Wednesday, October 29, 2014

Ebola III - The 2014 Outbreak

The 2014 outbreak in West Africa is the largest Ebola outbreak and the first one in West Africa. It is concentrated in Guinea, Sierra Leone, and Liberia, though there have been cases elsewhere including some in Europe and the United States. It has been going on for many months but only recently started getting media attention. Many infectious disease, public health, and other experts suggest that this is a critical point in the spread of the outbreak; without adequate resources to contain Ebola, it may become a worldwide epidemic or pandemic.

Understanding the disease requires understanding the culture, history, and people of West Africa. I know little about this, but it is really important. The behavior of the disease depends intimately on the sociocultural context where it exists. For example, burial customs in West Africa often involve touching, kissing, or bathing the deceased. Much of the early spread of Ebola happened at funerals with the death of an infected person. Furthermore, ongoing risk and spread occur when family members or patients lie about their disease or symptoms because they worry they will not get a funeral. Without proper education, the virus will continue to spread even as it kills its host. But this simple point - education - is a challenge if the people of West Africa don't believe authorities.

Suspicion of medical personnel and facilities also contributes to the problem. There have been instances of health care workers and hospitals being attacked because of a scared public that doesn't understand Ebola. The delivery of health care is impeded if patients refuse to seek care when they have symptoms. These countries are poor; they can't even handle those who do present for care. Fear of the disease may limit the treatment rendered; many patients are underresuscitated because of a fear to place an IV. Lack of protective health equipment for providers means that many providers have contracted and succumbed to the disease. There are so many barriers preventing effective control of this outbreak. In order to successfully contain the disease, we need to address not just the medical aspect, but also the social milieu in which it resides.

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

Tuesday, October 28, 2014

Ebola II - The Scare

Unlike other recent "epidemic" scares like avian flu and H1N1, Ebola is not spread by respiratory or airborne mechanisms. It is spread by contact with bodily fluids such as blood, vomit, and diarrhea. This tells us who will be at highest risk: healthcare workers. I don't suspect that the general public will be at great danger for getting Ebola, but practitioners doing invasive procedures or caring directly for sick patients will be vulnerable. In the study of epidemics, a variable called R0 describes how infective a disease is; that is, how many people each infected person is likely to further infect. Compared with other diseases like measles, Ebola's estimated R0 is quite low, somewhere between 1.5 and 2. We have to decrease this below 1 to ensure a disease will be eradicated.

Lastly, Ebola is scary for many reasons. Its current case-fatality rate (what I think of as mortality rate) is estimated somewhere between 60-90% meaning the vast majority of patients who got it have died. But this is in the context of a developing country with limited physicians and resources trying to deal with a disease that's incompletely characterized. I imagine that the case-fatality in a developed country with adequate provisions will be much lower. The treatment is supportive, like most of what we do in the intensive care unit; there are no proven antivirals or miracle drugs, so fluid hydration, blood pressure and oxygen support, and blood transfusions are the mainstay of therapy. The other reason Ebola scares people is its name; it is the stuff of outbreak horror movies. I have talked to many people who are panicked about Ebola but my prediction is that this outbreak will take far fewer lives than influenza will this winter season, but will get much more press.

Image of nurses caring for a patient with Ebola from a 1976 Zaire outbreak is in the public domain, from Wikipedia.

Sunday, October 26, 2014

Ebola I - The Basics

I've been thinking about this topic for a while and procrastinating a bit to see where things go, but it's time to write this post. Ebola is coming. What it will look like, what it will mean, and whether it turns into the scare everyone's worried about remains to be seen, but there's no doubt about it, physicians and hospitals need to be prepared. I'm going to spend a few blogs writing about Ebola, not because it in itself is such a remarkable disease, but because its an outstanding case study in learning about the response to new and emerging infectious diseases, the globalization of health, the cultural context of disease, media and public response to threats, disaster preparation, and what it's like to be a physician for these patients.

First things first. Ebola was discovered in the mid-1970s so it's not a disease that's been around all that long. Its origins hint at where new diseases may come from: the transmission of viruses from animals to humans. Many recent infectious agents like HIV, swine flu, and avian flu have animal reservoirs, and perhaps this is what fascinates infectious disease and tropical medicine specialists. The exact host and viral life cycle are unknown so far, though evidence suggests a reservoir in bats. There have been over a dozen prior outbreaks, but each has been limited and has not caught global attention. In medical schools, Ebola and its related viruses are presented probably for five or ten minutes. After the 2014 outbreak, I am sure there will be more focus on it. This, also, is interesting; most physicians learn about Ebola by talking to the experts and reading the publications. I, certainly, was not well-versed in the disease, but when I found out I might be taking care of these patients, I started studying.

One challenge with Ebola is that its presentation is nonspecific; its symptoms could result from any number of diseases. Like most viral illnesses, it begins with fever, malaise, aches, and pains. Over the next few days, its symptoms move to the gastrointestinal tract with nausea, vomiting, and diarrhea. It kills patients due to severe dehydration and resulting metabolic disturbances and organ malperfusion. Diagnosing Ebola lies in the history: where has a patient traveled and who has he been in contact with? For now, while the outbreak remains in West Africa, screening patients is relatively easy, but if Ebola spreads to Europe or the United States, this will become a major problem.

Image is in the public domain, from Wikipedia.

Thursday, October 23, 2014

Things We Don't Know

It's easy to diagnose, treat, manage, write about, and describe things we know well. The majority of clinical situations, cases, patients, and procedures described in this blog are ones I feel very familiar and comfortable with. But perhaps the point of training is to learn about and become better at those clinical situations, cases, patients, and procedures which intimidate us. As an anesthesiologist, I feel well-versed in many things, but one of the clinical scenarios that scares me most is the hematology patient.

One reason the Stanford medical ICU is much higher acuity than the other ICUs we rotate through is the high prevalence of patients with bone marrow transplants, graft versus host disease, acute leukemia, tumor lysis syndrome, and serious reactions to antineoplastic agents. These are disease states we almost never see in anesthesia, so I rely heavily on my medicine colleagues, my consultants, and my reading to give me guidance. These patients can be incredibly sick and though I can manage supportive care - the vasopressors, dialysis, mechanical ventilation, antibiotics, transfusions - I don't know the hematology very well. This makes it hard for me to estimate prognosis, talk at family meetings, decide on when to pursue chemotherapy, and identify side effects of antineoplastic agents. As a result, it'll be a personal focus the next few months for me to gain a better understanding of hematologic illness and disease courses.

Image of acute myelogenous leukemia blood smear shown under Creative Commons Attribution Share-Alike License, from Wikipedia.

Tuesday, October 21, 2014

Why Anesthesiologists Matter

A middle aged man is brought to the emergency department for a fall and loss of consciousness. A stat CT scan of the brain shows a severe brain bleed, probably from uncontrolled high blood pressure. His neurologic exam is deteriorating; he doesn't wake up to voice or touch, and he cannot protect his windpipe, so the emergency physician determines that a breathing tube is necessary. As they make this determination, they call me as the ICU fellow and say they are going to admit the patient to my service.

Even though the emergency physicians have formulated an appropriate plan, I rush down because this will be my patient. When I arrive, the medications to ensure the patient is asleep for intubation have already been given. The ED physicians have used their standard agents for intubation, but they are absolutely not the ones I would choose. The medications they use are ideal for overwhelming infection, trauma, and massive bleeding because they maintain the blood pressure. But this person was bleeding into his head; as an anesthesiologist, I would have chosen medications that prevented a hypertensive crisis. Unfortunately, I arrived moments before I could give them feedback.

In this situation, everyone in the room was tense and stressed about getting the breathing tube in. But as an anesthesiologist, when I glanced at the patient, I was fairly confident I could do it without trouble. I kept my focus on the main thing that would kill this patient: his blood pressure, especially with the forceful ED laryngoscopy, would go through the roof, and this would dramatically worsen the bleeding. I grabbed propofol and labetalol, two agents to lower the blood pressure, but it took me several minutes to get the blood pressure into an acceptable range. I was the only one focused on those vital signs, and if I had not been there, critical time would have been lost. Here is a situation where an anesthesiologist matters.

Many people can put in breathing tubes. Emergency doctors, intensive care physicians, neonatologists, even emergency medical technicians can do the physical action. But I spent three years learning the nuances: how to minimize trauma, what medications to choose, what complications to expect, how to manage the whole patient while focused on one small task. No matter how good a non-anesthesiologist is, his training is simply not as focused on these critical few minutes, sending a patient to sleep and securing the windpipe. In this case, I think it mattered. I have a lot of respect for other specialties because they do things I know little about. I write this blog not to criticize them, but to say that as an anesthesia-trained ICU fellow, there are situations, procedures, and medical decisions I feel very confident about, and I hope we are recognized for those instances of expertise.

Sunday, October 19, 2014

Real Work Again

The month in the VA gave me a taste of perhaps what community ICU could be like. With only fifteen beds, patients and diseases that by ICU standards weren't too severe, and lots of teaching opportunities, it was the easy life. I thoroughly enjoyed introducing third month interns to the world of medicine, challenging my residents and mid-levels, and learning how to act an attending. VA calls were home calls, so I'd go home late in the evening and only occasionally be called back for admissions. I spent time not only studying and learning, but also taking care of myself and enjoying life.

Alas, such things cannot last. After the VA, I've been at the Stanford medical ICU, the paragon of medicine and one of the most exhausting rotations this year. When I started, I ran a team that had nearly twenty patients, and no matter how many we sent to the floor, we'd reaccumulate nigh instantly. As a fellow in the MICU, we have are own defined roles and don't take on as many attending responsibilities. I scurried about to multidisciplinary rounds, family meetings, and lectures. I occupied myself with supervising procedures, running codes, and admitting patients. The acuity these past few weeks has been quite high, and I've gathered a few interesting stories to blog about this week.

Saturday, October 18, 2014

Difficult Airway in the ICU

I've had my share of difficult airways in residency, but the difference now is that I ought to be fully independent with airway management. Of course there is an ICU attending, but that attending isn't always an anesthesiologist, and in those circumstances, I am the go-to airway person in the ICU.

The Palo Alto VA has a pretty amazing spinal cord unit; we have patients transferred from all over to get our expertise in management of spinal injuries. A middle-aged vet with a longstanding cervical spine injury and fusion has subacute respiratory failure. His mouth opening is poor and his large face and prominent beard would make mask delivery of oxygen challenging. After talking it over with the patient and his sister, we decide to intubate him to get him through his pneumonia. How do I proceed?

Normally, I would come up with a plan and then discuss it with my anesthesia attending, but here, I had the role of "airway." Most of my co-residents who are now attendings talk about becoming a little more conservative now that they are on their own. I did the same. With the difficult airway cart in place, I decided to induce anesthesia, put in a laryngeal mask airway, and ventilate through the airway. After I knew I could deliver oxygen, I proceeded to use a fiberoptic bronchoscope, visualize the vocal cords and windpipe, put a catheter there, and then use the catheter as a guide to place an endotracheal tube. I was sweating a little bit, but it went easily, and his lowest oxygen saturation was 99%.

A week later, we tried to extubate him, but unfortunately, he failed to maintain his airway on his own. I had to put the breathing tube back in. This time, though, I had a resident. I knew what worked for me last time and I was confident I could reintubate him if necessary, so I asked the resident what she wanted to do to put the breathing tube in. She decided to go with a throwback to the 1990s with a Patil-Syracuse mask. I had only used this once or twice, but I trusted her judgment. The seldom-used Patil mask is designed to allow delivery of positive pressure ventilation while the anesthesiologists secure the airway with a fiberoptic scope. We used it with our BIPAP machine and ensured that it had adequate oxygen delivery and ventilation prior to putting the patient to sleep. Since we could continuously breathe for the patient while guiding the flexible camera into the windpipe, we had all the time we needed. The anesthesia resident, one of the best ones I've ever worked with, did everything independently. This taught me a lot as an attending, to trust my resident's skills, to appreciate judgement decisions, and to have confidence that I could rescue the patient if things went wrong. Now that I'm an ICU fellow, I don't intubate all that much, but occasions like these are ever so exciting.

Thursday, October 16, 2014

Defying Augury

Although the acuity of the VA ICU patients is not as high as those in the "big house," we do occasionally get quite challenging medical mysteries. A patient with proven adrenal insufficiency by cortisol stim test simply cannot wean off stress dose steroids. In his month-long stay in the ICU, he kept on having recurring episodes of "sepsis." He has cyclic spikes in his temperature, drops in his blood pressure, and increases in his white count. He has multiple sources of infection including multiple indwelling lines, aspiration events, urinary infections, joint effusions, intraabdominal sources, and skin infections. Every time this happens, we increase his pressors, broaden his antibiotics, and put him on stress dose steroids. He gets better and after we get him off pressors, we start slowly inching back on his stress dose steroids and antibiotics. Soon thereafter, another episode happens and the cycle recurs again. It's frustrating because each bout of sepsis sets him back more and more, limiting his nutrition, accumulating insults to his organ systems. But we cannot keep him on high dose catabolic steroids and ultra-broad-spectrum antibiotics forever. His muscle mass has already wasted away and he's already had Clostridium dificile infections. We've consulted every service in the hospital and performed tests I rarely order like WBC scans. Yet he defies augury, and we simply cannot get him better. It's a sad story, and unfortunately, not an uncommon one in the ICU. It reminds me that modern medicine has its limitations.

Tuesday, October 14, 2014

General Surgery and the ICU

At the VA, we had a considerable number of general surgery patients on our ICU service. As an anesthesiologist, the post-operative care of surgical patients feels fairly manageable. But there were a number of remarkable critically ill general surgery patients who we treated on my month at the VA. Some were long-term players. One patient with multiple abdominal surgeries developed a persistent, severe hematuria - he was bleeding into his urine. For a week, our urologists worked to find the area of bleeding, but when one source was controlled, another became problematic. I don't usually think of hematuria as an ICU problem, but for this gentleman, nothing was a magic bullet. We put in nephrostomy tubes, used specialized urinary catheters, did continuous bladder irrigation, sent him to IR. Eventually, we achieved tenuous control of it and sent him to the floor. Another patient who refused to see a doctor came in with a perforated colon from metastatic colon cancer. As part of our ICU care, we had to involve the oncologists and palliative care doctors because adjusting to this new disease was going to be a big psychological shift and coping challenge. A separate vet with a perforated bowel had blueberries free-floating in his abdomen. The infectious and inflammatory response was so severe I had him on four vasopressors at one time, but we managed to tide him through. Another vet with a similar disease had breakdown of his abdominal wall so he had an open abdomen. His wound healing was so poor that the surgeons felt it would be months before they could close up his abdomen. 

Most of my year is focused on the medical intensive care unit and we simply do not see patients like this on that service. This month at the VA reminded me that a critical care physician must be well-rounded and prepared to take care of many, many different disease states and conditions.

Sunday, October 12, 2014

The Next Generation of Health Care Professionals

Along with a few other writers from The American Resident Project, I participated in a panel at the 12th annual UC Davis Pre-Medical and Pre-Health Professions National Conference. Sponsored by The American Resident Project, we got to meet premeds and recent graduates interested in going to medical school. The panel was chaired by Dr. Sam Nussbaum, and I really enjoyed the lively discussion we had. We covered topics like work-life balance, 30-hour calls, building patient-physician relationships, and challenges in residency. Over lunch, the panelists, Dr Nussbaum, and I mulled over some of the changes happening in health care, problems with our current delivery system, and possible innovations to meet our dynamic health care needs. The thought provoking day reminded me we cannot be complacent or passive; as physicians, we have an imperative to become leaders, tackle system problems, educate and inspire the next generation of physicians, and engage our communities. Although participating in a panel like this takes away one of those coveted days off, it is such an opportunity for me to ponder the bigger questions of health care with brilliant people.