Medicine Changes

Back in 2008, as a third year medical student, I did a small review of research articles on the topic of CT scans to screen for lung cancer. I've talked about screening extensively in the past, but the idea is to run a test (mammogram, PSA, Pap smear, etc.) on an asymptomatic patient to detect cancer before it causes signs and symptoms. This sounds great until you look at statistics on a population level. If a test is not perfect - that is, if it gives false positives - then it can cause undue burden on that patient, lead to more invasive investigation, and result in adverse outcomes or side effects. Furthermore, even if the test is positive, researchers should prove that catching it earlier benefits patients. This may seem strange, but it's not directly evident that catching a breast cancer a year earlier because of a mammogram done before the lump is felt translates directly into more lives saved.

The problem with lung cancer is that when it becomes symptomatic - coughing blood, difficulty breathing, metastases - it is often too late. This is the kind of disease where screening makes sense. But chest X-rays did not pan out; they aren't sensitive or specific enough - that is, they don't catch many masses and the masses they do catch might not be lung cancer. So CT scans were proposed. When I did the literature search in 2008, I concluded that there was no good evidence that CT scans on asymptomatic smokers would save lives by catching lung cancer earlier. Furthermore, because CT scans are costly, involve radiation, and still have false positives, I concluded that they should not be done for asymptomatic patients.

This is a long-winded introduction to a new guideline I recently read that the American Lung Association now recommends CT scans to screen for cancer in smokers with a 30+ pack year history age 55-74. This fascinates me. In the four years that have lapsed, have our scans become better? Are our radiologists better? Or has there been a new landmark trial? Or are they looking at the data I examined and coming up with a different conclusion?

In the end, this reminds me that medicine changes rapidly. I won't buy the guideline until I examine the literature again - at which time I may be swayed or not. But what we learn, even if it was state-of-the-art up-to-date cutting-edge knowledge a couple years ago, may become old news really quickly. Like technology (the first iPhone was just 5 years ago), the landscape of medicine evolves incredibly rapidly.

Cardiopulmonary Bypass

The problem with operating on the heart is that it is very difficult to do surgery on a moving organ, especially when that organ is nonnegotiable and there is no margin for error. But to stop the heart would be fatal to the body without another means by carrying blood and oxygen to the organs and removing waste products from them. Furthermore, even if a surgeon could operate on the beating heart (which is done occasionally as "off-pump coronary artery bypass grafts"), if the surgery requires entering any of the heart's chambers, then the heart must be still.

Cardiopulmonary bypass changes everything. In the most simplistic description, a surgeon puts in a catheter into the aorta (occasionally the femoral artery) and into the vena cava or right atrium (occasionally the femoral vein). The blood is thinned with heparin to prevent clotting as it leaves the body. Blood is withdrawn from the vena cava or right atrium before it can enter the heart. It goes to the machine where it is oxygenated, filtered, and warmed or cooled. Then it returns to the body into the aorta where it perfuses the organs. In this way, the heart and lungs are completely bypassed, giving the surgeon a bloodless field in which to work.

What impresses me is that the first successful case of this occurred in 1953. Although technology has certainly improved since then, there are still a lot of risks and complications associated with cardiopulmonary bypass. A lot of trauma occurs to the blood components and there is a high risk of bleeding afterwards. The body mounts an inflammatory response leading to leaky vessels, changes in mentation, difficulty maintaining a blood pressure. As a result, we try to limit time on the pump to reduce the effects of cardiopulmonary bypass.

Image of cardiopulmonary bypass is in the public domain, from Wikipedia.

The Transplant

We cover heart and lung transplants on the cardiac anesthesia service, and I've seen one of each. It is amazing. The surgeons are called when an organ donor may have a viable heart or lungs. They go to procure the organ while I quickly meet the patient, who has often driven in from far away or waited patiently in the coronary care unit. The room is set up for a typical bypass case, and indeed, surprising as it may seem, a heart transplant is not as complicated as some of the other surgeries we do.

There is a simultaneous process where the organ is prepared as the patient is anesthetized and the chest opened. The patient is placed on bypass, the old heart stopped, the body receiving sustenance from the heart-lung machine. The new organ looks pristine. The heart is beautiful, a perfect anatomic specimen, its thin arteries and veins tracing outlines over the pearly surface. And in a process that can almost be simplified into disconnecting an old CPU from all its cables and reconnecting them to a new one, the heart is implanted. At first, it stretches, trying to feel its new surroundings, groggy and waking from its stunned silence. And then it begins to beat with vigor, and the body breathes a sigh of relief.

The lungs are similar, waking up with slow breaths, inflating with gentle pressure. There is a challenge to coaxing the lung back to work, prodding it without damaging it, giving it oxygen without toxicity (the oxygen can be damaging to the new organ). Ultimately, however, it is the course afterwards that is difficult, treading the fine line between acceptance and rejection of the new organ.

Image of a transplanted heart shown under Creative Commons Attribution Share-Alike License, from Wikipedia.

1500

This is the 1500th post! Looking back, it's hard to imagine that when I first started this blog, I had never seen an operating room, didn't know the meaning of the word anemia, couldn't place an IV. And now, six years into this medical world, it feels easy. I'm pretty sure this blog won't last forever, but for now, I'll keep it going. Thanks for following.

Image is from my friend Julia.

Valve Replacements

On cardiac anesthesia, I commonly see aortic valve replacements for aortic stenosis. Aortic stenosis, narrowing of the gateway from the heart to the rest of the body, causes symptoms by limiting the heart's ability to pump blood adequately forward (like a clogged pipe). Repair or replacement of the valve can relieve the strain on the heart, eliminate symptoms, and extend the patient's life.

However, some valve disorders like aortic stenosis (as well as mitral regurgitation) have great anesthetic implications. So part of the challenge and learning in these cases is to anesthetize these patients without compromising the heart. The heart is often working as hard as it can for these patients, and there may be concurrent coronary disease as well. Anesthetics drop the blood pressure, and this can be catastrophic to the unprepared anesthesiologist.

Some of the surgeries I've seen are even more complicated like double valve replacements for aortic stenosis and mitral stenosis (a much rarer disease and difficult to approach surgically) and Partner trial cases, a clinical trial for surgical treatment of aortic stenosis. It's very educational seeing the range of simpler straightforward cases to the harder tertiary-care ones.

Prosthetic heart valves shown under GNU Free Documentation License, from Wikipedia.

Suturing

The thing about being an anesthesiologist is that I watch surgeons suturing and closing incisions every single day. Yet when I have to put a stitch into an arterial or central line, I am embarrassingly slow. This is how I knew I belonged on this side of the drapes. But I ought to remember this next time I watch new residents placing stitches, and maybe I should take some suture home to practice.

Image shown under Creative Commons Attribution Share-Alike License, from Wikipedia.

Who Pays For It?

Here is a hypothetical scenario. An older gentleman is scheduled for a total knee replacement. On the pre-operative anesthesia exam, his airway looks reasonable. He's brought into the operating room and anesthesia is induced. However, the anesthesiologist cannot intubate the patient; he has an unanticipated difficult airway. He calls for the difficult airway cart, puts in a laryngeal mask airway as a rescue, uses a fiberoptic bronchoscope, and safely intubates the patient. The surgery gets underway. The surgeon, examining the patient and the X-rays, asks for one prosthesis. However, as he starts putting this prosthesis into place, he realizes it doesn't fit perfectly. He then asks for a different prosthesis. The rest of the surgery finishes uneventfully.

This could be a fairly common situation happening throughout the United States. Despite our best efforts from an anesthesia and surgical side, we run into unanticipated problems requiring new and different equipment. But who should be charged for this equipment? Should the patient be billed for the resources going into the initial intubation attempt as well as the rescue? Should he be billed for one or two prostheses? In both cases, it's not his fault that additional resources were required; in fact, given that the surgeon and anesthesiologist did due diligence, it's no one's fault. So then does the hospital absorb these costs?

Or consider a teaching facility. A patient could be intubated simply and easily with direct laryngoscopy. But the attending wants to teach the resident to use a video laryngoscope, and he is intubated with that. Should he be billed for the higher-cost more-complex procedure even though this was done only for educational purposes? A surgery resident is closing up an incision, but because he is less efficient than the attending, he uses an additional pack of sutures. Who accounts for that?

I don't know the answer to these questions, though I have a suspicion that the hospital picks up the excess. However, I also don't know what the right answer is and although I don't think this is a large contributor to the cost of healthcare in America, it certainly has some effect.

Home Call

One of the quirks of this rotation is "home call." We take call on average every fourth night, and on our call days we are usually scheduled for the longest case of the day - most commonly multiple valve replacement, aortic arch repair, or correction of congenital heart disease. After we finish our case, we finish up any remaining cardiovascular surgeries or add-ons. But once all the rooms are finished, we can go home, provided that we can get back to the hospital within 30 minutes. We are available for emergent take-backs, aortic dissections, heart transplants, embolectomy, and other life- (or limb-) threatening cardiovascular issues. When we take call on the weekends, it's a similar situation if there are no elective cases booked.

Home call is an odd concept. It is absolutely wonderful to be able to go home and sleep in my own bed, but the sleep is fraught with stress. I always worry about what might come in and my response time. I don't sleep as soundly. I check my pager obsessively. But as it counts as a real call and we get the following day off, I cannot complain.

Vascular Surgeries

The most common vascular surgeries are those done on the carotid artery and the abdominal aorta, and I got to provide anesthesia for these surgeries on my first day on cardiac. In the same way that cholesterol can build up in coronary arteries for the heart, plaques develop in the arteries of the neck supplying the brain and in the aorta. The image above shows one of these carotid plaques at the bifurcation of the vessels going up to the head. As you can imagine, these can easily cause a stroke.

The anesthesia for these procedures can be delicate. Patients who have plaques like this are likely to have them on the heart; they are unfortunately the smokers with high blood pressure, poor cholesterol, diabetes, and obesity. So these procedures have a higher-than-normal risk of heart attack and stroke. We have to use a gentle induction of anesthesia to maintain a good blood pressure through the surgery (some people even do these surgeries awake with local anesthetics, but this is a lot less common these days). We use fancy monitoring of the brain that can detect gross changes in cerebral oxygenation; this can clue us in on a stroke early on.

The same thing applies to those with disease of the abdominal aorta. Aneurysms of the aorta develop in areas of wall weakness from cardiovascular disease. Some of these patients are too sick to have the aneurysms repaired in an open fashion, but now we can fix them intravascularly with stents deployed from the groin. However, as I provide anesthesia for these patients, I am reminded that we have to be aware of all the organs; the lungs of these smokers are often poor, their obesity makes the airway challenging, they have presumed heart disease and often have poor exercise tolerance. Although these procedures are common, we cannot be cavalier with them.

Image of carotid artery plaque shown under Creative Commons Attribution License, from Wikipedia.

Cardiac Anesthesia

I started my two-month block of cardiac anesthesia. We focus on open-heart surgeries such as coronary artery bypass grafts, valve repairs and replacements, and aortic surgeries. We also cover vascular cases like carotid artery and abdominal aortic surgery as well as procedures in the cardiac catheterization lab. The open-heart cases are big surgeries that often take all day and utilize cardiopulmonary bypass. From an anesthesia standpoint, I have to arrive quite early in the morning because the set-up is fairly intricate. After starting an IV and an arterial line, I generally induce anesthesia, intubate the patient, get additional access, and place a large catheter in the neck as well as a multi-lumen catheter to give vasoactive drugs. We place a transesophageal echocardiography probe to take a look at the heart, and it's very helpful that I did my echo rotation last month.

In cardiac surgery more than anything else, the anesthesia is tied to the surgery so that what the surgeons do to the heart reflects what I see on the monitors and what I do with my ventilator affects the surgery. Furthermore, nearly all heart pathology is pertinent to anesthesia; if we don't understand the patient's coronary blood supply and valve status, we can cause a lot of harm on anesthetic induction. We also have to interact with a third provider, the perfusionist who is in charge of cardiopulmonary bypass. Thus, this is an important rotation to learn about anticoagulation and reversal as well as massive transfusions because bleeding is often prominent. We have to learn how to control hemodynamics when the surgeons cannulate the great vessels to set up bypass and how to check that everything is positioned well and working by echo.

It will be a good rotation but a tiring one. I am confident that by the end, I'll be much more comfortable with advanced heart disease, placing intravascular lines, and managing coagulopathy.

Poem: Pele

Sorry for the slow blogs. I spent the last two days writing a poem, but it's been so long that I feel rusty. In any case, I have lots of friends whose blogs have gone extinct from blog fatigue, but I don't think that is the case here. I just have general fatigue, but I will keep writing as I can as there's a lot of interesting things on my mind.

-
Pele

This is anger: hair and tears pummeled into the air,
a fine mist of sear, a scatter of curses, beautiful
beyond belief, now caged behind glass,
and you can almost hear her fury
echo within that chamber, the same screams
magnified a thousand times within the throne
of the goddess herself. Pele, eyes aflame, livid
with passion whose tantrums bring prostration,
whose taunts rend canyons into stone.

How base, how excessive, how gorgeous
her demands engulf tree after tree.
A plume of light takes flight, and then dies.
I stand on years-old inclement, fury that has
cooled into memory, then rotted to stone
as younger, newer angers make themselves known.

I heard of a thief who ran with the gravel
of unrequited love, who thought he could allay
her emotion, satisfy her lust. It was a small thing,
hollowed where air burrowed its way out,
the way an insect might escape. He returned
the stone years later, then never left her mantle.

Paradoxes in Medical Economics

When a patient with insurance is billed for a service, their insurance company negotiates lower prices for that service. When a patient without insurance is billed for a service, he has no negotiating power and so he ends up being billed for much more. And yet it is the patient without insurance who has the greater financial burden and who most likely cannot afford the higher price. Everyone argues that the uninsured patient does not pay bills anyway, but I have met many patients and families who struggle to put together money to cover their bills. These are the patients who we should be lowering our prices for; even if financial assistance is available, it makes so much more sense to me to discount things up front. Medical economics is a black box to me, and sometimes things don't make any sense.

Cardioversion

Cardioversion is a procedure where a heart in an abnormal rhythm is shocked to reset its electrical impulses, hopefully to a normal rhythm. It is, in essence, rebooting the heart. In emergency code situations when a patient's blood pressure is critically low due to an abnormal rhythm, it can be life-saving, but we also do cardioversions electively in someone whose heart rhythm gives them symptoms or limits their activity but cannot be converted with medications alone. As shocking the heart is quite painful, anesthesiology is involved for these quick cases.

I do a quick history and examination of the patient and the EKG. The cardiologist sets up the defibrillator and I set up my mask, draw up some drugs, and check the IV. When everyone's ready, I give a quick bolus of propofol. Once the patient is unresponsive, I start mask-ventilating until the shock. After the shock, we examine the EKG and confirm sinus rhythm. The patient wakes up minutes later without any recall of the event.

I occasionally wonder, with such quick procedures, how necessary it is to have anesthesiologists (and in this case, a resident and a cardiac anesthesia attending), but I've realized we're there for when things go wrong. When everything goes smoothly, the cardioversion can probably be done with a cardiologist directing a nurse. But if the patient aspirates, vomits, has respiratory compromise, goes into an unanticipated heart rhythm, or has any other event, I am prepared to put in a breathing tube, support the blood pressure, and initiate advanced cardiopulmonary resuscitation. Furthermore, recent public events like Michael Jackson's death highlight the serious nature of propofol administration, a drug that anesthesiologists are most familiar and comfortable with as we use it every day.

VATS

VATS, an acronym that sounds strange to patients, stands for video-assisted thoracic surgery. Similar to laparoscopic surgery of the abdomen, the surgeon makes small incisions in the side of the chest to access the lungs. A 60 year old long-time smoker presents with a lung mass requiring a biopsy. The surgeon's plan is to use a camera and tools to go in through small VATS incisions and take a piece of the mass to find out if it is cancer or something else. This sounds easy enough, but the anesthesia is not straightforward. Can we stop the patient's breathing to allow the surgeons to work on a stationary field? The answer is clever: we isolate the patient's two lungs. The breathing tube we place is specially designed with two lumens and two balloons. Using a fiberoptic bronchoscope, we position it in order allow selective inflation and deflation of the two lungs. This type of intubation has its risks as well; we have to be vigilant for signs of tube movement as that can cause lots of problems. We also have to be able to oxygenate and ventilate the patient with just one lung while the surgeon works on the other one. All of these challenges makes thoracic anesthesia an interesting and satisfying field.

Unnecessary Surgery

In discussions about the cost of health care, health care reform, and doing the right thing for patients, we often bring up "unnecessary surgeries and interventions." Some people, including me, feel that we occasionally do too much, that we send too many tests, do too many things to people, and ultimately hurt them and or society. But I'm not writing about that today. After being on call this weekend, I have realized that another group of unnecessary surgeries stem from things that should not have happened. A teenager comes in after being stabbed multiple times. A motorcycle crash leaves someone blind. A person with depression tries to hang himself. For many of us, these are the patients we go into medicine to save. They have an acute injury and with intensive care, we can get them to walk out of the hospital. Those in emergency medicine and trauma find these situations immensely satisfying.

I can see that. However, there is a part of me that wishes these patients never came in in the first place. It is a public safety measure to decrease the amount of gang violence, motorcyclists without helmets, drivers without seatbelts. Each of these accidents dramatically changes that patient's life and costs the health care system an incredible amount. After surgery, these patients go to the intensive care unit and may stay in the hospital for days; even when they are discharged, they may have long-lasting effects of their injuries that lead to disability, chronic pain, and possibly poorer quality of life. Seeing this has helped me understand why public health includes such mundane issues such as traffic accidents, suicides, and weapons at home.

Debriefing

A woman in a car accident several days ago now has symptoms of a new stroke. The neurosurgeons would like to do intra-arterial tPA. Tissue plasminogen activator (tPA) is one of the miracle drugs of the last few decades. Most strokes are due to clots (the remainder are due to bleeds). tPA is a so-called "clot buster," and can reverse the devastating symptoms of a stroke if given early. There is a specific window of time in which it can be given, but if a patient is out of the window for IV tPA, then intra-arterial (IA) tPA may be considered. Furthermore, given this patient's recent history of a car accident, the risks and benefits of IV or IA tPA must be considered carefully because clot-busting can increase bleeding at other sites. After discussing these issues with the patient, the neurosurgeons decided to proceed with IA tPA.

The patient was brought into the room. She was 250 lbs and in a C-collar, which stabilizes the neck. Both of these concerned me because they make intubation much more difficult. I set up for a difficult airway with a fiberoptic laryngoscope and a fiberoptic bronchoscope. I induced the patient with general anesthesia and took a look with the fiberoptic laryngoscope. All I could see was epiglottis; it wasn't enough for me to identify vocal cords. At that moment, blood obscured my camera and I couldn't see anything. My attending took over but was unable to visualize things as well. When unable to intubate, we went to mask ventilation. However, the patient's body habitus prevented us from ventilating, even with an oral airway and a laryngeal mask airway. This was alarming. The incidence of "cannot-ventilate, cannot-intubate" patients is incredibly low, but when it happens, it means we cannot oxygenate the patient. This is even more important given that the patient was having a stroke. But after manipulation of the laryngeal mask airway, we were able to ventilate the patient, and her oxygen saturations came back up to normal. Finally, we used a fiberoptic bronchoscope and an exchange catheter to intubate the patient while ventilating them with the airway. In the end, we were able to place the endotracheal tube, but it was a harrowing experience.

I write about this not because of its severity, but because these situations require debriefing. They happen to every anesthesiologist and it is part of the consent I do when I speak to patients about the risks of anesthesia. But during the experience, I was terrified. Afterwards, I was shell-shocked. Fortunately, my attending did the rare thing and sat down with me after the case to discuss what happened, what we did right, and what we could have done better. It allowed me to express my worries and concerns and feel a lot better.

Gadgets

Stanford's anesthesia program is pretty cool because we have a few faculty members who are interested in technology and anesthesia. They've developed an iPhone app with all the critical phone numbers, call schedules, paging abilities, and even papers. We have a website, "Ether," which allows instant messaging (as well as paging), stores syllabi, streams podcasts and videos, and links to key university websites. It's all incredibly useful. One thing I've learned about medicine is that it is slow to adapt new technologies. There are lots of valid concerns (what if an iPhone with patient data is stolen?) as well as culture issues (if it isn't broken, why fix it?). As a result, a lot of things trouble me, like reliance on paper records, paging systems, calling an operator to get phone numbers. But luckily, the program here is shoring up these inefficiencies by creating practical websites and applications for everyday use.

Image of iPhone shown under Creative Commons Attribution Share-Alike License, from Wikipedia.

Repetition

As with learning anything, practice and repetition make a cornerstone of residency training. In between the excitement of challenging, strange, and unique cases, I am assigned to run-of-the-mill surgeries: PEG placement, sinus surgeries, dialysis graft placement. These aren't crazy enough to write blogs about, but they reinforce aspects of my training that need to become instinct. And slowly, I am becoming acculturated; I begin to anticipate alarms, become more efficient in setting up my room, and feel more comfortable with intubation.

It is something I say to patients often. Surgery is always a big deal to patients; there is no small procedure, and even a cataract repair is a big deal to the one receiving it. However, you want doctors who are comfortable enough to consider these straightforward, small interventions. We respect what we're doing, but we don't get all riled up. We've seen enough to know what's dangerous and how to prevent and treat it. Residency is the practice and repetition to achieve that.

The Patient-Doctor

Doctors usually don't make great patients. Whenever I have a patient or family member who is a physician, I find that the care is different than it would have been if they weren't in the medical profession. It's too hard to remain unbiased, and often unobjective physicians get side-tracked down one path or another. I spend my time explaining why excessive tests aren't appropriate or calling consults that are requested but ultimately unhelpful. I think patients get suboptimal care when they try to dictate it even though they mean otherwise.

So what happens when we get sick or our family members are injured? How do I, as a physician, navigate the healthcare system? It's so hard to remain completely passive, to try to be the ideal patient, unbiased, receptive, without interjecting our own thoughts, opinions, desires, and demands. How do I refrain from challenging the physician, asking for that extra MRI, or proposing an alternative treatment? We are all in the stage of lives when our parents, friends, and family members are hospitalized for things, big and small. They call us for support, but what's best for them? Should we come to their rescue, UpToDate in hand, an advocate who comes across as argumentative? Should we back away and act as the family and friend, providing emotional support, helping the patient, but not interfering with medical care? Are unbiased, objective providers better than we who care so fervently about ourselves and our loved ones, who have access to medical repositories, who have personalities that want to fix everything? I try my best not to step on other doctor's toes, especially in fields in which I have no expertise, but I know I probably make nudging comments because of who I am and what I know.

Book Review: Interpreter of Maladies

I also recently read Interpreter of Maladies, a collection of short stories by Jhumpa Lahiri. This Pulitzer Prize winning collection has nine fabulous stories about the Indian and Indian American experience. The stories capture a certain quality, poignancy, and magic about relationships coming together and relationships falling apart. My favorite piece, "A Temporary Matter," caught my breath with the beauty of its sentences and the simplicity of the situation - two people talking in the dark. Lahiri's writing is light, graceful, and musical. She caresses each word and sentence, understanding and exploiting the details - sounds, words, phrases. Although I found the overall collection to be a little heavy for me on immigrant issues, I also know that there is little Indian American literature and this provides a breath of fresh air, flooding us with numerous facets of a world to which we have little exposure. She avoids stereotypes and creates meaty, curious characters in engaging situations.

Image shown under Fair Use, from Wikipedia.