The Hot Dog Rule

     Early on in life I learned something called the "Hot Dog Rule." The rule can be applied to food, people, or just about anything. This rule is known to almost everyone, in various forms. But the Hot Dog version is the most explicit. The rule is simple: If you love something, never find out how it's made. An investigation into any topic, no matter how initially pure or innocuous will end up unearthing some information that will potentially ruin that topic. The most poetic form of this rule I've ever read is in Mark Twain's "Two Ways of Seeing a River." It's short, and I suggest you read it if you are not familiar. 
 
     I began to vaguely get a notion of this while still in medical school. Part of our curriculum involved reading a book on reflections by physicians alongside our didactic lectures, and early on there was a case regarding a young woman. She went dancing at a friend's wedding, and scraped her toe on the inside of her shoe. Something we've all done, and never thought about afterwards. This woman had the misfortune of contracting a devastating infection called necrotizing fasciitis. This aggressive infection tore through her muscles and bones over the course of hours, and required radical surgical debridement and quite a bit of luck to save her. Her injury had been minor, but now I knew what was possible from a single scratch.

     Later that week I was playing soccer and I noticed an abrasion on my leg, and immediately it struck me. Necrotizing fasciitis. Unlikely, but it could be. The way I viewed the world had changed. I was not seriously concerned about this infection, but the association was formed and over the next several years, many others would be formed. Of course, physicians are trained to work around this mild hypochondriasis, but like Mark Twain, with repetition these links solidified in my mind.
 
     The first thing I crossed off my "list" was a trampoline park. My brother broke his ankle quite badly in one, and while he ended up okay, I thought that the surgery, physical therapy, and eventual recovery were terribly inconvenient. I started practicing medicine and I saw dozens more ankle injuries exactly the same way. I saw worse than ankle injuries. The first time I participated in an organ harvest, the patient was a victim of the trampoline park and was left comatose. In my mind, this activity was off limits, because it was a disaster waiting to happen, and almost nothing else.
 
     It was fine though, I'm not a gymnast, and I've never really missed out by not doing a backflip or acrobatic somersault. But slowly, the list grew: ATVs became death traps on wheels. Chiropractors became distributors of spinal cord injuries. Potato salad at a barbecue was an automatic date with diarrhea. I had a mental list of things that I wasn't willing to do, because I knew of the potential consequences.
 
     And these decisions were okay. This admittedly ridiculous list of things I would never consider, simply because I'm exposed to the minority of people who have horrific outcomes never really encroached on my personal way of life, so I let it build. But practice medicine long enough, and you'll see basically every possible endeavor gone wrong. This last one was the straw that broke the camel's back for me. 

     First though, I'll admit that my least favorite chief complaint in the emergency department is dizziness, or vertigo. Vaguely described, it afflicts patients of any age. It is extremely alarming to patients, and is often debilitating. The reason I hate this complaint is because it is caused by two possible processes. One is benign, a non-emergency best worked up over weeks by a general practitioner with referral to the appropriate specialist. The other is a time sensitive catastrophe with potentially permanent neurologic deficits. There are no clear ways to determine, outside of an extensive evaluation, which of these two etiologies are responsible. Additionally, the results of any physical examination are unreliable (partially because of the potential for such a poor outcome). Whenever I decide to not perform the full workup, it's an extremely deliberate decision, and a calculated risk.

     In this particular case, this was an extremely healthy young woman who presented with headache and dizziness. Despite her general state of health, something about her combination of history and symptoms was setting off alarm bells, and we opted to go through with the entire workup. During the history-taking portion of the interview, the patient had mentioned that she had been using a portable neck massager prior to the onset of her symptoms. We ordered a CT scan of her brain and neck, looking for any possible pathology that could shed light on her symptoms. Far down on the list of possible causes is a traumatic injury to the vessels of the brain called a vertebral artery dissection. This injury is usually seen in the setting of significant trauma, which this patient didn't have. Before the results of the study came back, my thoughts were already swirling: could this be due to the neck massager? Am I about to lose a neck massage to the Hot Dog Rule? The mechanism was plausible, but only in a theoretical way. I had never even heard of a case of significant vascular injury from a vibrating motor. Of course that's exactly what happened. This was a one in a million chance, but it was staring me right in the face.

     Ultimately, I realized that if I let the list continue, I would find a reason to stop doing everything I currently enjoy. I never applied the concept to the way I practiced medicine, and applying it to my life therefore seemed silly. The Hot Dog Rule wasn't made to promote ignorance, it was made so that we could continue to eat hot dogs. I know many physicians whose practice has changed their behavior and views on life, and I'm sure I'll continue to be shaped by my patients, but I'll take these cases as spectacular phenomenon rather than a warning of impending disaster. Except for ATVs, I'm never getting on an ATV.