Friday, October 20, 2017

Trying to Diagnose TB in the Hospital



When you suspect active TB when admitting a patient to the hospital, it turns out it is quite difficult to rule someone in or out. Here is a brief look at how you can get tricked trying to diagnose TB, and some recommendations for workup up these patients.

Skin test and quantiferon gold assay are bad at diagnosing active TB:
- Quant gold cannot exclude active (or latent) TB because 10-35% of patients with active TB will have a negative quant gold assay.
- The skin test will be negative in 50% of patients with disseminated disease and 5-40% of patients with pulmonary disease.
- This online latent test interpreter is excellent: http://www.tstin3d.com/en/calc.html

You really can't RULE OUT active TB with sputum tests. All you can do is have a certain degree of confidence about how many TB organisms are present in the patient's airways. If you have a negative sputum smear, you have detected down to a minimum of 5 thousand colony forming units (CFU)/mL. A negative sputum PCR detects down to 150 CFU/mL. A negative culture detects down to 10 CFU/mL.

Unfortunately, the culture takes weeks, so it's not helpful in the short term when admitting. Many hospitals don't have sputum PCR or Gene Expert testing. That usually leaves us with sputum smear. This will tell you something if the airways are teaming with organisms, but can be falsely negative for disseminated TB or for a lower burden of respiratory disease. The main thing that the negative sputum gives you is confidence that the patient is not contagious to the rest of the hospital.

Imaging is helpful, but also doesn't rule out TB. 5-15% of active pulm TB have negative CXR, CT is better but not absolute.

Takeaways:
- If you have even a low suspicion for pulm TB (A respiratory complaint in a patient from an endemic area, HIV, homeless/incarcerated, unexplained wt loss, etc), they need to be on airborne precautions.
- If the sputum smears are negative x3 (you can order them 12 hrs apart), you can be reasonably confident that they're not contagious.
- The skin test and quant gold assays can be negative, but still have pulm or disseminated TB, so they're not very helpful in the inpatient setting. It's worth testing because if positive, they will need TB clinic and likely treatment for at least latent TB and further workup for disseminated disease.
- Your main job in working up active TB is to protect the hospital, patients, their families and staff. An exposure affects hundreds of people, causes lots of hassle, and costs lots of money.

Friday, September 29, 2017

How urgent is hypertensive urgency?

How quickly do I have to lower blood pressure in “hypertensive urgency”?

The term hypertensive urgency was established in 1974 as SBP >180, DBP >110 without evidence of end organ damage, and recommended to “lower MAP by 20 over 24-48 hours” [1]. However, there has never been data to quantify the short term cardiovascular risk of hypertensive urgency, let alone the benefit of BP reduction in the short term.

Until now:
Characteristics and Outcomes of Patients Presenting with Hypertensive Urgency in the Office Setting. Patel et al. JAMA IM. 2016;176(7) [2]

Bottom line:
There was no significant difference in stroke or MI (Major Adverse Cardiac Events, MACE) between those admitted to the hospital for urgent management and observation vs. those sent home with uptitrated oral meds for patients with SBP >200.

Monday, May 2, 2016

The Medical Bait and Switch

Image result for thinking fast and slow


I just discovered a thinking fallacy featured in the book "Superforecasting." It happens all the time in medicine.

It's called the bait and switch. It's similar to anchoring, but different.

It happens when, confronted with a difficult and foreign problem, a person substitutes an easier-to-solve and more intuitive problem, and then answers that problem. 

When someone comes to the emergency room with shortness of breath, this is a complex problem with many, many possible causes, often mixed together. Rather then get to the bottom of this, we substitute shortness of breath with a simpler problem- pulmonary edema from heart failure. Mild pulmonary edema is a much easier problem than shortness of breath. We give a relatively harmless medicine, furosemide, quantify that we're making progress by measuring its effect on weight loss or negative fluid balance, and then dust our hands of the problem and congratulate ourselves on another job well done. 

Meanwhile, while hospitalized for a few days, the patient is removed from whatever insult caused the shortness of breath (maybe the mold in their apartment triggers asthma, or the challenges of insecure housing, nutrition or basic safety, or substance use). During that remove, they feel better and their shortness of breath improves. 

They feel especially better when suggested by their doctors' leading query: "Are you feeling better?" 

This is even more effective when phrased like "You've lost a liter of fluid and your chest X-ay is clear, are you breathing better?" Who could say no?


Tuesday, April 26, 2016

Five magnitudes of medical harm



Despite the dictum to do no harm, everyone agrees that medicine is harmful. But just how harmful is it?

Level 1- The unavoidable, almost necessary harm of practicing medicine.
Example: the pain and discomfort of surgical excision of a ruptured appendix. When slicing into someone's body, causing pain and discomfort simply cannot be avoided. The benefits of surgery dramatically outweigh these travails, and so we simply soldier on. In some ways, the doctor's role is to be the authority, the stoic bearer of bad news who unflinchingly faces the facts, and disregards these unavoidable harms so that they don't impede the grisly work that simply must be done. This role was probably prominent in the early days of medicine, before anesthesia, when on the battlefield, the qualities one wanted in a surgeon were grit and speed. This level can found among retired docs and scattered about a few naive young residents.

Level 2- The enterprise of medicine is more harmful than it seems.
This level is more humble than level one. It is sensitive to the fact that mistakes and pitfalls are everywhere, and they aren't always outweighed by medicine's benefits. It knows that bad things happen just by in the hospital. Reducing this harm depends chiefly on competence, on being a good doctor. Good doctors are careful, they know their craft and try very hard to make the correct diagnoses and perform their procedures with skill. As long as the doctor is diligent, there is a certain fatalism around bad outcomes. This level is embodied by the league of residency program directors and department chairs.

Level 3- Preventable harm exists on a large scale and requires changes in the systems of care.
These were described well in the Institute of Medicine's report "To Err is Human." It detailed the massive scale of health care induced harm (hospital acquired infection, medication error, etc), far exceeding the public and most physicians' worst estimates- over 100,000 preventable deaths a year. It was recognized that medical knowledge and clinical skill had little to do with it, and that the chief drivers or mortality were in the basics-hand hygiene, timeouts before procedures, checklists for surgery. Wide scale harm is a built into the system. Change the system, reduce the harm. And the quality improvement movement was born.

Level 4- The health care system is so broken and dysfunctional that dramatic action is warranted.
This level compares the ideal of health care as a human right that society makes available to all, like education and public safety, to the reality of health care as a deeply unfair, inaccessible and expensive wealth extraction system that serves the revenue streams of multinational pharmaceutical and device companies, large insurers, and sprawling hospital systems and physician organizations. This level seeks major structural changes, such as realigning payment incentives and legislation, to better serve the underserved- the poor, the elderly, the chronically ill. The single payer movement is a prime example of level 4.

Level 5- The health care system is more harmful than helpful.
This radical fringe believes that if all hospitals and doctors' offices were eliminated, society would live better and longer lives. They see harmful corruption and misinformation in almost every facet of health care, from the faulty evidence underlying common treatments and guidelines to the delivery of health care in profit-motivated institutions. When you add up the harm from medicalization of birth and death, overtreatment of most common conditions, and society's lost investment opportunities in education, housing, and public health, coupled with the unmeasurable but devastating crisis of human dignity visited upon more than one million nursing home residents crowded into close quarters, totally dependent on underpaid staff, living out their remaining days immobile in front of a TV, it's at least plausible that these harms outweigh health care's benefit. Proponents of level 5 are mainly found on the books with titles like "We're Doomed."

Friday, December 25, 2015

Is Healthcare a Human Right?





What do we mean when we say that healthcare is a human right?

The simplest case is that we mean what the United Nations means in the Universal Declaration of Human Rights:asdf

Article 25 
Everyone has the right to a standard of living adequate for the health and well-being of himself and of his family, including food, clothing, housing and medical care and necessary social services, and the right to security in the event of unemployment, sickness, disability, widowhood, old age or other lack of livelihood in circumstances beyond his control.

Critics claim that "just because the UN says it doesn't make it so."

Fair enough.

For me, the reason to support the concept of healthcare as a human right requires a simple thought experiment, "What kind of society do I want to live in?"

More specifically, "How do I want my society to respond to the sick?"

It's perhaps easiest to begin by describing how I certainly don't want my society to respond. I hope it's a comfortable assumption that I speak for most Americans when I say that allowing the sick to suffer and die, unaided in the street, is abhorrent. Although there are philosophical treatises underlying this position, I think we can save some time and simply agree that callous indifference to the suffering and vulnerable is unacceptable in 2015.

The real question is not whether or not our society is responsible for the sick and vulnerable, but how responsible is it?

Put another way; it's one thing to say that indifference is unacceptable. It's another thing to compel the citizenry to act on behalf of the vulnerable.

Fortunately, we already do act, and not out of any compulsion to do so. Anywhere in this country, bystanders routinely call 911 when they witness extremis, summoning the couriers of the emergency medical system to whisk them off to an emergency room replete with all the modern tools of resuscitation. Emergency rooms treat all comers, regardless of their background, their social status, or their ability to pay This is not a small thing, and for those who can sense a righteous tone that may be building in the paragraphs to come, let me say clearly that many wonderful people execute complex care coordination to provide this essential safety net.*

Emergency services are wonderful, but health requires much more than intervening at the point of desperation. How far should our society go?

For me, a simple answer is a comparison of our education system. Any child, regardless of the neighborhood they live in, their poverty, or even their beliefs about education, gets to go to school. It is an expectation. Their is a transport system established for those who don't have access. There are support services to help parents navigate the system. There is free lunch for those who need it. The US has provided every child with a right to an education.

I think we should do the same for health. There should be an expectation that anyone who is ill, regardless of where they live or how impoverished they are, can see a doctor. If they can't get themselves there transportation should be provided. There should be services to aid navigation. Beyond acute illness, patients should have access to preventive care and social supports.

Almost every other developed nation, and even some that are underdeveloped, has this. The US does not. Unlike other nations, one's access to healthcare depends on their proximity to a clinic (community health centers are closing), on the availability of basic services in that clinic (mental health is notably lacking in primary care), on patients' ability to navigate a complex system (talk to anyone trying to understand their medicare coverage), and last but certainly not least, on the ability to pay for both insurance and out-of-pocket fees.

Simply put, healthcare is not a right for the poor and marginalized in the US.


Any discussion of rights necessarily includes a discussion of responsibility. Rights are meaningless without responsibility. The right to life is the responsibility not to kill. More than that, it is the responsibility to set up mechanisms to prevent others from killing through laws and a police force. The right to education is a responsibility not only to not interfere with another's education, but to support students with teachers and infrastructure.

We all pay taxes to support the criminal justice system and the education system. In fact, if we don't, we can be put in jail. Society compels us to pay through threat of force.

When we hand out rights, we also hand out coercion, which paradoxically amounts to taking away rights. The right to life takes away my right not to be taxed for law and order. The right to education takes away my right not to pay school taxes.

Handing out rights is more than a dreamy exercise in imprinting our vision of the world in a high-minded list. It is also handing out obligation and responsibility, collected under threat of jail time. I can understand those who are resistant to the idea of a self-selected group of idealists sitting down at a convention and deciding which obligations the rest of us have.

So, when I say I want our society to treat healthcare like we treat education, I need to make the case to those who do not want to be saddled with the responsibilities of making this a reality.

Interestingly, those skeptics often spend a good deal of time extolling the virtues of this nation, its ideals, its strengths, and its standing as a moral force in the world. They trace this virtue back to the founding fathers and the provision of rights as set forth in the Constitution. This society has become what it is, still the envy of much of the world, because of its provision of rights. Human rights serve human dignity, and human dignity is the well-spring of human flourishing.

Look what happens when we provide our citizens with education?

We can only gain by doubling down on our commitment to health.