more success. The team will gain skills and, through experience with the initial successful quality improvement (QI) initiative, develop greater sense of efficacy and agency. Improvements will spread driven forward by their own momentum. As the circle of impact and ability grows, teams and organizations should go on more extensive and efficacious QI, with accomplishments realized with continuously accelerating pace. This interplay would become the virtuous cycle of QI (Figure 1B).
Unfortunately, this description often does not comport with lived experience. Even when improvement projects succeed, phrases such as "lack of bandwidth" or "change fatigue" contradict the emergence of a perpetual positive feedback loop. Change fatigue represents a manifestation of stress in response to ongoing change in the workplace.1 Distinct from resistance to change, with change fatigue individuals may approve, and even be driving, the change yet may develop burnout that limits ongoing engagement and efficacy. A key evolution in the modern clinical quality movement requires a conceptual model that helps us understand the failure of reality to match the theoretical possibility of QI reinforcing its own, perpetually positive, feedback loop.
Da Vinci created schematics for both perpetual motion and flying machines. His design of the ornithopter offers insights into impeding feedback forces. The physics of flight are complex and fascinating-the airfoil shape drives air faster over the top of the wing than the bottom. Faster moving air on the superior surface has lower pressure, creating lift on the underside of a wing, a principle used in aircraft design to this day. However, this phenomenon also spawns an important secondary effect. Wingtip vortices spiraling behind the body in flight create twin downdrafts that reduce lift-"induced drag." The by-product of forward movement is a secondary loop of pressure in the opposite vector of lift.
This interplay between 2 opposed forces, one created by the other, offers an important framework for QI in health care. Forward momentum of QI initiatives generates secondary negative feedback loops acting to slow continued progression. As an example, consider a QI project designed to reduce unsafe drug-drug interactions in hospitalized patients. The project team gathers baseline data, engages stakeholders, brings together experts, and develops a consensus guideline on use and monitoring of medications that can prolong the QTc and induce cardiac arrhythmia. An extensive educational campaign about the new institutional guideline follows, and the QI team distributes laminated cards to physicians across the hospital. Early results show extraordinary increase in awareness, better monitoring, and marked reduction in unsafe prescribing. Encouraged and empowered, the QI team takes on 2 new projects targeting readmissions and patient satisfaction. Splitting their energy between these 2 new projects, they find progress slows. Worse yet, midway through these efforts, the team discovers a regression to the mean in their prior project focused on drug interactions. Subsequent project focus is diluted by ongoing energy devoted toward maintaining the safe prescribing initiative.
The more successful projects completed by the team, the greater the energy necessary to maintain the factors driving original success. Less bandwidth remains to initiate new projects. Overconfidence created by success induced the team to assume multiple new projects, with fewer resources to devote to each one. Progress slows, confidence wanes, and enthusiasm fades in an accumulation of drag. Eventually, progress grinds to a halt or an early initiative is allowed to fail. A pattern likely to induce "change fatigue."
The interplay of factors at the confluence of these reinforcing and balancing feedback loops is termed "systems thinking."2 Understanding the model of the system allows insight into points of leverage. Peter Senge2 describes the general patterns of systems as archetypes. The QI team in our example is trapped within a system archetype described as "Limit-to-Growth" (Figure 1C). Off the starboard wingtip, drag is introduced by the negative feedback vortex of active project monitoring and maintenance, and from the port wingtip, we observe the downdraft effect of divided attention from running more simultaneous projects than the resources of the clinical microsystem can support. In the Limit-to-Growth system archetype, it is futile to simply push harder in the primary loop. Exhorting the team to take on more projects only causes the balancing feedback loops to gain strength.
The Limit-to-Growth archetype conceptual model raises important questions: How can changes be embedded into hospital systems to reduce friction from maintenance balancing loops? How can QI teams assess the match between resources and demands to achieve optimal pace of change? How should leaders monitor progress speed to identify when drag is beginning to develop? How can the skills developed by the initial team members be leveraged, or additional participants be recruited, to expand bandwidth for subsequent projects?
The search for a perpetual motion machine has proven futile, but this is not to suggest that careful engineering cannot dramatically reduce friction within a mechanical system. Change fatigue is no mystery. It is the predictable consequence of the negative feedback loops generated by QI success. The Limit-to-Growth system archetype offers insights into the ability to sustain QI project team efforts over time. Recognizing the action of the Limit-to-Growth system archetype allows leverage to be applied to maintain QI momentum.
REFERENCES