Author: MarkH

  • Finally, an explanation for my sneezing

    Here I thought I was the only one but apparently photic sneezing has received enough attention to get researchers interested in it. Apparently it’s an ancient problem:

    Aristotle mused about why one sneezes more after looking at the sun in The Book of Problems: “Why does the heat of the sun provoke sneezing?” He surmised that the heat of the sun on the nose was probably responsible.

    Some 2 ,000 years later, in the early 17th century, English philosopher Francis Bacon neatly refuted that idea by stepping into the sun with his eyes closed–the heat was still there, but the sneeze was not (a compact demonstration of the fledgling scientific method). Bacon’s best guess was that the sun’s light made the eyes water, and then that moisture (“braine humour,” literally) seeped into and irritated the nose.

    Humours aside, Bacon’s moisture hypothesis seemed quite reasonable until our modern understanding of physiology made it clear that the sneeze happens too quickly after light exposure to be the result of the comparatively sluggish tear ducts. So neurology steps in: Most experts now agree that crossed wires in the brain are probably responsible for the photic sneeze reflex.

    It’s apparently an autosomal dominant trait, which would explain why other members of my family have the reflex too. Anyone else a photic sneezer?

  • Skeptics' Circle Number 78 – The Skeptical Surfer

    This week’s circle is at skeptical surfer’s blog. Although I think Christian has made an error or two in his evaluation of the latest NHANES studies and what they say about obesity. For one, obesity has always been 30+ BMI, overweight was changed from 27 to 25 by one government agency responsible for surveillance of disease (CDC) to conform with other agencies’ metrics. Further as I explained, the NHANES studies are hardly single variable, and don’t take into account a change in medical culture towards better secondary prevention of comorbidity in the overweight and obese. It’s all good though. I appreciate an honest effort.

  • Wounds!

    Despite the best attempts of the New York Times Wellness Blog to get me fired, I’m still here and doing fine. Somehow a post about how impressed I was with surgery, the professionals that practice it, and how many of my preconceptions about surgeons were incorrect, got all turned around into some “peak behind the curtain” into the secrets of the medical profession. This is terribly absurd and the article made a hash out of what I was trying to say. I was trying to relate some of the shock one experiences going from an academic setting into a clinical one for the first time, as a reminder to those who have done this before, and maybe preparation for those who have yet to make the jump. None of these things are secrets, and all could be culled from watching about 15 minutes of the Discovery channel or Scrubs.

    But the confusion of some individuals over what I was trying to communicate is still my problem, even if I was quoted all out of context. Clearly the biggest issue is the change in audience, my sb audience includes a lot of scientists and doctors, and the way I write is somewhat geared to this group. Thus you’ll notice in my comments mostly positive responses – especially from medical professionals like Orac, PalMD and various others. When the NYT expands my audience to a group of people who don’t know my writing, my assumptions or my more egregious stylistic shortcuts, it is not surprising there was some confusion and hurt feelings, not to mention some people with absolutely no sense of humor.

    This does not mean that there is no problem however, ultimately this is a sign that I need to remember that I am writing in a public arena and need to be more careful with the assumptions I make about my audience on any given day. Rather than clamming up for the next couple of decades until I’m tenured, instead I’m going to use this as an opportunity to broaden the appeal of the blog and help explain to a wider audience what evidence based medicine is, the process of learning it, and why I think medicine the best career in the world. Writing this way will help educate people about medicine and how its practiced, and at the same time improve my knowledge of medicine with the goal of making me a better doctor one day. So, back to basics.

    First, an explanation of the role of a medical student in the arena of patient care. Medical students are being introduced into the profession of medicine. To accomplish this they take two years of some of the most arduous training imaginable, intensively learning about anatomy, physiology, pharmacology, biochemistry, genetics, pathology, microbiology, physical exam, history taking, and all the other knowledge that makes up the foundation of clinical knowledge. By the third year, which is what I am currently in, you have accumulated more knowledge in two years than you probably have in your entire life. You are tested, retested, observed, corrected, and tested again and after all this work you get the incredible privilege of participating in patient care in your second two years of med school. This does not mean your first week of patient care is any less of a shock to the system – it is very much different from the purely academic pursuit of medicine – it is more of an apprenticeship in which you learn by doing and is certainly the most important part of learning to be a clinician. At this point you are participating in patient care, usually at an academic setting, and you see patients, take histories and physicals, learn how medical decisions are made in the care of individual patients, and in the case of surgery, observe how operations are performed. While you are an important part of the patient care team, you are not responsible for clinical decisions at this point and are at the bottom of the proverbial totem pole. You work with interns, residents and attendings who are ultimately responsible for medical decisions. For the most part, you observe, participate, tell them what you would do, and then wait patiently as these more experienced clinicians explain why you are right or wrong and what is the correct course of action. It is training to develop clinical judgement and competence in patient care. Further, when I say that I “scrub in” to a surgery, it means that I am allowed into the sterile field (after scrubbing, gowning, gloving etc.) and am given the privilege of watching surgery up close. If you’re lucky you may get to participate, but in a very limited capacity, never beyond your abilities (usually just holding instruments, aiming a camera, applying traction, suction etc), always under the supervision of someone with between 5 and 40 years more experience than you, and in a very controlled environment. Always paramount is the patient’s well-being, and if it is ever in question you quickly find yourself shuffled back behind the doctors who are doing the very difficult and demanding work. Before you even step into the room one must remember the student has years of training to understand the pathology and anatomy of the case, the student has read up on the patients’ specific case, and has reviewed the surgical procedure, relevant pathology, anatomy etc. Before you work with patient on a medicine rotation you’ve done similar prep, and throughout the case are studying the patient’s case, lab results, textbooks of medicine, the scientific literature, etc., as part of your training. When you graduate from medical school and become an intern and then a resident you are still training for about 3-5 more years, you become directly responsible for patient care, and are under the supervision of an attending physician. This structure is ultimately very successful and academic medical centers provide the best medical treatment in the country, attract bright people, take all kinds of cases (the ones many other hospitals simply can’t handle), and constantly push the boundaries of medicine.

    Now, onto the fun part. A clinical case. This is how we learn medicine, as being social animals, it’s almost always easier to remember medicine in the context of a person. You’ll always remember medical facts and treatments better if they are associated with an actual human being. And this is, of course, an artificial teaching case having nothing to do with an actual individual. I had a post all prepared describing a complicated procedure, but since we’re starting from basics, let’s begin with wounds.

    The patient is a 52 year old construction worker who suffered from an open fracture (bones sticking out of the skin) of his left radius and ulna (bones of the forearm) from on-the-job accident. He was taken to the ER, his arm was evaluated with a plain X-ray film, and the break was cleaned, reduced, and set in the OR. He received prophylactic cephalosporin antibiotics before the surgery. 24 hours later he is on your floor, admitted to your service, and he complains of chills, and severe burning pain at the site of his incision. The patient is alert and oriented to time, place, and person, but is diaphoretic (sweating), pale and in some distress. He has a fever of 39.2, BP 140/90, and his heart rate 110 beats per minute. An examination of the arm reveals a brown, weeping wound at site of the repair, the arm is warm to the touch, and acutely painful. Physical exam and review of systems is otherwise unremarkable. Labs show an elevated white count. He has a history of type II diabetes and hypertension.

    What do you do?
    A) Treat empirically with a broad spectrum IV antibiotic like Cipro and culture the bacteria for a definitive diagnosis and sensitivity testing.
    B) Clean and debride the wound.
    C) Change the dressing and wait for the wound to heal naturally.
    D) Send the patient back to surgery to debride (clean) the wound and start therapy with penicillin and clindamycin.
    (more…)

  • A week of surgery – some impressions

    One only has to be minimally involved in a surgical procedure to understand the appeal of this profession. It is instantly gratifying and very rewarding to be able to just fix something. That, working under time pressure and mixture of physical and mental skill make it a very exciting way to practice medicine.

    So after a week of this, and just getting off call around 1:00 this AM after scrubbing in on a liver transplant I’ll tell you what has surprised me about surgery so far, and some of the things I didn’t realize going in.
    (more…)

  • My feet hurt

    Eight hours standing in a single spot, how do surgeons do it? I’m hoping my endurance will build, especially knowing that some of the procedures I’m going to see in the next few weeks such as the “Whipple” or pancreaticoduodenectomy may take twice as long.

    The good news is that I have lucked into working with great people – the misbehavior of surgeons is greatly exaggerated – and have learned lots of interesting things. The coolest yet was running the camera on a laparoscopic or “keyhole” surgery – it looked something like this.

    Although what we did was more complicated (and harder to reach) it was both physically and mentally challenging. Basically, you are operating a camera in a 3 dimensional space, and the hand movements that will direct the position of the camera are reversed (usually). It’s a little bit like flying a plane, meanwhile, you’re standing for hours in a single spot, unable to lean on anything, maintaining a sterile field, and trying to track the position of the surgeon based on the movements of the instruments and a fair amount of mind-reading. It goes from exciting, to grueling pretty rapidly. Meanwhile the attending is standing in the same spot, running everything, not even bitching at me when I end up off target, perfectly content, like a stone wall, while my feet are killing me. How do they do it?

    More soon.

  • Ask A Scienceblogger – Why don't they make a birth control pill for men?

    i-133b9fea8ea6b307d8c9133b7f3e23bf-dice.jpg This time the Ask a Scienceblogger Challenge is to explain why a male contraceptive pill does not exist.

    Good question! It’s because medical researchers are all sexist bastards. Didn’t you know?

    Actually that’s only part of the reason. Research into hormonal or pharmaceutical contraception for men is a hot topic. Male hormonal contraception is actually fairly effective. Using a combination of testosterone and other hormones to suppress the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary you can, after several months, prevent men from making sperm. For the men that respond (not all do), this treatment is highly effective as a contraceptive method. But the problems are delivery and efficacy. If you first screen men to see if they respond, then it is highly effective. But it doesn’t work on everyone: unlike the pill, you have to inject these drugs, put in implants or use a patch for delivery. This makes it far less attractive than the oral contraceptive pill for women, which is 98% effective when usedcorrectly and works with few exceptions. In the future, researchers may develop a more effective delivery and screening system for men that would allow them to more reliably assess the efficacy of the treatment.

    Sexism has played some role in the long delay in the development of male contraception. But these days the far more important issues are those of physiology and capitalism. Women produce one egg a month and have a biologically built-in mechanism for preventing ovulation. Men, on the other hand, are sperm machines, producing an overabundance of genetic delivery vehicles from adolescence until death–with no simple mechanism to interrupt production. That’s why barrier methods, such as condoms, will likely remain preferable even after the development of hormonal birth control for men as they are highly effective and also prevent STD transmission. And for women, the pill (especially in lower-dose modern formulations) is safe, effective, and very well tolerated.

    The second problem, that of capitalism, refers to the difficulty in developing a market for male contraception and thus the limited incentive for their production. It will be difficult for drug companies to sell a formulation for men that alters their hormones, lowers their sperm count (a cultural barrier), and requires doctors visits, injections, sperm counts, etc., when highly effective alternatives already exist. Many women will also likely prefer to remain in control of contraception because it’s their body, their health, and because men are liars. The capitalist barrier may be even more significant than the physiological obstacles.

    Male hormonal birth control options will probably be offered within a decade. But they will likely be a niche market, limited to people in committed monogamous relationships, or for the partners of women who can’t tolerate the pill, and thus, not widely adopted.

  • Surgery!

    This new year is shaping up to be pretty exciting, and part of the changes in my life will be reflected in what I write about on the blog. First let me explain how the MD/PhD program I’m in works, and where I am in it.

    The Medical Science Training Program (MSTP) or MD/PhD program is designed to promote bench-to-bedside or translational research. The idea is that if you take medical students and give them a PhD as part of their education they will be more likely to take science from the basic literature (bench research) and translate it to medical care (bedside research) or at least do research that is more applicable to clinical research. In practice this ideal is not always achieved, but we try. This program is funded by a grant from the NIH, and between 2-10 such positions exist at most medical schools.

    The program starts with students doing two years of medical school, which at most U.S. universities consists of the basic science portion of the medical curriculum. In the first two years you learn biochemistry, physiology, anatomy, histology, pathology, microbiology, pharmacology, genetics, psychiatry, etc. and at the same time are introduced into clinical medicine, differential diagnosis, taking patient histories, physical exam, and all the other skills you need to become a medical doctor.

    After you complete these two years, and take the first of the national standardized tests to check and make sure you’re not a total incompetent, MSTP students then go into graduate school. Yes, some intelligent people actually think this is a good idea and enter this program. Luckily, you get a good deal of credit to your graduate classes (or substitute some graduate classes in medical school) and for the most part go straight into lab work. Then it’s the standard grad school spiel which I explained previously. Briefly, you work in a lab, you struggle, eventually figure out what the hell you’re doing, and then write a thesis. Now the fun part, after being separated from the first two years of medical school by between 3 and 13 years you get tossed into patient care for the medical school third year.

    The third and fourth years, referred to as “the wards”, is more like a medical apprenticeship. You spend between 4 and 8 weeks on a variety of wards learning the full breadth of medical practice. These consist of family practice, surgery, psychiatry, medicine (ICU, infectious disease, slumming around the hospital etc.), neurology, pediatrics and OB/GYN, and whatever electives you decide you are interested in. This is when you really learn medicine and how to apply your clinical knowledge to the actual treatment of sick human beings.

    I’ve spent the last month studying, working with doctors to get my clinical skills back, and generally freaking out in preparation for tomorrow, my first day on the wards. And guess which I’m doing first!
    (more…)

  • The End of the James Randi Challenge

    After ten years the James Randi Educational Foundation is discontinuing its 1 million dollar paranormal challenge.

    The James Randi Educational Foundation Million-Dollar Challenge will be discontinued 24 months from this coming March 6th, and those prize funds will then be available to generally add to our flexibility. This move will free us to do many more projects, which will be announced at that time.

    I’m disappointed, because that means in two years we will lose one of the best anti-woo tools in the arsenal. That is, the offer of 1 million dollars to any woomeister who can prove their paranormal abilities are real in a controlled scientific test in order to shut them up. Otherwise it wasn’t that helpful, as the real prominent fakers knew better than to actually put their livelihood on the line as they describe:

    Our expectations at first were that we’d attract major personalities by this means, but they’ve avoided having to take the test by simply not applying; those who have actually applied are generally honestly self-deluded persons who have difficulty stating what they can do, which can be understood if they really don’t know what they’re experiencing; we at JREF have gone through involved procedures to help them recognize their problems. Usually, they have indicated that they don’t know what real scientific rules are, when it comes down to their actually being properly tested.

    But for two more years at least we’ve still got this ace up our sleeve. There is still time to apply all you woos out there!

    This means that all those wishing to be claimants are required to get their applications in before the deadline, properly filled out and notarized as described in the published rules.

    Ten years is long enough to wait. The hundreds of poorly-constructed applications, and the endless hours of phone, e-mail, and in-person discussions we’ve had to suffer through, will be things of the past, for us at the JREF.

    Those who believe they have mystic powers now have two full years to apply… Let’s see what happens.

  • Skeptics' Circle Number 77 – White Coat Underground

    White Coat Underground has the overmedicalized edition. I’m pleased to see Happy Jihad House of Pancakes arguing for more skepticism in the humanities as part of the circle. And a great post on epidemiology and autism from Andrea.

    Orac had some important things to say about consensus, and just to clarify my position on how a skeptic should regard consensus it’s simple. It is a sign of crankery to attack consensus as a concept, for example see this nonsense from creationist John West whining about consensus on evolution. However, a big part of being a scientist is challenging various consensus views (usually consensus views of lower strength than what the cranks are after – another sign). This is why so many crank arguments about consensus are so laughable to people who have actually worked in science. You don’t get published for writing up studies repeating the same results endlessly, science rewards novelty and new findings. If you have high-quality data that contradicts the consensus, you should attack it and your paper will likely be widely read. While it’s true that in many fields an old guard will defend their view to the death, the history of science is that of the data ultimately saving the day. It’s perfectly OK to attack a specific scientific consensus but you do it by publishing papers, and arguing with legitimate data and high-quality argument. A crank is one who attacks the mere idea of consensus, who acts through political channels to try and change scientific knowledge, who tries to subvert consensus with no data except maybe some cherry-picked nonsense,who uses a bunch of conspiracy theories to explain why no one believes them, and all the while cries persecution if they’re not immediately believed or if their BS isn’t a mandatory part of public school curricula.

    Just to clarify.

    Finally, of note today, Steven Novella has started a new blog Science Based Medicine that will likely be worthy of note.

  • Values Voters and Neo Nazis

    I see that I’m in good company in my curiosity about why Ron Paul enjoys so much crank magnetism. And his crank magnetism and appeal to racist groups can’t be denied. Here for instance, is Ron Paul posing with Don Black, culled from the neo-nazi Stormfront website:

    i-7cd49f3c65eacc9dfe3357dfd02dbfe9-20071220RonPaulDonBlack.jpg

    Now, I think its unlikely Ron Paul knew who this was when he posed for this shot, but between this and their endorsement of Paul on Stormfront radio, I think it’s pretty well confirmed who their candidate is. Also note, this picture was taken at the “Values Voters Presidential Debate” just as a reminder of who “Values Voters” debates appeal to.

    One of my commenters, quoting Digby, made the point that Ron Paul support isn’t so much a political position as a sign of disaffection. Based on the wide political spectrum of cranks that seem to think this anti-government radical is their guy (including the poorly-named Reason magazine as PZ points out) I think Digby’s assessment is the correct one. Cranks recognize one of their own.

    I’m not actually concerned about Ron Paul’s candidacy, I believe his appeal is overblown as any real exposure to his beliefs will turn off the 95% who realize such a fervently anti-government radical libertarian would be the worst candidate one could conceivably elect. He scores easy points at these debates mocking the rather pathetic Republican presidential field and appealing to the people’s populist sentiments, but underneath this facade is a crank, and crank candidates rarely poll higher than about 5-10% (and I include Nader in this category – deal with it). So while it’s been fun mocking this also-ran all week, I don’t think we’ll be seeing much more of this guy after Iowa and New Hampshire.