Wednesday, May 23, 2007

When are symptoms of GERD not really GERD symptoms?

Getting information that tends to support one's own biases is generally warmly satisfying --- sort of like getting how a child feels receiving unexpected presents in the few days after Christmas. Such is the case for me with a study published in this month's Journal of Gastrointestinal Surgery. The study, entitled Recurrent Heartburn after Laparoscopic Fundoplication is Not Always Recurrent Reflux, comes from Aussie surgeons at the University of Adelaide, and it is another salvo in the continuing debate between us peaceable and fun-loving surgeons and those nasty and dastardly gastroenterologists. Think Dudley Do-Right and Snidely Whiplash, if it suits you.

Skip this part if you don't want a 10¢ primer on reflux disease.

Perhaps a little background is in order. A whole lotta people suffer from heartburn --- gastroesophageal reflux disease, or GERD, to be technically correct. Some of them, however, don't just get the occasional dyspepsia from being forced to watch 24-hour news coverage of Paris Hilton, but really suffer from reflux of stomach contents (and acid) for a considerable part of each day. Some Smart GuysTM invented great medications to help with this, relegating antacids to the back burner --- first H2 blockers and then proton pump inhibitors (PPIs). These meds provide great relief to a huge number of patients. However, they really provide a chemical solution --- stopping acid production in the stomach --- to a mechanical problem: the process of acid and other stomach contents washing back up into the esophagus, due to an ineffective lower esophageal sphincter. You see, the issue is not that these patients make "too much" acid, it is that the acid (and bile, and food, and -- well, you get the picture) goes the wrong direction, and the esophagus really doesn't like that very much, so the patient feels like they just swallowed a cup of battery acid and chased it with $3/quart tequila.

Those of you who are quick on the uptake are now asking "well, why doesn't some other Smart GuyTM come up with a mechanical solution to GERD?" Actually, we have an operation that does just that --- it's called a fundoplication (or Nissen fundoplication, named after a pretty Smart SurgeonTM named Rudolf Nissen who devised it several decades ago). Briefly, it involves wrapping the upper part of the stomach (the fundus) around the bottom of the esophagus, sort of like putting a hot dog in a bun. This creates a modest increase in pressure that is designed to be an effective barrier similar to the (ineffective) lower esophageal sphincter.

OK, cool! So, why doesn't everybody with significant heartburn go see their friendly neighborhood general surgeon and ask for one of these operations? Well, there are many reasons, but there are a few important things to keep in mind:

  1. Fundoplications should really be done only on the really, really symptomatic patient with oh-my-God GERD. The medications we have are really quite effective, and as much as it pains me to admit it, not everybody really needs an operation.
  2. There are a number of side effects to the operation. Most are minor, but need to be anticipated and patients have to understand that they are trading a set of severe symptoms for some that will need to be tolerated.
  3. Most importantly, the operation will sometimes fail --- the fundoplication falls apart or loses some of its efficacy over time, and patients get some or all of their symptoms back.

Getting back to the original point of the article and my post, it is this last point that is the major bone of contention between those evil gastroenterologists an us well-intentioned surgeons. The operation sometimes fails, with recurrence of symptoms --- but how often? Many patients return to their gastroenterologists with complaints of recurrent, or even persistent, symptoms --- but surgeons say this should happen on the order of 20-25% of the time, and some gastroenterologists state it happens nearly always! There is a widely discussed study published in JAMA (as a follow-up to a prior report published in NEJM) reviewing long-term results from a randomized trial of surgical vs. medical therapy for GERD in a cohort of VA patients that stated that an whopping 62% of patients who underwent Nissen fundoplication eventually took acid-reducing medications on a regular basis.

(Put in your own sound effects here --- surgeon scratching his head desperately trying to get the spirochetes to wake wake the few remaining neurons there...) OK. The surgeons feel like they are doing a good operation, but some (perhaps most?) patients get recurrent symptoms. But have the operations mechanically failed? Well, these guys actually studied their patients who came back with symptoms that suggested a failed fundoplication:
Methods We identified all patients from an existing database who had undergone pH monitoring for “recurrent heartburn” after fundoplication. These patients were then cross-referenced to another database, which recorded the outcomes for patients who had undergone a laparoscopic fundoplication. Patients complaining of dysphagia or other problems without heartburn were excluded from analysis.

Results Seventy-six patients were identified who met the inclusion criteria. Fifty-six (74%) of these had a normal 24-h pH study. Thirty-five patients (63%) with a normal pH study were on medication for heartburn at the time of referral. Three factors were found to be associated with an abnormal 24-h pH study: a partial fundoplication (P = 0.039), onset of symptoms 6 months or more after surgery (P < 0.001), and a good symptom response when antireflux medication was recommenced (P = 0.015).
Very interesting. In this study, almost 3/4 of the patients who had an antireflux operation and subsequently presented with complaints of recurrent symptoms were not refluxing! The true surgical failure rate in this selected symptomatic group was 26% --- and this builds on the evidence from a few prior studies that found a true surgical failure was found in 23-39% of similar patients. Interestingly, these authors found something that I have clearly seen (anecdotally, of course) through several years and many such surgeries --- the patients that complain of heartburn symptoms after an antireflux surgery that cannot be demonstrated to actually be refluxing most often state that acid-reducing medications provide them with no relief.

That leaves us with three unanswered questions:
  1. What, if anything, is causing these patients to complain of these symptoms? Er, I'm not really sure, but the authors propose a whole host of things, such as gastritis, gallbladder disease, irritable bowel syndrome, and functional dyspepsia. They say they're in the process of studying these patients as we speak.
  2. What about the patients who really do have a failed fundoplication? What can they do? Actually, although it is a considerably more complicated procedure, a truly failed fundoplication can (almost always) be redone, if the patient's symptoms are severe enough that they wish to travel down that road again.
  3. Most importantly, is it worth doing this operation if it has a significant risk of failing? I always feel guilty answering this question --- I could probably eat a chili cheese dog, chase it with rot gut tequila, and the be forced to watch Barbra Streisand movies for 8 hours in a row and not get heartburn. However, for the right patient, who has severe symptoms, and who has undergone an appropriate evaluation, a laparoscopic Nissen fundoplication is still a very good operation which provides a very good chance for long-term relief of symptoms.
That, at least, is my view. If you want the perspective of a GI doc ............... get a copy of this study to take with you. He may not read it, but it will be good for you to have something to read while you're doing the bowel prep for the colonoscopy he's sure to recommend.

Tuesday, May 15, 2007

Sudden Impact

There was a time when I watched TV occasionally. For some reason, the sight of David Letterman dropping a watermelon from a building made me smile. Plus, it's a great physics lesson --- terminal velocity, force of impact, and all that stuff I once knew quite well, but which has been relegated to a few rarely firing synapses in the recesses of my brain (I need to conserve the other space to remember the words to songs I learned in high school, along with every line from Monty Python and the Holy Grail). It also brings to mind the old saying "The bigger they come, the harder they fall."

Bigger = Harder Fall. Something to think about when part of your job involves taking care of trauma victims.

The overwhelming majority of trauma patients I see have suffered some sort of blunt trauma --- most frequently a motor vehicle accident (MVA). The opportunity to understand the basic principles of physics are always on display in MVAs --- the forces that affect the vehicles and their occupants can always be calculated....
(Impulse of force = Average force x change in time = mass x change in velocity; see, Fr. Deeves did teach me something)

Of course, one important component of these calculations is mass, and how it relates to momentum (momentum = mass x velocity). Any first grade boy can explain it to you, as he understands that dropping a brick his sister hurts more than dropping a Nerf ball. And any redneck knows that an F250 will plow over a Prius on the highway with ease.

But what happens the occupants of the F250 and Prius are a bit heftier than standard crash test dummies? Well, when you look at the mass part of the equation above, their increased mass generates a greater impulse of force ---- resulting in more bodily harm. This is the subject of a study published in this month's JACS : Body Mass Index and Outcomes in Critically Injured Blunt Trauma Patients: Weighing the Impact (gotta love that pun). The authors retrospectively reviewed the course of 1,543 patients with blunt trauma and an ISS (injury severity score) of 16 or greater. Out of that group, 30% were obese or morbidly obese; 24% had a BMI between 30-30.9, and 6% had a BMI of 40 or greater. Their findings included:

[1]A rising BMI is directly related to increases in hospital and ICU lengths of stay
>>morbidly obese patients had an LOS nearly twice that of patients with a normal BMI
>>ICU LOS more than doubled
[2]Pulmonary complications were more severe for those with obesity as well
>>they required longer ventilator support
>>ARDS, acute respiratory failure, and pneumonia were more prevalent in those with a higher BMI
[3]Just to add insult to injury, acute renal failure, MSOF, UTI, DVT, and decubitus ulcer formation were also seen more commonly in the morbidly obese blunt trauma patients.
[4]Interestingly, and seemingly incongruously, morbid obesity was not associated with a statistically significant increase in mortality.

So, what's the upshot? Elementary, my dear Watson! The larger the person, the more complicated their post-traumatic injury course. All of the issues that affect the morbidly obese patient in other emergency settings --- sleep apnea, diabetes, poor pulmonary toilet, increased risk for DVT and cardiac complications, etc. --- come into full bloom when they are impacted with an acute decelerating blunt trauma. And, although this article did not address it specifically, the larger the person, the greater the decelerating force they will experience, resulting in a higher risk for injury.

Just a little food for thought. Chew it over. Ruminate on it. Digest it. Just don't add it to your regular diet -- and skip the Cheetos too!

Thursday, May 10, 2007

Home schooling with martinis

Linguine spewing from my nose is not a pretty sight. Neither is a martini olive being coughed across the room like an ICBM. I know, because these things have happened at my dinner table the past few nights. Why? Because one of the Surglings came to dinner on successive evenings with tales of indoctrination by her teacher at L"C"PHS (local "conservative" public high school).

Disclaimer: I went to private (Catholic) grade schools and a private (Catholic) high school -- in Dallas at the time, it was well worth it.
The first night we were regaled with the story of how her LCPHS class was required to watch the AlGore Plea to Elect AlGore President Film. There was no discussion about the fact that this is felt by many to be a controversial subject. There was no discussion about the fact that there are scientists who disagree with Mr. Gore's conclusions. This was presented as 100% factual, and the students were told they would be tested on the material, just as they are tested on material in their textbooks.

OK. Lots of people are concerned about the phenomenon of global warming; the problem is that the subject is treated with a religious fervor that rivals anything that Jim Jones could foment. And a classroom, of all places, is where basic questions need to be discussed when things are less than crystal clear fact, such as ---
  • what's happening now, and how is it different from what's happened in the past?
  • what's likely to happen in the near future and beyond, and how do we estimate what will happen?
  • what are reasonable changes in public policy that can address the issue?
But of course, that would require that the discussion would be presented as something other than gospel truth. It would require spending another class period watching an alternative viewpoint which is freely available. It appears that this teacher feels there is more controversy surrounding the periodic table than the AlGorathon.

So, after wiping the table clean, we had a nice discussion about climate patterns, predictions, weather models, CO2 emissions, and the economic impact of significant public policy changes. In particular, we talked about simple economics --- supply of goods and demand --- a conversation that has never taken place in this school. I left out the juicy bits regarding the AlGoreMansion and his personal "carbon footprint," as well as the self-serving carbon "credits" he touts.

However, Mr. Teacher had more to offer. The next evening my daughter lets us know that by golly, somebody invented an engine a few years ago that gets over 100 mpg, and that the evil Texaco corporation bought it and buried it! Indignation was almost oozing from her pores. Who, I asked, was the source of such a fascinating tale? Why, it was the very same Mr. Teacher who brooked no discussion about global warming. After I replaced my olive, I gently informed her that I first heard a version of that rumor in 1968 -- when I was 6 -- and it was no more true today than it was then. Of course, being her father, I was not a very acceptable source for contradictory information. But, the magic of the internet allowed me to introduce her to the real truth.

Poor thing. She wanted to know if she should e-mail Mr. Teacher the information she learned from Snopes and from the Pacific Research Institute. I had to gently introduce her to the sad fact of what happens in too many classrooms today: although free discussion of ideas is a wonderful attribute of a healthy educational system, it does not exist in a classroom such as this --- and this man has her grade in his hands.

What, you may ask, does this man teach? Somebody who shows a lack of critical thinking skills might be teaching PE, maybe history, or perhaps an English class. Nope -- he teaches Biology. Honors Biology. And, I must admit, he is a carbon copy of my own honors biology teacher (yes, I can actually remember back that far, thankyouverymuch).