Monday, February 28, 2011

Honor Thy Gut (Marin IJ)

The human intestines (the gut) are like something out of a sci-fi movie, a world inside a world with much more intrigue than you might expect. Your gut, comprised of two dozen or so feet of twisting peristaltic tubes, has a mind of its own – looping, gurgling and diffusing its way to digestion. Slow and steady like a caterpillar on the move, the bowel functions in anonymity, until something goes wrong.

Deep in the bowel you’ll find a stew of microorganisms that make the breakdown of food and absorption of nutrients possible. Scientists know this crock-pot of little critters as a mircrobiome and it consists of millions of densely packed bacteria and yeasts, with names like Lactobacillus, Bifidobacterium, and Saccaromyces. In sum, these body microbes outnumber human cells by ten to one! Constantly at work, the gut microbiome serves many crucial functions; it turns food products into usable energy forms such as sugars and short chain fatty acids, it produces vitamins such as Vitamin K and biotin, and it protects against disease in a number of ways. And while we’ve known for some time that microbes play a critical role in the gastrointestinal tract, we are just beginning to appreciate the magnitude of their influence and the uniqueness of their composition on a person-to-person basis. That’s right, your microbiome is unique to you – it’s your own living micro-signature.

So, you may be wondering what you can do to cultivate a healthy microbiome? Recently, I spoke with Lita Proctor, Ph. D, Coordinator of the Human Microbiome Project – a National Institutes of Health (NIH) funded endeavor to catalogue the microbe communities of the human body using sophisticated DNA analysis. The following tidbits of advice are based on her thoughts as well as a sampling of the available scientific evidence.

*You and your microbes will have many more good times than bad. For every microbe-induced sore throat or upset tummy, there will be thousands upon thousands of illnesses that your personalized microbes will shield you from.

*Pro-biotics (live microbes found in products such as Culturelle and Align) do work – some of the time, for some conditions. But we don’t know exactly why. Someday, your medical record may include a full tracing of your genome and microbiome – allowing us to predict and prevent common nuisances (such as antibiotic-associated diarrhea). But until then, consider pro-biotics in certain situations (such when you’re dealing with antibiotic-associated diarrhea) but do so with some caution. Newborns (who begin sterile but start to assemble their own microbiome as they pass through the birth canal) and people with compromised immune function probably should not routinely be supplemented with excess microbes. For more information on pro-biotics, check out the National Center for Complimentary and Alternative Medicine at http://nccam.nih.gov/health/probiotics/

*Pay attention to pre-biotics. No, that’s not a typo. Pre-biotics as the name suggests, are like the precursors of pro-biotics. These nondigestable food ingredients, called oligosaccharides, stimulate the growth and activity of the gut microbiome. They are found in many vegetables as well as in bananas, oats and soybeans. In a recent Italian study, adding pre-biotics to re-hydration fluid for children with diarrhea significantly reduced the severity and duration of symptoms (compared to standard re-hydration fluids). The NIH is actively investigating both pro-biotics and pre-biotics, in fact they have assembled a working group tasked with identifying “gaps and challenges in pre-biotic and pro-biotic research.”

*Keep your calories down. One proposed explanation for our obesity epidemic is that obese people have, over time, preferentially selected (via natural selection, not conscious selection) certain highly efficient gut bacteria. These bacteria are much better at extracting energy from food than the gut bacteria of thin people. The theory is that once you’ve cultivated these super efficient microbes in your GI tract, you’ll extract more calories from your food even when you eat significantly less of it. Perhaps someday there will be an antibiotic for obesity, but in the meantime, best not to overeat. By the way, another in-vogue hypothesis is that a nutrionally-balanced low calorie diet can extend your life span. Animal studies and some preliminary cardiovascular-based studies seem to support this contention. So, live little rather than go big and you might just stick around longer.

*When it comes to cleansing, moderation is key. Don’t go crazy de-toxing, bleaching, and germaphobing. Gut cleansers and unnecessary antibiotic users – this means you. Heard this before? Well’s it’s called the hygiene hypothesis; the contention that modern society, like the town pastor in Footloose, protects us too forcefully from the unclean, depriving our immune system from useful practice and our microbiome from helpful stimulation. So, when you are sick or in the hospital, be sure to strictly follow hygiene standards, but otherwise remember, “Gaia made dirt, and dirt don’t hurt.”

Of course infectious diseases are still major killers and interventions like vaccinations and antibiotics undoubtedly save millions of lives. But let’s take time to celebrate the good little guys, too. Let’s thank the microbes that ferment grapes and hops, produce yogurt and cheese, and raise lofty loaves of bread. And let’s be proud of our personalized squadrons of sustenance-processing magicians and give them a helping hand every once in a while. If you find yourself in a digestive rut, go ahead and cultivate that gut!

Saturday, February 12, 2011

Stroke of Genius? (Marin IJ)

If your normally stoic mother were to call and say, “Honey dear, I seem to have a bit of a conundrum. I’ve suddenly developed numbness and weakness on the entire left side of my body.” How would you respond? If you’d call 911, then -- ding-ding-ding -- you are on the money. Sudden weakness on one side of the body is highly suggestive of a stroke or transient ischemic attack (TIA). In this situation, your mom needs to be seen as quickly as possible in an Emergency Department (ED). But does it matter what type of hospital she is seen at? Well, this is a matter of debate, but evidence now suggests that, yes, it could matter.

Over the past decade, spurred by recommendations from the American Stroke Association and the affiliated Brain Attack Coalition, hundreds of hospitals across the country (more than 700 actually) have received certification as “primary stroke centers.” The rationale for this paradigm shift in stroke care is primarily based on two observations. One: despite improved preventive care, stroke remains a leading cause of death and the leading cause of disability in this country. Two: much like with a heart attack where the saying goes “time is myocardium,” there are clock-dependant treatments for acute stroke too. You might say, “time is brain”. And while the leading emergent stroke treatment (an intravenous blood thinning medication called t-PA) has been a topic of significant debate, its use in patients with ischemic stroke (stroke caused by clot or decreased blood flow rather than by bleeding in the brain) within 3-4 hours of symptom onset is now largely accepted as the standard of care.

So, hence a certification process to improve, integrate and standardize care – spanning from the pre-hospital setting (ambulance response) to after hospital discharge. This process, primarily administered by the non-profit hospital accreditation body known as The Joint Commission, is rigorous, multidimensional and requires annual or biannual site visits. I won’t bore you with excessive details, but if you are interested, you can visit The Joint Commission’s website at http://www.jointcommission.org. Here in Marin County, we have two certified primary stroke centers, Kaiser San Rafael (certified in 2008) and Marin General Hospital (certified in 2010). Novato Community Hospital is affiliated with a stroke center (California Pacific Medical Center) in San Francisco.

Despite the time and resource-intensive nature of stroke certification, up until recently there has been limited data to justify the effort – especially in the community hospital setting. However, that is starting to change. A study out of Finland of over 60,000 patients with ischemic stroke (published last year in the journal Stroke) found improved one-year mortality rates in those patients treated at hospitals meeting stroke center standards. Closer to home, a study of 358 stroke patients seen at San Rafael Kaiser between January 2007 and July 2009 found that after stroke certification there was a 15% increase in the percentage of patients arriving at the ED early (within 6 hours) after stroke symptom onset – although this did not equate to greater use of t-PA. These pieces of evidence, though, are rather soft and difficult to generalize to the U.S as a whole. That is why a recent investigation of New York hospitals, published last month in JAMA, may become a cornerstone study for the stroke center movement.

Dr. Ying Xian and colleagues compared 30-day death rates for over 30,000 patients admitted to hospitals with acute ischemic stroke between 2005 and 2006. The researchers discovered that those treated at a state-certified stroke center (with criteria similar to that used by The Joint Commission) had modestly better mortality rates (10.1% versus 12.5%) than those who were not. This mortality benefit persisted at one year past hospitalization. The researchers also found a nearly three-fold higher rate of t-PA use in stroke centers. Importantly, they did not find a mortality benefit when comparing the outcomes of patients with two other life-threatening conditions (heart attack and major gastrointestinal bleeding). This suggests that stroke centers (at least in New York) are not across-the-board better hospitals than non-stroke centers, but that they do provide better care for stroke patients. Thus, while other investigations are ongoing (including a comprehensive one within Kaiser Northern California) and it remains to be seen if the New York numbers are reproducible nationwide, this does appear to be a pretty convincing justification of the stroke center model.

So, let’s return to that call from your normally stoic mother with sudden numbness and weakness on left side of her body. Several years ago, a survey of Michigan adults used virtually the same language and asked respondents what they would do. A mere 42% stated they would call 911. Rates for calling 911 were also low for two other classic stroke presentations “Sudden trouble speaking or understanding what is being said,” (51.5%) and “Sudden trouble seeing in one or both eyes” (20%).

This study demonstrates that we have work to do in educating the public about the signs and symptoms of stroke. Keep in mind that there are many odd sensations that are not suggestive of stroke – generally feeling week, isolated tingling without weakness, and vision problems associated with pain. For these symptoms, be assured that the risk of stroke is low. But if you experience the symptoms mentioned above and/or sudden and severe headache, or non-alcohol related loss of coordination (more info at http://www.strokeassociation.org) -- it is time to give your local emergency medical services ( EMS ) a call. EMS response is the first step in the stroke center model of integrated care. And while the jury is still out in the assessment of stroke centers, everyone should know that timely medical evaluation for people with suspected stroke is beneficial.

To help remember, think ‘time is brain.” But that doesn’t exactly roll off the tongue does it? How about “act fast so that you don’t croak when you stroke,” or “if in doubt, give EMS a shout”? No matter your preference, I do hope you’ll take a moment to learn more about stroke.

Sunday, February 6, 2011

Weaning the Vent *Excerpt from Chapter 1*

“Assessment and plan,” declared Lesley, who was wrapping up her presentation to our small team of physicians. “Angelina Andriola is a previously healthy fourteen-year-old girl acutely ill with presumed sepsis of unknown origin with systemic inflammatory response syndrome. She is on day two of broad spectrum antibiotics – nafcillin, cefotaxime and flagyl. She is hemodynamically unstable… ” Lesley spoke with meticulous cadence, and I suspected that she was a meticulous physician – the type who arrived two hours before morning rounds and knew your patients even better than you did. Staring intently at her clipboard, oblivious to the imploring eyes from the corner of the room, she finished ,“…and is on an epinephrine drip to support blood pressure and on maximum ventilatory support with an oscillator ventilator. Since admission to the PICU, we have been unable to wean the vent.”

“Okay,” said our attending physician, Dr. Connor, in a baritone. “Here’s what we are going to do...” Dr. Connor – and as my superior I was expected to call refer to him formally as Doctor – was a bear of a man, stout through the chest and neck; not exactly the waifish, Mickey-mouse-tie-wearing pediatrician of my internal stereotype-oscope. He had a bushy goatee and the faint stubble of a receding hairline. I’d heard from other residents that Dr. Connor was an excellent clinician and tolerant teacher, who occasionally transformed into a volatile autocrat. “I want to turn Angelina over. Let’s get her off her stomach, flip her supine, and let’s see how she does. If she can’t maintain her oxygen sat above ninety, we’ll have to turn her back prone. And, let’s try and get a feeding tube down so that we can get her some nutrition. Now,” he said while rotating towards the girl’s parents, who were standing attentively nearby “Questions?”

“Yes, Doctor.” The girl’s mother started to speak but her father, a pale man with a grey speckled beard and intense red-rimmed eyes, interjected. I studied him for a moment and thought, oddly, of Richard Dreyfuss.

“Absolutely, I have questions,” he said. “You have to explain some of this in layman’s terms. What does ‘hem-o-dy-nam-ically unstable’ mean, and what about ‘su-pine’ and ‘prone’? What, exactly, does it mean that Angelina is on ‘maximum vent-il-atory support.’” His recitation of these medical terms was impressively and surprisingly accurate. He continued, “and that you are unable to ‘wean the vent’? Are you telling us that there isn’t anything more you can do? It seems to me that it is a complicated way of saying that there’s not much more that you can do for Angelina.” His reddened eyes began to glisten faintly. “You do realize, don’t you, that Angelina was perfectly healthy before she arrived at this hospital?”

Dr. Connor paused, as if stifling a sigh, before replying. “Mr. Andriola, we haven’t run out of options for treatment, but your daughter is extremely sick and requires the very highest level of support for her hemodynamics – her heart rate and blood pressure – and from the ventilator. Her oxygen saturation…her blood oxygen level, is very tenuous. So far, we haven’t been unable to wean, that is reduce, that support. But we will keep trying. So far, your daughter has done much better on her stomach, in the prone position, than on her back.” He pivoted towards Lesley, “Doctor Gallagher, could you spend some time with Angelina’s parents this morning? Okay, who’s next?”

And with that, our small pack of physicians – Dr. Connor, myself, and three other residents moved out of the room. I looked back as we left and saw Mr. Andriola, mouth twisted open. In front of him lay his daughter, Angelina, no more vibrant than a lump of coal. I watched as the girl’s mother stepped forward and gently kissed her daughter on the head.