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Archive for Surgical Procedures

Human subjects protections and research ethics: Where the rubber hits the road for science-based medicine

Arguably the most difficult aspect of science-based medicine is where the rubber hits the road, so to speak. That’s where scientists and physicians take the results of preclinical studies performed in vitro in biochemical assays and cell culture models and in vivo in animal models to humans. There are numerous reasons for this, not the least of which that preclinical models, contrary to what animal rights activists would like you to believe, do not predict human responses to new therapeutic agents as much as we would like. However, the single biggest reason that we cannot answer questions in human studies as easily as we can in cell culture and animal studies is ethics. Of course, answering questions using cell culture and animal studies is not “easy,” either, but performing studies using human beings as subjects is an order of magnitude (at least) more difficult because the potential to cause harm exists, and if harm is caused by the experimental treatment under study, that harm will be done to human beings, rather than cells in a dish or mice bred for research.

The “gold standard” type of study that we do to test the efficacy of a new drug is known as the randomized, placebo-controlled, double-blinded study, often abbreviated RCT. Indeed, this remains the gold standard and is accorded the highest level of “power” in the framework of evidence-based medicine. Of course, as we have argued time and time again, using the RCT to test therapies that are incredibly implausible on a strictly scientific basis (homeopathy or reiki, for instance) inevitably leads to numerous “false positives” in which the therapy appears to produce results statistically significantly better than the control. John Ioannidis has done numerous clever analyses that demonstrate how easily clinical research is led astray if it is not grounded in scientific plausibility. Indeed, the probability of false positive studies increases, the more improbable the modality. It is for these very reasons that we have proposed the concept of science-based medicine, which takes into account estimates of prior probability based on preclinical studies and basic scientific principles, rather than evidence-based medicine, which does not. Indeed, Wally Sampson has even proposed a “plausibility scale” for rating RCTs, and Steve Novella has pointed out how difficult it can be to interpret the medical literature.
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Posted in: Clinical Trials, Medical Ethics, Politics and Regulation, Surgical Procedures, Vaccines

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Is IV Sedation Over-Used?

We criticize alternative medicine for not being evidence-based, and they criticize conventional medicine in turn, saying that much of what conventional medicine does is not based on evidence either. Sometimes that criticism is justified. I have run across a conventional practice that I suspect began because it sounded like a good idea, but that never was adequately tested and is not carefully thought out for individual patients.

I recently had a bone marrow aspiration. The written instructions said not to eat or drink for 6 hours before the procedure, to bring someone to drive me home, and to expect an IV. I suspected from these instructions that they were planning to use IV sedation, and I was right.

I questioned the need for sedation. I am prejudiced about bone marrow aspirations. I observed several and did one myself during my internship. When I had finished, the patient asked me when I was going to start. We did the procedure at the patient’s bedside in a multi-bed ward with no sedation, only local anesthesia. So my prejudice was that the procedure was no big deal and was not terribly painful.

I can imagine that some patients may be terrified by the idea of a needle going into their bone and may want to be sedated and not remember the experience. But I was not anxious about it, and I saw no need for the fentanyl and Versed they wanted to give me. I figured it would only prolong my time in the hospital, produce amnesia, expose me to a small risk of adverse effects, and leave me groggy; so I asked to opt out. They readily agreed – although they did keep asking me if I was really sure I didn’t want it. They would not have offered the option of no sedation if I had not known to ask. (more…)

Posted in: Pharmaceuticals, Surgical Procedures

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Alternative medicine use and breast cancer

Of all the posts I and my cobloggers have written for SBM over the last 15 months, most provoke relatively few comments. However, a few stand out for having provoked hundreds of comments. The very first post that provoked hundreds of comments was Harriet’s excellent discussion of the International Network of Cholesterol Skeptics. In fact, Harriet seems to be quite good at writing posts that provoke a lot of comment, as another of her posts, specifically the one in which she discussed circumcision, also garnered hundreds of comments. However, to my great surprise, the one post that stands out as having received the most comments thus far in the history of SBM is one that I wrote. Specifically, it was a post I called Death by “alternative” medicine: Who’s to blame?, which has collected an astonishing 611 comments thus far. The topic of the post was a case report that I had heard while visiting the tumor board of an affiliate of my former cancer center describing a young woman who had rejected conventional therapy for an eminently treatable breast cancer and then returned two or three years later with a large, nasty tumor that was much more difficult to treat and possibly metastatic to the bone, which would make it no longer even potentially curable. My discussion centered on what the obligation of a physician is to such patients who utterly refuse the science- and evidence-based medicine that we know to be able to cure them of a potentially fatal disease, and I was not only surprised but somewhat taken aback by the vehemence of the discussion.

Since that post, I’ve always been meaning to take a look at what, exactly, the effect of choosing “alternative” medicine over “conventional” medicine is on the odds of survival for breast cancer patients. Even though intuitively one would hypothesize that refusing scientific medicine and relying on placebo medicine instead would have a detrimental effect on survival, it turns out that this question is not as easy to answer as you might think. For example, if you do a search on PubMed using terms like “alternative medicine,” “breast cancer,” and “survival,” the vast majority of the hits will be studies of complementary and alternative medicine (CAM) and breast cancer with little reference to what possible effect these therapies might have on survival. I can envision several reasons for this, the first being that–thankfully–relatively few women actually use alternative medicine exclusively to treat their breast cancer. Also, those that do probably drop off the radar screen of their science-based practitioners, and it is difficult, if not impossible, to capture data regarding their outcomes, given that they all too often stick with their alternative healers until the end. True, they may pop up again in their surgeon’s or primary care doctor’s office with huge, fungating tumors, only to be told that they have to undergo chemotherapy to shrink the tumor before any surgery is possible, after which they will often disappear again. Another important reason is that the natural history of breast cancer is extremely variable, from nasty, aggressive tumors that kill within months to indolent, slow-growing tumors that, even when metastatic, women can survive with for several years. (It is, of course, these women who usually show up in “alternative medicine” testimonials, because they can survive a long time with little or no treatment before their tumors progress.)
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Posted in: Cancer, Herbs & Supplements, Science and Medicine, Surgical Procedures

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When fraud undermines science-based medicine

The overriding them, the raison d’être if you will, of this blog is science-based medicine. However, it goes beyond that in that we here at SBM believe that science- and evidence-based medicine is the best medicine. It’s more than the best medicine, though; it’s the best strategy for medicine to improve therapy for our patients. We frequently contrast science-based medicine with various forms of “complementary and alternative medicine,” specifically pointing out that SBM changes its practices as new science and new evidence mandates it while CAM tends to rely on ancient, vitalistic, pre-scientific or pre-modern scientific beliefs about how disease occurs as the basis for its therapies. Although it may be painfully slow and frustrating at times and even though there may be major stumbles along the way, the overall course of SBM over the last century has in general been to produce ever more effective therapies and to discard therapies that are either ineffective or whose risk-benefit ratios are insufficiently favorable. The one single most important thing behind the advancement of medicine is good science.

That’s why I really, really hate scientific fraud, and I’m really, really upset, perhaps even more so than Dr. Atwood, over the discovery last week of what is arguably one of the most massive scientific frauds in medical history. It doesn’t matter that Dr. Atwood is an anaesthesiologist and I am not, meaning that the specific scientific fraud unearthed, which was perpetrated by an anesthesiologist studying multimodal anesthesia, as reported in Anesthesiology News, the Wall Street Journal, and the New York Times. I am a surgeon, and the relief of surgical pain in my patients is an important part of my practice. If the scientific basis of what my colleagues in anesthesiology do before, during, and after my operations is called into doubt, I have to wonder if I am giving my patients the best surgical care. Aside from that, there is the intellectual outrage I feel as a result of seeing science and patients betrayed in such a systematic and blatant manner.
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Posted in: Clinical Trials, Health Fraud, Pharmaceuticals, Science and Medicine, Surgical Procedures

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Another challenge to surgical dogma

Better late than never with this one.

The dogma that I’m referring to is the remaining practice of using NG tubes in anyone with upper gastrointestinal surgery (liver, stomach, pancreas, duodenum, proximal small intestine) and then placing a jejunostomy tube (a tube, also often called a J-tube, that goes into the jejunum, or the proximal part of the small intestine, through which feedings can be given). The rationale for this was that the peristalsis of the small bowel returns almost immediately; it’s the large bowel and stomach whose return of peristalsis is delayed. Consequently, liquid tube feedings, it was thought, could be given beyond the point of surgery into the small bowel because if there is one surgical dogma that the evidence generally supports and probably always will, it’s always better to use the gut for nutrition than to use total parenteral nutrition (TPN, or feeding by veins). Moreover, there was evidence that such feedings had a protective effect on the lining of the bowel, preventing a phenomenon known as bacterial translocation, in which bacteria could pass through the compromised lining of the bowel after surgical stress. The price, however, was the placement of a tube into the proximal intestine, a procedure that, while safe, was definitely not without complications, some of which (such as bowel perforation) could be serious and require reoperation.

Challenging this dogma is the largest multicenter randomized study yet looking at this question: Which is better, bowel rest (NPO) and J-tube feedings or just letting the patient eat the next day? The study comes out of Norway1 and involved 453 patients. Blinding, much less double blinding, was, as is the case in many surgical trials, not possible because of the very nature of the question being examined, but other than that the design of the study was about as strong as a surgeon could ask for. Basically, patients were randomized to a routine of NPO and J-tube feeding until flatus indicated return of bowel function versus normal food at will beginning on postoperative day one; the experimental design is summarized below:
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Posted in: Clinical Trials, Science and Medicine, Surgical Procedures

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South Dakota’s Abortion Script: The Hijacking of Informed Consent

In a previous post, I suggested that informed consent could sometimes be misused. South Dakota has provided a clear example of such misuse and has set a frightening precedent reminiscent of Big Brother in George Orwell’s 1984.

A law went into effect in July, 2008, requiring that any woman seeking an abortion in South Dakota must be told that she is terminating the life of “a whole, separate, unique, living human being” with whom she has an “existing relationship” and that abortion terminates “her existing constitutional rights with regards to that relationship.”

It requires that doctors give patients information about medical risks, but it doesn’t leave anything to chance: it specifies what the risks are, including depression, suicide, danger to subsequent pregnancies, and death. The current state of development of the fetus must be described, and the woman must be asked if she wants to see a sonogram of the fetus. All of this must be done in writing, and the woman must sign each page of documentation. Physicians who fail to comply can lose their license or be charged with a misdemeanor. (more…)

Posted in: Politics and Regulation, Surgical Procedures

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Fecal Transplants: Getting To The Bottom Of The Matter

Many Americans will be introducing more food than usual to their GI tracts on this Thanksgiving Day, and so I thought I’d provide you with a special gastroenterology-related post to complement the mood. If you have already eaten, I might suggest that you come back to this post on an empty stomach. I will be discussing the alternative medicine practice known as “fecal transplantation” and it is rather unsavory.

The idea of transferring stool from one person to another (for the treatment of various GI disorders) was first described in the 1950s. This month the TV show, Grey’s Anatomy, featured the practice in one of their plot lines – which rekindled interest in the therapy, and resulted in an explosion of search engine activity. I figured it was probably my duty, as a member of Science Based Medicine, to offer a rational analysis of the treatment in the hope that the Google gods will serve up my post to a few of the information-seekers out there. I hope to reach them before the snake oil salesmen, wrapped in their mantle of “gentle, natural cures,” convince them that they desperately need a good colon or liver cleanse, if not a fecal transplant.

Like most alternative therapies, fecal transplantation is based on a drop of truth and a gallon of pseudoscience. It is true that the gastrointestinal tract is teeming with hundreds of thousands of bacterial species and pseudo-species, and that without them we would die. It is also true that certain nasty bugs (like clostridium difficile) cause problems when they take up residence within the gut. Antibiotics do upset intestinal flora, much to the consternation of infectious disease specialists. Now, all that being said – the practice of repopulating the gut with another person’s stool requires some fairly grand assumptions about efficacy and safety that are not founded upon any clinical trial data whatsoever.
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Posted in: Surgical Procedures

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Circumcision: What Does Science Say?

Some people think circumcision is mutilation; others want one even if they don’t know what it is. When I was working in an Air Force hospital emergency room one night, a young airman came in requesting a circumcision. I asked him why he wanted one. He said a couple of his friends had had it done, and he’d heard it was a good idea, and he was going to be getting out of the Air Force pretty soon and wanted to have it done while Uncle Sam would still foot the bill. I examined him: he had a neatly circumcised penis without so much as a hint of any foreskin remnant. I’ve always wondered what he thought we were going to cut off.

The subject of circumcision evokes strong emotions. Some people think of neonatal circumcision as a religious duty or a valuable preventive health measure; others think it is the epitome of child abuse. I have no strong feelings either way. I’m not sure what I would have decided if I’d had sons; fortunately my children were both daughters so I didn’t have to decide. I’m going to try to stand back and look at the scientific evidence objectively. What are the medical benefits and risks of circumcision? (more…)

Posted in: Medical Ethics, Surgical Procedures

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The Orange Man

The first thing that struck me about him was that he was orange.

It was not a shade of orange I had ever ever encountered before in a patient. It was a yellowish orange, an almost artificial-looking color. At first I wondered if he was suffering from liver failure with jaundice, but this orange was just not the right shade of yellow for jaundice, and his sclerae were not yellow. I also considered whether he was suffering from renal failure, but the orange color of his skin didn’t quite match the rather coppery color that some patients suffering from longstanding renal failure necessitating dialysis sometimes acquire. I was puzzled. His chart said that he was being admitted for surgery for rectal cancer. So I sent the intern in to get the story, do the history and physical, and get him all plugged in for his bowel prep. Believe it or not, there was actually a time when it was not all that uncommon for patients to come into the hospital the night before major abdominal surgery in order to undergo a preoperative bowel prep, rather than being forced by their insurance companies to undergo the torture of drinking four liters of the purgative known as Go-Lytely–a misnomer, if ever there was one!–at home and spending the next several hours having to rush periodically to the toilet, waiting in vain for the liquid exploding out of their hind end to run clear.
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Posted in: Cancer, Clinical Trials, Science and Medicine, Surgical Procedures

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The media versus the frontiers of medicine and surgery

A couple of months ago, one of my esteemed co-bloggers, Wally Sampson, wrote an excellent article about borderlines in research in conventional medicine. Such borderlines are particularly common in my area of expertise (cancer, which is also Dr. Sampson’s area of expertise) because there are so many cancers for which we do not as yet have reliably curative therapies. Patients faced with unresectable pancreatic cancer (as, for example, Patrick Swayze and the President of the American Medical Association have been diagnosed with) or metastatic solid cancers against which medicine generally has mostly palliative treatments, it is very tempting to take a “what have we got to lose?” attitude and pursue increasingly aggressive therapies that may actually shorten what little life a patient has left, all too often making that little bit of life more miserable than it had to be. As Dr. Sampson described in great detail, this sort of push to the borderlines and beyond led to the widespread acceptance during the 1990s of bone marrow transplantation as a treatment for advanced or inflammatory breast cancer based on uncontrolled studies that suggested a benefit. Later studies demonstrated no survival benefit (and possibly even a detriment), and that, or so it would seem, was that.

Except it wasn’t. Indeed, the other point that Dr. Sampson made was how the press covers these sorts of issues. He discussed a story that appeared in the San Francisco Chronicle about a young woman with advanced breast cancer who underwent stem cell transplantation for stage IV breast cancer at M.D. Anderson Cancer Center and was embroiled in a fight with Kaiser Permanente, her insurer, which refused to cover the treatment because it was deemed experimental and was at the time covering the cost of radiation therapy but refusing to cover the costs of extra followup scans required by the M.D. Anderson protocol. The article, not surprisingly, covered the story from the angle of the brave young cancer victim being further victimized by a greedy insurance company. And Evanthia Pappas is no doubt brave, and no one could read about her plight without rooting for her to beat the odds. The problem is that no consideration was given to just how unlikely this incredibly expensive treatment was to benefit her and whether it was even ethical to be doing such a study in which the patient bore over $200,000 of the cost for a treatment that was indeed experimental and being studied in an uncontrolled clinical trial. There are some very thorny medical, ethical, and financial issues there indeed.

Perhaps the reason Dr. Sampson’s post resonated with me was because it reminded me of a story that was extensively discussed last year, so much so that I saved the link to it. The story (Cancer Patients, Lost in a Maze of Uneven Care) appeared on the front page of the New York Times last summer. The article in question starts out by telling a truly sad story about a 35 year-old woman who, after giving birth, was diagnosed with Stage IV colon cancer as the human interest “hook” with which to represent what is described as a systemic problem with cancer care in this country:
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Posted in: Cancer, Medical Ethics, Science and Medicine, Science and the Media, Surgical Procedures

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