Who's Counting? Bad Systems, Not Bad Medicine

— -- — Recently, the National Academy of Sciences distributed awell-publicized report stating that each year, between 40,000 and 100,000deaths in this country are a consequence of medical error.

After reading "ToErr Is Human," the report put out by the NAS’s Institute of Medicine, Iwas left with one dominant impression: the problem of medical error is notso much a medical problem as a systems problem, almost a quasi-mathematicalone.

I’m a mathematician, so you may suspect this conclusion is a result ofmy professional myopia, of my confusing an ankle for an angle perhaps. Let me explain.

People readily understand instances of a physician’sincompetence, a nurse’s negligence, a pharmacist’s lapse. These are allagents who are culpable, and making mistakes is in everyone’s realm ofexperience.

What’s much more difficult to grasp is a complex system withmany interacting parts that are tightly coupled and interdependent. Suchsystems are necessary in modern health care, but unless an impersonalanalysis of their structure is made, we likely won’t put a significant dentin the intolerably large number of medical errors or in the sickeninglyunnecessary deaths they lead to.

Look to the Skies

It is possible. Consider the airline industry whose safetyrecord is extraordinary and getting better. As has often been noted, aperson has one chance in 7 million of dying in any given flight with acommercial airliner in this country, and such deaths, befalling across-section of healthy Americans, are never overlooked by the media.

Accidents are rare and spectacular and, as the saying goes, pilots are thefirst to arrive at the scene.

In the health care industry, fatal accidents are common — occurring in from 1 in 200 to 1 to 400 visits toa hospital — are woefully underreported and happen to sick, isolatedindividuals and not to any of the medical staff.

The airline industry, of course, differs in countless ways fromthe health care industry. Medical outcomes often come in shades of gray, andthe questions of what constitutes an error and whether a death can beattributed to any given error are sometimes difficult to answer.

Nevertheless, the systems that are in place in the airline industry providean unfriendly environment for errors to occur or to propagate.

Different Approaches

Some examples: Engineers don’t scribble their analysis of aproblem part on a piece of paper and leave it for someone on the next shiftto decipher. Factory personnel don’t test parts in isolation but runsimulations to see how they work together. Managers don’t introduce newequipment without an extensive program to train people in its use.

Pilotsand others report accidents and near-collisions to various authoritiesfor tabulation and investigation. Designers build in fail-safe and ergonomicimprovements to minimize confusion and the need to rely on memory. No onetakes pride in doing his or her job on three hours sleep or in being aloof fromhis or her support team.

In general, accidents occur more frequently in complex systems.

As an unrealistically simple illustration, take a procedure that depends on30 independent component parts (tubes, machines, scalpels, medications,rates and doses, clamps, etc.) working correctly. The laws of probabilitytell us that even if each component works flawlessly 999 times out of a1,000, the procedure will still fail 3 percent of the time (since 0.99930 = .97).

Designing Safety

The dependencies in the procedure have to be anticipated and analyzed, theprobabilities of component failure have to be reduced, and redundancies andbackups must be built in. Computers and software should be used inprescribing drugs, in recording patient histories and wherever else isappropriate.

These and the other efforts recommended in “ToErr Is Human” have little to do with medicine and much to do with operationsresearch and systems theory.

Let’s help insure that these recommendationsare implemented by making the following New Year’s resolution: Let news coverage of every plane crash remind us of the tens of thousands of almostinvisible deaths due each year to medical error.

The story of these deathsand of the systematic errors that lead to them is harder to cover but moreimportant than that of the random plane crashes that so intrigue us.

Professor of mathematics at Temple University, John AllenPaulos is the author of several books, including AMathematician Reads the Newspaper and OnceUpon a Number. His Who’s Counting? column on ABCNEWS.com appears on the first day of every month.