Saturday, March 31, 2007

Cesar Chavez Day

In lieu of Spring Break, we had Friday off for Cesar Chavez day. This is a Rembrandt painting of an anatomy lesson (Anatomie des Dr. Tulp), 1632.

Thursday, March 29, 2007

Liver Transplant Ethics

We had a lecture on the allocation of donated organs for transplant. It's a tricky subject. The supply of organs is extremely scarce compared to the demand. How do you decide who gets an organ first? For livers, once a patient is on the list, only the severity of his disease determines his likelihood of getting an organ. Indeed, a computer calculates a MELD score based on bilirubin, INR, and creatinine, values that reflect the prognosis of the disease. This makes some sense; those who need a liver the most get it (as long as they can survive the surgery, have no other comorbidities, etc.).

But imagine this scenario of two people. One is a 40-year-old mother of four who works at a bank and suffers from autoimmune hepatitis. This condition, probably genetically linked, has progressed to such severity that she is considered for the transplant list. She has great social and financial support. The second person is a 40-year-old man currently in prison serving a life sentence. His alcoholic cirrhosis has led him to end stage liver disease which requires a transplant. He has been sober for several years and went through rehab. While he does not have great social support, the prison system will cover a liver transplant and the subsequent medications.

Once someone is put on the list, only his or her MELD score will dictate how soon he or she gets an organ. If both go on the transplant list, the man will get a liver first because he suffers from a more severe disease. What kinds of things should go into the consideration for putting someone on the transplant list?

Clearly, it is unethical to bias medical attention to those with "perceived social worth," though this occurred in the past with kidney dialysis. We should not deny organs to prisoners by virtue of them being in jail. Instead, physicians look at likelihood of transplant success, focusing on other medical conditions, psychiatric concerns, likely compliance with anti-rejection medication, etc. It's really a tough ethical question what kinds of things matter in this decision when each organ is extraordinarily valuable.

Tuesday, March 27, 2007

Iodine Deficiency

Today, in histology lab, the professor asked, "Where in the United States do you see iodine deficiency goiter?" Since salt in the U.S. is all iodized, we were at a loss. His answer? "On tests."

Monday, March 26, 2007

The Alarming History of Medicine

I recently read The Alarming History of Medicine by Richard Gordon, a British doctor and writer. It's a collection of various amusing anecdotes about the history of medicine. A lot of the stories are quite fascinating, dealing with topics like anesthesia, infectious disease, and politics. However, the book is pretty poorly organized and difficult to follow. The writing style tries to be witty, but seldom succeeds (though it may be British humour, I don't know). More often though, the metaphors and rambling become a little grating and misleading. It's certainly not the best book I've read, but I suppose it's good for light reading for those interested in the history of medicine.

Sunday, March 25, 2007

Drinking


This was taken from one of our lectures on the liver. It's pretty interesting that the Egyptians wrote about the dangers of drinking.

Saturday, March 24, 2007

Vampires!


Porphyrias are diseases that result from disordered enzymes in heme biosynthesis (making hemoglobin for red blood cells). Porphyria cutanea tarda is one of these diseases, and its most striking manifestation is a sensitivity to sunlight. When exposed to sun, patients with the disease will have blistering, scarring, changes in pigmentation, and hair growth. Other symptoms include necrosis of the gums and iron overload.

Thus, some have proposed that the origin of vampire legends are based on this disease. Vampires are sensitive to light. With necrosis and retraction of the gums, the canine teeth appear larger. Since those with porphyrias are anemic (due to inability to synthesize heme), they appear pale. Perhaps they can even restore their blood by getting it from other people. According to Wikipedia, porphyrias might have been more common in small Transylvanian villages than elsewhere because of inbreeding.

I guess legends have to come from somewhere, and this interested me a lot. Perhaps vampires are just fictional exaggerations of this very tragic disease. Obviously, I don't want to suggest any connection between vampires and those with porphyria other than in the origin of this tale.

(Image: Edward Munch, Vampire. There were many results when I google imaged vampire, but this one was most artistic.)

Friday, March 23, 2007

Prometheus


We spent about a week or so on the liver. The liver is interesting because of its immense regenerative capacity. You can lose up to 70% of your liver and it'll grow right back. In fact, this makes living-donor liver transplants possible. You can donate one lobe of your liver to someone with cirrhosis or acute liver failure. You keep half, they get half. Within months, both of you will have completely regenerated livers. It's pretty amazing.

In the Greek myth of Prometheus, the Titan was punished by Zeus for giving fire to the humans. He was chained to Mt. Caucasus where an eagle named Ethon would eat his liver every day. Each night, Prometheus' liver would grow back just to be eaten by the eagle the next day. It is fascinating to wonder whether the Greeks knew about the regenerative ability of the liver. After all, why did they pick the liver? Why would it grow back each night? And when one thinks about the origins of medicine, one might think all the way back to the Greeks.

(Image: Prometheus Bound by Nicolas-S├ębastien Adam, 1762)

Thursday, March 22, 2007

Separating Medicine and Personal Life

I wrote a post a few days ago about treating family members. That got me thinking, should a doctor separate what he does in the hospital from what he does at home? This wouldn't be easy. Some jobs may be different in this respect than others. If you code for a software company or crunch numbers in a cubicle or work as a cashier, it seems like there is a definite demarcation between the things you do at work and the things you do at home. But a doctor deals with things of such emotional weight. There must be events - saving someone's life, watching someone die - that you can't just leave behind at work and forget at home. I guess things are a little different for me right now; being a student is my life. The distinction between school and non-school is pretty blurry; when I go home, I have to study or read or prepare. Is this going to be the same when I become a doctor? I wonder. On the other hand, doctors have to have some emotional distance; after some time dealing with issues of health and disability, life and death, it seems like doctors must develop desensitization to the emotional impact of what they do. This is necessary for the physician's well-being as well as the physician's objectivity. I'm just wondering how and when I can come to terms with the emotional events of a doctor's day-to-day life.

Tuesday, March 20, 2007

Nutrition II

We get some basic lectures on nutrition with a heavy focus on what we need to know as doctors. I like that; nutrition is such a complicated, pervasive, and fashionable subject that we could easily get lost in trying to figure out fad diets and the latest trends. While that would certainly be interesting, I don't think it's essential to medical care. I'm sure many people out there know far more nutrition than I do. Instead, we focus on treating diseases like obesity and vitamin deficiencies. There are so many different vitamins, minerals, and organic compounds that we need, it often impresses me that most people, with such diverse backgrounds, diets, and eating habits, can satisfy the basic needs of the body. I certainly don't know what foods I eat have folate, but somehow, I am not folate deficient. Hopefully, these nutrition lectures will give me a greater awareness of what I eat and encourage me to be more healthy. I also expect that I will give nutrition a little more weight in the future when I consider what may be wrong with a patient or how to treat a disease.

Sunday, March 18, 2007

Nutrition I

"If you succeed in tipping a cow only partway, such that only one of its feet is still on the ground, you have created lean beef. Such a feat is well done. Naturally, being outside, the cow is unstable. When it falls over, it becomes ground beef." - from a Wikipedia entry on "Cow Tipping," which has since then been edited.

Saturday, March 17, 2007

The Historical Achievement of Both Medicine and Surgery

"Good, but limited. Ashes to ashes, dust to dust, if the cancer don't get us the arteriosclerosis must." - Richard Gordon, The Alarming History of Medicine

Thursday, March 15, 2007

Treating Family Members

A recent JAMA article discussed the issue of doctors treating people they have personal ties with. These can be familial or intimate ties, but also close social ties (as in friends). In general, these professional relationships are highly discouraged. Obstetricians don't deliver their own babies. Doctors don't see friends and patients in the clinic or hospital setting. Indeed, doctors don't diagnose and treat themselves. Often, the reason cited is a lack of objectivity. You don't think it could be cancer, because it's your husband, and he couldn't possibly have cancer. You can't imagine your child has a genetic disease; neither you nor your spouse has it. These thoughts get in the way of patient care. Perhaps the patient-doctor relationship would be blurred with the friendship; perhaps things would be awkward outside the clinic. Or what if the patient had a terminal illness or a grave disease; how would this affect the relationship?

On the other hand, I think that knowing someone well gives you more insight than anyone else. You already have a strong bond with the other person; you can trust them, you know how much they exercise or what they eat. You're part of their social support, you know they'll be more compliant with their medications, you have a driving incentive to give them the optimal care. Indeed, this article discussed doctors in small towns where everyone knows each other. The doctors will take care of patients and then see them that evening at a social event. They will have cared for generations of families. Is this a barrier to good patient care? I doubt it. The patients like it. The doctor's emotional ties propel the physician-patient relationship forward. And on a practical level, it's hard to find a solution to delivering health care to small towns.

Wednesday, March 14, 2007

High School Music

As identified by the 1999 hit song "No Scrubs," doctors can't seem to get any TLC.

Monday, March 12, 2007

Sunday, March 11, 2007

City by the Bay


"Mr. Whirly had a catastrophic incident / He fell into the city by the bay / He liquidated his estate / Now he sleeps upon the Haight / Panhandling misery." (Green Day - Misery).

When I first heard this song, I had no idea what it was talking about. I encountered it in an undergrad class called "Social Dances of North America 2" where it was played as a schottische, a Bohemian folk dance. Amazing, huh?

San Francisco couldn't be further from misery. True, the fog and the traffic and the weather can get you down sometimes. But I really like the city. It has its own personality, its own attitude. There are so many things to try, so many things to do. It's a beautiful place, with hidden shops and fascinating panhandlers and cultural secrets. It's wonderful to have the time to try unique restaurants (Burmese food anyone?) and dessert places (there's a cool place called Creations on Geary). A few of my friends from undergrad live in the city and spending time with them is great; sometimes, I just need to get away from this medical world. I love hanging out with friends over at 145 Irving, watching a movie, eating ice cream, and not worrying at all about nutrition and metabolism. But, I suppose with the upcoming test, we may again find ourselves sequestered in libraries and tomes of knowledge.

Saturday, March 10, 2007

Biochem


We just got a taste of some biochem last week. It seemed to come out of nowhere, but the purpose was to prepare us for learning about anemias, some of which are related to GI etiology (bleeds and nutritional deficits). Oddly enough, we started with the pentose phosphate pathway ("pentose phosphate mess") and nucleotide synthesis. Then we covered the importance of iron, folate, and Vitamin B12 - generally the harder things in biochem.

I actually really like biochem. I got a decent background in it as an undergrad, and organic chemistry is a lot of fun (maybe not mechanisms though). But it is a bit daunting for a lot of people as this is our first immersion into metabolic pathways. We're only touching the surface though. We don't have to memorize much, and we only focus on steps that are affected by human disease. That makes a lot of sense as I doubt most doctors can really tell you the molecules in glycolysis, but they may be able to describe the symptoms of glucose-6-phosphate dehydrogenase deficiency (it's an X-linked disease that causes hemolytic anemia if you eat fava beans among other things).

Friday, March 09, 2007

Atul Gawande

Here is a link to Harvard Medical School's 2005 Commencement Address which was given by Atul Gawande. It's a humorous, quite insightful speech, and I think it's a very good read, especially if you want to get an idea of how Complications is written.

http://www.hms.harvard.edu/news/grad2005.html

Thursday, March 08, 2007

Complications


I recently reread the book Complications by Atul Gawande. He is a general surgeon and assistant professor at Harvard who writes for The New Yorker. This book is a series of narrative essays on various issues in medicine: training in procedures, conferences, flesh-eating bacteria. I had heard and known about many of these topics, but his writing is eloquent, poignant, and engaging. I really think his rhetoric and narrative bring this book to a new level and makes the reader think. He is able to combine scientific evidence with patient cases in an easily-readable fashion for the layperson. I highly recommend this book to anyone interested in medicine.

Wednesday, March 07, 2007

Foundations of Scientific Inquiry

My other elective this quarter is Foundations of Scientific Inquiry, a class for those interested in scientific research. I have mixed feelings about this course. The first half of the course deals with some logistics of research: how to choose a mentor and define a project, how to write a grant, how to find funding for this summer. We also cover basic methods of investigation like molecular biology and genetic techniques. The second half of the course is similar to a journal club; we read papers and often the PI will come in and discuss them with us.

A course like this is critical for medical students, especially at a high-powered research institution where students are interested in basic science, translational, or clinical research. We don't get very much of this in our core curriculum (we're never required to read any journal articles, for example). The elective is great to introduce us to faculty members who we may consider working with. It also gives us exposure to a wide range of research.

However, I also think that the course can explore things in greater depth. For example, I think less time should be spent on the first half of the course, in covering Western blots and ion exchange chromatography and transgenic mice (though I concede that very little of this is formally taught in the core curriculum). I appreciated the time spent on how to find a project and funding, but I'm really more interested in learning how to think like a scientist. This comes out in the second half of the course, but since it is an elective, people take the course less seriously and may or may not do the reading. The discussions aren't as rich as I hoped they would be. But I am learning a lot and I enjoy that.

Tuesday, March 06, 2007

The Cost of a Pap Smear

"A year is the time it takes for the earth to make a complete revolution around the sun. It has very little to do with the cervix."

I heard an excellent talk today about Dr. Sawaya for the Clinical Sciences elective. He researches the societal cost-benefit relationships of screening tests like the Pap smear. For a long time, women over 18 were encouraged to get annual Pap smears, a test that looks for cervical cell dysplasia, a precursor to cancer. This translates to a lot of Pap smears, far more than is done in any other country.

In analyzing data from a CDC study, Dr. Sawaya found that women who have three consecutive normal Pap smears may not need further annual tests; in this case, tests every three years may be nearly as effective. If Pap smears are done annually, the rate of false positives exceeds that of true positives, and the "cost" (financial, risk during further tests like colposcopy, stress and anxiety) may not justify such a regimen in a non-high-risk woman. If we do Pap smears every three years rather than annually, we may miss 12 cases of cervical cell dysplasia per 100,000 people and 1 cancer per 100,000 people. However, we gain on the order of a million dollars annually per 100,000 people. Cervical cancer takes something like ten years to develop from cervical cell dysplasia so annual vigilance may not seem completely rational.

In the end, no matter how many tests we do, we will miss some people. The question is how low our threshold should be. There are many policy decision-analysis models to look at this. Should we invest over a million dollars to catch 12 people per 100,000 with worrying cervical dysplasia, one of whom will progress to cervical cancer? I'm not convinced. We are a society that does too many tests without regard to the general health of the health care system.

Sunday, March 04, 2007

Medical Mandarin

I'm taking an elective on elementary medical mandarin. It's fun, but I'm not sure how useful it is to me. We have five 2-hour sessions, and it is hard to pick up a lot of a language in that amount of time. The class is geared mostly to those with a limited knowledge of mandarin. Since I speak it fluently, the class isn't particularly directed at me. However, I wanted to learn some of the medical terms and phrases that I don't know.

I feel that the class is fairly fast-paced for those who do not know the language. We do a little pinyin (which I don't know, since I learned Chinese by characters) and pronunciation. We cover common everyday expressions and phrases. Then we do a little bit of medical-oriented vocabulary. In general, it's enjoyable because one of my pharmacy friends from high school is taking it; both of us went to Chinese school together as kids. In any case, though I haven't learned a great deal, I think it's good to hear medical mandarin being spoken and to practice it.

Thursday, March 01, 2007

M&N

Finally, a non-ethics post. Recently, we started our metabolism and nutrition block. This 8-week block focuses on gastroenterology and endocrinology. So far, we've had quite a bit of anatomy, reviewing a lot of the peritoneum as well as upper GI tract. The anatomy labs aren't too bad, though I still find nerves and vessels difficult. We did get a chance to practice suturing on intestinal tissue, which was good. It takes me a bit of practice to get comfortable with those skills.

Gastroenterology also has an unfortunate amount of histology. I'm neither very good nor incredibly interested in histology, though I recognize its importance. We've had a few physiology lectures, but those haven't been too difficult. We're just starting some of the pathology and disease processes that can affect the GI tract. It should be an interesting block; I don't know too much about these organ systems. However, I can feel the grind wearing most of us down slowly.