Wednesday, May 16, 2018

"Perseverance is not a long race; it is many short races one after the other."

I was searching on the Internet for a catchy quote that would go with today's blog post, and I happened to find this one by someone named Walter Elliot (who could be a number of individuals, including a Scottish politician, a Roman Catholic priest, the former Canadian Surgeon General, or a Scottish naturalist - the website did not specify).  Anyway, I think it fits for what I wanted to talk about today.

If you are familiar with ancient Greek philosophy, you have probably heard of an individual named Zeno of Elea and his set of nine paradoxes (there were likely several more, but only nine have survived through antiquity).  All nine surviving paradoxes came down to us through the writings of the ancient Greek philosopher, Aristotle.  Zeno described several paradoxes to support a doctrine reportedly first proposed by Parmenides (another ancient Greek philosopher who founded the Eleatic school of philosophy and who was the subject of Plato's dialogue, Parmenides) that essentially stated that motion is nothing but an illusion, so change is also an illusion.  Okay, I get it - this is probably more ancient Greek philosophy than you wanted to hear, but bear with me! 

Zeno's most famous paradoxes is frequently called "Achilles and the tortoise" (the so-called "dichotomy paradox" is very similar - so much, in fact, that Aristotle believed that they were one in the same).  Aristotle described the paradox simply as, "In a race, the quickest runner can never overtake the slowest, since the pursuer must first reach the point whence the pursued started, so that the slower must always hold a lead."  As the story goes, Zeno imagined that the Greek hero, Achilles was challenged to a footrace by a tortoise.  Achilles was a gracious and fair fellow, so he gave the tortoise a head start of 100 paces.  If both Achilles and the tortoise start at exactly the same time ("On your mark, get set, go!"), and if both Achilles and the tortoise run at constant speeds (Achilles being very fast and the tortoise being very slow), then after a finite period of time, Achilles will reach the point where the tortoise started (100 paces away).  Importantly, the tortoise will no longer be there!  He has moved, albeit slowly, to a new place, just a little farther away.  Now, it will take Achilles a finite period of time to cover the new distance that separates him from the tortoise, and he will eventually reach where the tortoise was after the race started.  Again, the tortoise will not be there, as he has moved to a new position, just a little farther away.  In this manner, whenever Achilles arrives at the point where the tortoise has been, he will still have some distance to go before he can reach the tortoise.

Kind of strange logic, right?  Well, here is how Aristotle described the "dichotomy paradox" (again, Aristotle claims that the "dichotomy paradox" and the "Achilles and the tortoise paradox" are basically saying the same thing).  Aristotle describes this paradox as, "That which is in locomotion must arrive at the half-way stage before it arrives at the goal."  In other words, if you are walking from point A to point B, you will cover a certain distance, say half the distance, in a certain amount of time.  If you cut the distance from your new location to point B in half yet again, you will be at a new point, which is still not at point B.  If you keep cutting the distance by a half, you will never, in fact, reach point B!

So what's my point?  We are always talking about goals in the health care industry.  There are a number of organizations that have proudly announced the laudable goal of eliminating all patient harm (for example, eliminating all central line infections or eliminating all pressure ulcers).  I once wrote an editorial about getting to zero harm ("Getting to 'zero' harm on central-line infections in the PICU") and basically described some of the elements of Zeno's paradox.  In the world of continuous improvement, can we ever really get to zero harm events?  Thinking about the two paradoxes described above (especially the "dichotomy paradox"), if our goal every year is to reduce, say the number of central line infections by 50%, we will never, in fact, get to zero (for example, if we have 100 central line infections per year and decrease that by 50%, we will now have 50 infections; if we reduce that by 50% the following year, we will have 25 infections, etc, etc).  Don't get me wrong - the goal to eliminate patient harm is clearly justified and appropriate.  However, in the editorial I questioned what we mean when we say that our goal is zero harm.  What exactly does zero mean?  Can we say that we have reached the goal of zero harm when we have no events for 1 month?  How about for 6 months?  1 year?  The problem is that we really can't define "zero harm" clearly, and we end up with something akin to Zeno's paradox.

W. Edwards Deming, one of the founding fathers of quality improvement, claimed that "zero defects" should never be the goal, stating "A goal that lies beyond the means of accomplishment will lead to discouragement, frustration, and demoralization."  Motorola's "six sigma" standard is not zero defects, but rather 3.4 defects per million chances (which admittedly is pretty close to zero).  Both Deming and Motorola were talking about manufacturing defects and not patient harm, but I do think there is something here for us to learn nonetheless. 

Zero harm is the right goal.  However, I think we need to be clear about what we mean when we say "zero," otherwise I think we end up with a version of Zeno's "dichotomy paradox."  Mr. Elliot's quote perfectly describes my take-home message.  The goal to eliminate patient harm in health care is "not a long race."  Perhaps the goal to eliminate patient harm is a series of "many short races one after the other" instead.

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