Ambiguity Tolerance and Quality

What single characteristic among practicing physicians do you think has been associated with all of the following clinical outcomes?

• increased test-ordering, 
• failure to comply with evidence-based guidelines, 
• increases in patient charges, 
• withholding negative genetic test results, 
• fear of malpractice litigation
• defensive practice, 
• increase rates of burn out, and
• discomfort in the context of death and grief

(Source: Geller G., Acad Med. 2013;88:581–584)

The answer is low "ambiguity tolerance."  I think we can add to this list two other characteristics, one of which is failure to make diagnoses (and I am referring here not to making the wrong diagnosis, but to the more subtle problem of avoiding the diagnostic process altogether).  The other involves clinical behaviors that result in harmful errors of overuse.  

Osler himself recognized that clinical life meant dealing effectively with problems of diagnosis and treatment in an environment of chronic uncertainty.  "In seeking absolute Truth" he wrote, "we aim at the unattainable."  Several factors have come together to exacerbate this problem for 21st century physicians.

One is certainly the division of labor which occurs in the hospital setting.  The contemporary Emergency physician has been trained to understand that his role is (1) to rule out a short list of life threatening conditions, and (2) to determine which patients are sick enough to require admission.  Note that neither of these activities necessarily requires that the physician make a diagnosis.  In this way the uncertainty problem is neatly sidestepped.  

Of course, this only moves the problem downstream.  (For the treat-and-release patient whose presenting problem was "headache" and whose discharge diagnosis is also "headache" the downstream physician is in the community.  Happily, such physicians still make diagnoses).  For the admitted patient, it is typically a hospitalist who is faced with the dilemma of making diagnoses.  Where the patient's complaint (say, dyspnea) could be the result of more than one disease process (say COPD, pneumonia or heart failure) there are two common strategies for avoiding diagnostic uncertainty - treat for all three, or call consultants (or both).  Unfortunately, this approach leads to overtreatment, and occasionally to contradictory imperatives.  (Do we increase the fluids, consistent with sepsis management, or restrict them as part of heart failure care?)  

A second factor is the electronic health record itself.  For a host of reasons, what was once a standard summation of the case, pulling together the key points from the history, exam and testing, ending in the same sentence with a working diagnosis ("...most consistent with community acquired pneumonia complicating the patient's chronic systolic heart failure...") is now a series of hashtag items syntactically disconnected (...#dyspnea #hypoxemia #HF #CAP...) thus leaving the reader free to interpret the writer's mental model of the case in any variety of ways.  This also relieves diagnostic uncertainty.  The less one commits to statements of diagnosis or symptom causation, the less likely it is that one can be wrong.

A third factor comes from the quality movement itself.  The PDSA model for improving "processes" took as its premise that 100% of patients with diagnosis X should receive treatment Y, where Y is an intervention supported by evidence, expert consensus or both.  So far, so good.  The problem is that as a healthcare community we came to believe that the underlying implication of this model is valid - which is that the first step of the process, i.e. making the diagnosis, is fairly trivial.  As we know, it is NOT!  All the focus has been on getting from X to Y, when getting to X is arguably the deeper problem.  

Additionally, this model of improvement tends to focus single mindedly on errors of underuse - failing to give the thrombolytic or the beta blocker or the antibiotic.  However, where diagnostic uncertainty is managed poorly, the usual error is the reverse - exposing patients to known risks of a host of interventions where the likelihood of benefit is very small. 

And so my Christmas wish list includes the following for all of us who care for patients...that we rediscover the value of the expert generalist...because there's no "dyspnea specialist," other than the internist, family physician or pediatrician...that we take seriously the issue of overtreatment (primum non nocere), and...that we rediscover the age old but still needed process of taking an incisive history, performing an accurate physical examination, and ordering tests only to confirm or rule out hypotheses, which is to say that we rediscover how to brave the blizzard of ambiguity, following the North Star of clinical reasoning to reach the all-important destination that is the diagnosis.