Published in the March 2015 issue of Today’s Hospitalist
EVEN PHYSICIANS who’ve never considered getting an MBA know the theory behind Lean Six Sigma. That methodology, which is part of a system of operational management first championed by Toyota, scrutinizes all the steps in a process to remove the ones that don’t add value.
Yet there’s another theory that can be used in combination with Lean, but is less well-known: the theory of constraints. It too rose out of industrial manufacturing and is a business-school staple.
But unlike Lean, where adherents seek to eliminate wasted steps, “the theory of constraints has us look at each step independently, then focus all our efforts on the slowest one, the one that in chemistry is known as the rate-limiting step,’ ” says Dean Dalili, MD, MHCM, senior vice president of medical affairs in the hospitalist division of Hospital Physician Partners. “According to the theory, the one step in the process that has the least amount of capacity is always the one you’re trying to fix “and the only one.”
Why? “Because any effort to optimize or fix a step that’s not your slowest one will never improve the overall speed of the system,” Dr. Dalili explains.
That may make sense on an assembly line where one machine can process only half the number of widgets as the other machines it is linked to. But how does that apply to hospital medicine?
“The theory of constraints has us look at the capacity of the machine that determines the workflow “and in the hospital, that machine is the hospitalist,” says Dr. Dalili who, along with TeamHealth’s Jasen Gundersen, MD, MBA, is presenting on real-world applications of the theory of constraints at this month’s Society of Hospital Medicine annual meeting. “The theory can help us change how we think about maximizing doctors’ capacity to do their job most efficiently.”
Lining up in bed
In manufacturing, Dr. Dalili points out, it’s easy to identify constraints: Find those steps in the process where everything slows down, and lines begin to form.
But health care is more of a challenge, he says, because all those lines are hidden. Patients don’t wait in lines, but in beds. While those “lines” aren’t always visible, they certainly crop up in longer lengths of stay.
“Patients are queuing up in bed,” he says. “Any time a nurse complains that someone is waiting for a test, a consultant or discharge, that tells you where your longest lines are and helps you focus on the most critical constraint “your doctors “in the process.”
Sometimes groups are just short-staffed, making it impossible to do what those with MBAs refer to as “exploiting the constraint”: managing it so the constraint at least functions as efficiently as possible. When you have too few doctors to allow each to function at maximum efficiency, hiring more providers may be the first fix proposed.
But many times, managers can apply the theory of constraints to shift resources already in place so physician capacity better matches demand. That way, at least, the constraint is being efficiently managed.
Consider programs where day-time physicians leave at 7 p.m., leaving one desperate nocturnist to deal with a growing line of admissions backed up in the ED. To manage that constraint, groups can reassign day-shift physicians to an evening swing shift or bring in moonlighters for evening admissions.
At Wuesthoff Medical Center in Rockledge, Fla., where Dr. Dalili practices, applying the theory has steered the hospitalist group to turn over much of its observation care to its six nurse practitioners/physician assistants, rather than to its 10 physicians.
“Another way to achieve maximum efficiency from limited resources in medicine is to look at patient acuity and provider allocation,” Dr. Dalili points out. “Assigning physicians to observation units can mismatch high-capacity providers to low-acuity patient needs. You can usually make your capacity between 10% and 20% more efficient just by thinking about how to better organize workflow without adding resources.”
Patient encounters, scheduling
Or take this perennial question: What’s the right number of patients or encounters per day? Fifteen is often cited as optimal in terms of safety and quality. According to Dr. Dalili, between 15 and 18 is much better than, say, between 20 and 25 in terms of managing your biggest constraint: your physicians.
“In the hospital, hospitalists are the rate-limiting step because everyone else is waiting for them: the labs, pharmacy, nurses, therapists “doctors set them all in motion,” he points out. When doctors’ census is too high, the “constraint” with the least capacity “the doctor “works much less efficiently.
That leaves all the other “steps,” such as the labs, orders and consults, waiting until the end of the day to kick in.
Then there’s this key question: What’s the right schedule? Many critics fault seven-on/seven-off as being tough to sustain. But the schedule promotes continuity, Dr. Dalili points out. And maximum continuity minimizes the duplication of work associated with handoffs.
“If I take care of 15 patients today, my processing time on those patients tomorrow is going to be much faster because they’re familiar to me,” Dr. Dalili says. But if you hand those patients off, “a different physician has to learn those patients from scratch, so he or she is going to go much, much slower. With a schedule where people are switching in and out, you’re making the workload harder and losing capacity, even if patient volume doesn’t rise.”
Maximizing physician capacity likewise informs his group’s policy on working extra shifts. “We don’t have people come in and do one or two shifts,” he says. “We want people to pick up a minimum of three or four. We don’t want to build unnecessary handoffs into the system.”
Lower length of stay
In another bid to manage physician constraints around handoffs, Dr. Dalili says his group opted to augment face-to-face signouts with electronic ones through Ingenious Med. Routine issues are conveyed electronically, so doctors can spend their handoff time discussing patients who are acutely ill.
“That way, signout isn’t as much of an extra step,” he says. “Less duplication of effort uses physician time more efficiently.”
Applying the theory of constraints when his company first took over the hospitalist program at Wuesthoff Medical Center, the group made three innovations to maximize physician capacity: some hiring to drive the individual census down, scheduling for continuity and incorporating electronic handoffs.
“Over the course of six months,” he says, “we saw the program’s length of stay drop by 25%.”
Using the theory has since led the group to implement unit-based rounds so physicians aren’t running from unit to unit, making patients line up in their beds until the end of the day waiting for a doctor.
But as new patients are admitted or transferred to other units, “doctors follow them,” says Dr. Dalili. “We prioritize continuity over geography for patients we already know.” In an environment with limited resources, “we can’t afford to waste time or resources by focusing on the wrong steps in the process. The theory of constraints helps you identify those changes that drive the biggest improvement.”
Phyllis Maguire is Executive Editor of Today’s Hospitalist.