A Poor Predictor is Worse than No Predictor: On the Superiority of Empiricism in Some Medical Decisions

John Locke, empiricist.

The moral of this story is that much maligned empiricism is sometimes (often?) both the only thing to guide you and also the best thing to guide you.

I recently received a call (at an odd hour on the weekend) from an otolaryngologist (ENT) regarding a patient from whom she had drained a large submandibular abcess.  She was calling to tell me that she planned to leave the patient intubated in the ICU overnight and she wanted "help with ventilator management" (which of course the patient does not need - he can be managed with an endotracheal tube not connected to any mechanical ventilator).  The patient did not have airway compromise or concerns thereof prior to surgery, but, she said, there was swelling noted after the case that (for her) raised concerns about the patency of the patient's airway if the endotracheal tube were to be removed.

(There is a second moral to this story: far too often, patients such as this are left intubated post-operatively not for their own safety, but rather for the convenience of surgeons and anesthesiologists who do not wish to spend the extra time awakening them from anesthesia and observing them carefully in the post-anesthesia care unit.  It is far easier to not fret over the depth of anesthesia, atelectasis, oxygen levels, fluid status, and leave the patient intubated and send them to the ICU and let somebody else sort it out.  If I had a family member undergo a relatively routine, even if urgent or emergent operation at an odd hour [holidays, weekends, after hours] and they were sent to the ICU post-op for no apparently good reason, there would be hell to pay.  Note also that for the surgeon and anesthesiologist to save an hour of their time, another physician has to drive to the hospital to take over for them spending hours of his time, and also often a nurse must be called in from home to accommodate the unexpected post-op admission [as was the case here].  The sheer arrogance and egocnetricity of this is mind-boggling.  But I digress.)

Back to the story.  I naturally inquired as to what criteria we would use the next day to determine if the patient's oropharyngeal swelling had abated sufficiently such that we could safely extubate him.  The ENT replied that she would scope (endoscopy) the patient again in the morning and if the swelling had decreased we could proceed with extubation (removing the endotracheal tube).  Well and good.  Or is it?

Accidental Survival from Beneficent Neglect: When "There's Nothing More We Can Do" Becomes Your Salvation

"There's nothing more we can do", according to this NYT article, is a terrible thing for a physician to say to a patient or his family member, even if the intention is much needed candor.

Yet sometimes, a physician's resignation or a patient's refusal becomes the patient's salvation.  There is something to be learned about the futility of many of our treatments and our arrogant ignorance of our impotence in many situations.  Several examples, I hope, will cause physicians to reflect on many of our practices.

A study showing that cancer patients choosing palliative care outlived those choosing aggressive care should have caused a lot of introspection about the possibility that many things we do harm rather than help patients.  How are we to know?  In the ICU, we have several unique opportunities to observe the futility or downright harm of many things we do.

A young woman came to the ICU with mental status changes, an EEG was ordered, and a diagnosis of "non-convulsive status epilepticus" (NCSE) was made.  She was intubated and heavily sedated and treated with every manner of anticonvulsant and CNS depressants and coma-inducing agents.  The EEG continued to show, according to the report, NCSE two weeks later.  The family was told that "there's nothing more we can do" and a decision was made to stop all therapy and withdraw care and prepare to send her to hospice.  This was done, but over the next 24 hours, she awakened and was alert and oriented. She walked out of the hospital later that week.

Technological Crutches and Agenesis and Atrophy of Procedural Skills

This article in the New York Times describes the possibility that with increasing reliance on technology and automation, there is atrophy of human skillsets which can lead to untoward outcomes, especially when technology fails and humans have to take back the steering wheel.  One example it called upon was a crash in 2009 of an Air France jetliner that was caused by icing over of the airspeed sensors upon which the autopilot program relied.  When the autopilot failed and the pilots took over, they were confused and ill prepared, and the plane crashed into the Atlantic Ocean.

I am no general fan of romanticizing dated technology (except for the pager) such as the physical examination when superior and ubiquitous technology supercedes it.  Spending five or ten minutes flipping the patient into different contortions trying to identify a gallop or a subtle murmur seems quixotic if an echo has been ordered or the result is pending (although if this interests you as it did me, indulge yourself, its performance and ponderment reinforces the underlying physiology poignantly).  On the other hand, if a patient in the coronary care unit crumps and you cannot identify the obvious holosystolic murmur from a chordae rupture….

I am reminded specifically of certain technological crutches graduates of internal medicine and critical care training programs have come to depend upon in the past decade such as ultrasounds for the placement of central lines and performance of thoracenteses, and fiberoptic aids for endotracheal intubations.  These devices certainly have a role in both training and patient care, and I am generally familiar with the favorable data on success and complication rates, but something is certainly lost when a trainee’s or a practitioner’s efficacy is overly dependent upon use of these technological crutches.

What to do during a Code Blue on the floor when there is no ultrasound and no intravenous access?  I recall several Code Blues where I inserted a subclavian line during brief epochs when chest compressions were held, but it is not uncommon nowadays that trainees leave a critical care fellowship with no proficiency in the subclavian approach whatsoever (or worse, that they learned erroneously that the jugular approach is generally superior to the subclavian approach).  What to do when there is a Code Blue but the Glidescope is in the ER, or there is no Glidescope, the Glidescope malfunctions, or there is a Glidescope but there is also a GI bleed or profuse vomiting and no fiberoptic visibility?  How can you know how to instinctually position the head and neck for a direct view of the larynx if you have trained almost exclusively on a device that obviates a direct view of the larynx?  How do you percuss and tap a pleural effusion when there is no ultrasound available if you have learned this procedure by the “point and poke” method?

One approach to this problem is to insist that trainees learn the tried and true methods first, and resort to the technological aids only for difficult cases or those in which the simple methods have failed.  Make an attempt with the Miller 2 blade (one brief attempt) and if that fails, proceed to the Glidescope.  Identify the internal jugular using proper patient positioning and identification of anatomical landmarks and make a pass with the finder needle before resorting to the use of the ultrasound, or use the ultrasound to confirm or refute your estimation of the jugular position prior to making a pass, rather than relying on it from the get-go.  In this way, the technology can be a way to calibrate predictions and can enhance learning of the underlying basic techniques, while also bolstering proficiency in their performance, and increasing optionality in procedural approaches.

Even with widespread availability of echocardiograms, cardiologists must be able to identify basic murmurs.  If trainees are leaving their programs where 90% or more of their procedures were performed with a technological crutch or aid, they may have rude awakenings when atrophy of basic skills (or the absence of their development) becomes apparent during exigent circumstances in real world settings.

Bayes' Theorem Explained, No Math Required

I was asked by a medical student to explain Bayes' Theorem.  This blog is about lack of common sense in medicine, so it follows that education about first principles will contribute to uncommon sense, and I will oblige.

Bayes' theorem is simply a long or holistic way of looking at the world, one which is more in keeping with reality than the competing frequentist approach.  A Bayesian (a person who subscribes to the logic of Bayes' Theorem) looks at the totality of the data, whereas a frequentist is concerned with just a specific slice of the data such as a test or a discrete dataset.  Frequentist hypothesis testing is where we get P-values from.  Frequentists are concerned with just the data from the current study.  Bayesians are concerned with the totality of the data, and they do meta-analyses, combining data from as many sources as they can.  (But alas they are still reluctant frequentists, because they insist on combining only frequentist datasets, and shun attempts to incorporate more amorphous data such as "what is the likelihood of something like this based on common sense?")

Consider a trial of orange juice (OJ) for the treatment of sepsis.  Suppose that 300 patients are enrolled and orange juice reduces sepsis mortality from 50% to 20% with P<0.001.  The frequentist says "if the null hypothesis is true and there is no effect of orange juice in sepsis, the probability of finding a difference as great or greater than what was found between orange juice and placebo is less than 0.001; thus we reject the null hypothesis."  The frequentist, on the basis of this trial, believes that orange juice is a thaumaturgical cure for sepsis.  But the frequentist is wrong.

Countless Hours, Part 3: Uncalibrated Interns and Immediate and Accurate Feedback

Immediate, accurate feedback begets calibration

In this third and final installment of Countless Hours:  How to Become a Stellar Student and An Incredible Intern, I will discuss the role of immediate and accurate feedback for the refinement of a skill, prediction, or prognostication to expert levels.

Imagine you are learning to play golf, but you can't see where your balls are going - it would be very difficult, without any feedback to learn to modify your swing to improve your game.  Similarly, if the feedback you received were from an observer with poor vision, and it was not accurate, you would be trying to calibrate your swing to unreliable information and your game would not improve insomuch as the feedback was inaccurate.  Finally, if you did not receive the feedback on your swings until days later, it would be difficult to analyze it and adapt your game to it, compared with iterative feedback incorporated after each swing.

The same principles apply to learning the practice of medicine.  One of the reasons that the case study books mentioned in the previous post are so instructive is that they provide immediate, and accurate feedback - you get to know if your diagnosis was correct immediately after rendering it, and this feedback, from the experts who wrote the book (often with formal or informal peer review and editing), is presumably as accurate as you can hope for.  Thus, case based practice is a very very effective way to become an expert.

Then there is the "hands on" work you do on the wards and in clinic.  Here, feedback is, on average, less immediate, and less accurate, and this is one of the ways your learning in "real life" scenarios is compromised - but there are several things you can do about it to maximize the immediacy and accuracy of feedback in these environments.

Countless Hours: How to Become a Stellar Student and an Incredible Intern, Part 2: Iterative Practice

Iterative practice is the second component of becoming an expert at medical diagnosis or therapeutics (or, arguably, anything).  It is what you begin to do in the third year of medical school after you have mastered the domain specific knowledge of medicine.  And, the more you practice, the more experience you get, the better you will become, especially with immediate, accurate feedback (the topic of Part 3 of this series).

The need to see many many cases during your training so you can get lots of practice has been undermined in the last 10 years as efforts to limit "work hours" has scaled back the volume of patients interns and residents see.  I think this has created a deficit, and I wager that graduates are leaving residencies less prepared (and more entitled) than in the past.  If the problem was hours worked, it was not the volume of patients that was at its root, but rather the horse manure scut work that medical students and residents were expected to do as low wage and low status workers in the system.  Scut work has no meaningful educational value.  You should try to minimize scut work as much as possible, without drawing accusations that you're "not a team player" (a euphemism for "he fails to accept our prostitution of him") so that you can focus on meaningful learning.  Sadly, scut work will always be a part of the culture of medicine, but make no mistake, it is the enemy of learning.  Running a sample to the lab is hardly more educational than cleaning the men's room because the hospital won't hire enough janitors.

Fortunately, there are ways to get iterative practice, lots of it, without the distractions of scut work, if you can escape the wards when you're not doing meaningful patient care activities with associated learning opportunities.  On my third year rotation, I used to sneak off to the medical library in the hospital and go through old issues of Chest, looking for the "Pearls" section in the back of each issue, and read the brief case summary and try to figure it out.  The answer and a brief discussion were on the second page of the case.  If "working up" a new admission takes 3 hours and you can read a Chest Pearl in 10 minutes, reading the Pearl is 20 times more efficient than working on the wards.  Moreover, as a medical student, you are often told or you overhear the diagnosis before you even see a new patient, so it is NOT an unknown case, and it does NOT qualify for iterative practice of diagnosis.  It has value to work up that patient from the perspective of eliciting the history and physical exam, organizing the narrative, and making the presentation to your superiors, but make no mistake, you are NOT practicing diagnosis when the diagnosis is known.

I soon learned that Sahn and Heffner, the editors of the Chest Pearls, began a book series called Pearls.  I bought and devoured almost every one they published (except Sleep Pearls and TB Pearls - in keeping with what I said above, they were not unknowns and were thus not valuable to me - you knew every case was going to be Sleep Apnea or TB!).  I also discovered these little picture books that the British put out, one after another called Diagnostic Picture Tests in Clinical Medicine, that have just an image of a rash, a deformity, a physical finding, an image, a slide, whatever, with the answer on the next page.  They are awesome little books - I think I bought 30 or more of them (and they are going cheap on Amazon right now, so get on it!)  By going through these Pearls and Picture Tests books during Med 3 and Med 4 (hint:  Picture Tests fit in your coat pocket, so when you're "hurrying up to wait on the wards", you can study them), I "saw" literally thousands of unknown cases (with immediate, accurate feedback), literally the epitome of efficient, expert learning and iterative practice.  Because of this, by the time I got to internship, many many things were simple, rapid pattern recognition for me.  It was like I was years ahead of my training as a result of this kind of study.  I have not recently looked, but I would bet that nowadays, the palette of such unknown case practice books has expanded significantly.

Besides asking to take on more patients during your rotations (at the risk of being labelled a "gunner" - which is utter complete hogwash, by the way - you are not gunning for anybody, you just want to be the best physician you can be.  But you have been warned - being labelled a gunner can have impacts on your social reputation and thus your rotation evaluations, so conceal your "gunner" instincts if you can), there are other things you can do to enhance your learning opportunities.  One is to not blow off 4th year.  Fifteen years ago it was common to take easy "elective" rotations during the fourth year and travel and party a lot before the hard work of internship begins.  Do NOT do this.  I signed up for sub-internships, FOUR of them (maybe five, I don't remember).  I did the usual Sub-I in cardiology, but also did two in Critical Care (one at my medical school, another at the Cleveland Clinic), and finally a Hepatology Sub-I.  I recognized that there was a lot to learn in cardiology and in the ICU that I could not learn from my case books, and I wanted every opportunity to master those skills before internship, so I could, to my own satisfaction, take care of those patients as an intern.  I changed an elective rotation to a Sub-I in hepatology when, after my MICU rotation, I realized that I was still "scared of" bleeding - that is, nothing I had ever read about in my books or seen up until then on my rotations had prepared me for what to do on a practical level when a patient is "bleeding out".  (I learned on that hepatology rotation that it is actually quite simple, you get big IVs in place and order a lot of blood products.)  Sub-Internships are far more efficient learning rotations than are the third year rotations because you know more and you're more effective, and as a result "they 'let you' do more."  They were very very enriching experiences and they helped tremendously to prepare me for internship and residency.  I suggest you fill your fourth year with as many "hard core" rotations (such as Sub-Internships) as you can to maximize your opportunities for dense, meaningful iterative practice.  It pays off in spades during internship and residence, trust me.

Do it however you must, but "see" as many patients as you can, whether on the wards or in case or picture test books.  But make sure the feedback you get on the accuracy of your predictions and diagnoses is both immediate and accurate - the subject of Part 3 of this series.

Countless Hours: How to Become a Stellar Student and an Incredible Intern, Part 1: Domain Specific Knowledge

In his book Outliers, Malcolm Gladwell popularized the idea that to get really, really good at something, you need to work at it for 10,000 hours.  Some debate surrounds the validity of the 10000 hour rule, but I accept it because it dovetails with the theory of expert decision making in terms of prediction, which I think is representative of medical diagnosis.  (The rule would also seem to apply to fields that require technical skill such as surgery - the more Whipples you do, the better you become at doing Whipples.)  In order to become a good predictor (the best ones are weather forecasters, professional bridge players, and horse race handicappers, by the way, for reasons I will touch on below) you need three things (besides base intelligence)

1. Domain Specific Knowledge
2. Iterative practice, the more the better
3. Immediate, accurate feedback

I will discuss each of these in three parts in this mini series, with critical commentary on how "the system" does either a good or a poor job of promoting them, and give suggestions on how to supplement the system to do even better.

Domain Specific Knowledge:  This is what you learn in the first two years of medical school in a structured way, and thereafter in a less structured way.  It is impossible to overemphasize how important most of this information is, with some variance depending on specialty (embryology did me absolutely no good, but if I had pursued OB/GYN it may have been crucial).  One of the best things you can do to foster basic knowledge and its retention during the first two years of medical school is to buy the board review books from the outset.  There are seven (give or take) sections of USMLE Step 1, and you can get a review book for each of them.  (BRS Pathology, BRS Physiology, BRS Behavioral Sciences, A&L Medical Microbiology and Immunology, A&L Pharmacology, A&L BioChemistry were my preferred ones.)  If you study these books while you first learn the material, they serve as an ongoing review of that material, and point out gaps in what they're teaching you in medical school lectures.  But more important, when you go to study for Step 1 after the second year, it will be a relative breeze because you're familiar with the review materials and their organization, and have made annotations and cross references in them and will have figured out anything that you would have struggled with the first time through the books.  Almost every person who has followed this recommendation after I gave it to them (it was given to me by a good friend a year ahead of me, bless him) has scored in the top decile on boards and many of them in the top percentile (scores over 250 - you know who you are).

But the studying does not end there.  You must continue to read through years 3 and 4, internship, residency, fellowship, and thereafter.  I am perhaps an extreme example, but my example can give you an idea of the upper limit that a person can take it to.  I read the 13th edition of Harrison's Principles of Internal Medicine from cover to cover during Med 3, again cover to cover during Med 4, and I read the 14th edition cover to cover during internship and almost made it through again during residency.  I also did the Harrison's and the Cecil's board question books during medical school, as well as any other question set I could get my hands on.  That's right, I was studying for Internal Medicine Boards as a medical student.  During Med 3 and Med 4 I also read Principles of Critical Care, Critical Care Medicine The Essentials, and about 70% of Braunwald's Textbook of Cardiovascular Medicine.  I even bought Principles and Practice of Infectious Disease, but I didn't make it very far through that, and sold it before parting for internship.  And this list is not comprehensive, there were many more books and study guides and reviews I read, basically anything I could get my hands on.  I studied day in and day out, weekends and evenings, on rotations, on vacations.  And it paid off in spades in many many ways.  There was hardly a disease, a syndrome, a drug, a device that I was not familiar with when I first encountered it, and any case I did encounter was a far richer learning experience because I was able to see so much more nuance, so much more subtlety because of the preparation I had done far ahead of time.

The system does a relatively good job of structured knowledge education for the first two years, but it largely falls apart after that, and during the 3rd and 4th years and thereafter, you are expected to just absorb knowledge and experience, or to read in an unstructured way "about your patients".  In my opinion, this unstructured approach does not work optimally, because if you're just reading about lupus on www.uptodate.com (a very good resource, by the way) when you see a lupus patient you will a.) not be able to competently handle your first case of anything; b.) only learn about what you have seen; c.) not be able to diagnose things on the fly.   Many things you will never see in your training or your career, but you must still be familiar with them.

In the next parts, I will segue to iterative practice and immediate, accurate feedback.

The Medical History as an Exposure Narrative: A Didactic for Medical Students and Young Physicians

I just received an email from a medical student on the other side of the pond asking for my advice for junior doctors for learning the practice of medicine.  I will oblige.  When students are taught how to take a medical history, they are taught a rote sequence and its components, but are not taught what the point really is, why we ask certain questions, how we string the answers together, which components need more or less emphasis in a given case.  Here I will present a framework for that understanding, which may make history taking more meaningful and useful for those learning and refining it.

What we are really trying to do with history taking is to make a narrative of the patient's exposures in his or her environment.  This exposure narrative allows us to use Bayes' Theorem to determine the most likely causes for a given chief complaint.  Bayes Theorem should be reviewed for its own sake in order to understand its use here and elsewhere, but simply understanding that the base rate of a disease in a certain population is the "prior probability" of that disease in a patient will suffice for now.  So, if I asked you what mammal you are likely to see on your hike in the Rocky Mountains, you will list squirrel and deer and elk before mountain lion and badger.  It's just common to see deer and elk there.  In the jungle, or the desert, the answers would be different - because different animals have different probabilities in different environments.  Likewise, when a 70-year-old comes with pain in the joints, osteo- and rheumatoid arthritis are more likely than lupus and juvenile rheumatoid arthritis, which would have higher probabilities in younger patients.  Thus, age is an exposure, perhaps one of the most important ones, and this is why a student's presentation often begins with something like "Mr. Jones is a 78-year-old man..."  (It is also why I frequently interrupt physicians who call me to admit a patient or consult on one, because I can't begin to order the probabilities until I know the age of the patient, which they frequently omit because of indolence.)  The older person has been exposed to wear and tear on the body for a longer time, and this figures prominently in the probabilities of the diseases that s/he is likely to have.

Running AMOC: How the ABIM Sowed the Seeds of Its Own Destruction

As I preciently predicted, in response to the ABIM's MOC mandates, a group of enterprising physicians has created a new certification board for internists, and today ABIM appears to have relented at least a little bit in response to the threat of competition.  David has brought Goliath to his knees by hitting him where it hurts - in the pocketbook - and Goliath is literally begging for mercy.

But hold on kids, the credits are not rolling and this battle is not over.  ABIM has not done away with MOC, they are just backpedaling - for now.  And conspicuously absent from the mea culpa sent out by their president, Richard Baron, is any mention of cost effectiveness, cost containment, or cost reform.  One of the biggest benefits of the new board, besides less onerous busywork requirements, is that it saves you upwards of 90% in certification fees.

And make no mistake, this is all about money, my friends.  Just three short weeks ago, the ABIM staunchly defended its position and MOC requirements in this NEJM piece that was published alongside this piece by the architect of the new board, Paul Teirstein.  Why the change in heart?  The answer is quite simple:  math and money.  20,000 physicians signed the petition against the MOC requirements.  If just those 20,000 physicians jump ship and join the new board, the ABIM stands to lose tens of millions of dollars in revenue.  So it is no coincidence that the same ogrenization that two weeks ago thumped on its chest backed down today, just one week after the new board opened for applications.

Surely, the ABIM has calculated that it can arrest the mutiny "aboard" the ship before all is lost if it acts quickly and placates and appeases its diplomates with lipservice and token concessions.  I am reminded of the cheating girlfriend (or boyfriend).  You discover her infidelity and jump ship.  Then, when her romantic liaison turns sour, she comes crawling back to you begging for forgiveness and promising to never do it again.  But now that she has shown you her stripes and you know what she is capable of, you know better than to ever trust this conniving, duplicitous wo/man ever again.

And so let it be with ABIM.  I encourage all physicians to sign up for the new board.  The cost is nominal, just $169 for two years.  That is a small price to pay for a back-up plan as we wait to see if ABIM will make good on the promises outlined in the mea culpa issued today.  And even if it does, I'm already "aboard" the new ship - the cost savings alone are reason enough to make the change.

Specious Ideas: Trending Troponins and Chasing Lactates

I want to use this post to discuss an article in this week's JAMA called Lactate in Sepsis, which I think is fatally flawed and misleading.  But first...

Several years ago on the Medical Evidence Blog I talked about cardiac troponins and how their use is often misguided.  Not long after this post a young woman e-mailed me to describe a diagnostic and therapeutic misadventure that ensued after an abnormal troponin was "discovered" during work-up for a urological problem.  This led to transfer to another facility via ambulance for a cardiac catheterization with multiple complications including stroke.  It was a sad and unfortunate tale, but I fear it is not too uncommon.

Troponin, like all tests, needs to be ordered on the basis of a clinical suspicion (prior probability) that, when combined with the likelihood ratio of the test using Bayes Theorem (see calculator on the right of the blog), results in a posterior probability of disease that crosses a decision threshold.  (Because of the woeful inadequacy of medical education in regards to basic decision theory, I would not be surprised if the majority of physicians cannot correctly describe priors, Bayes, posteriors, or decision thresholds.  But this is old news, and beyond the scope of this post.)  The low prior probability of acute coronary syndromes in critically ill patients with non-cardiac primary diagnoses (PE, AECOPD, sepsis, etc.) leads me to list "non-specific troponin increase in the setting of critical illness" as a problem (an artificially begotten one) in my assessments after colleagues regretfully order tests that should never have been ordered.  And I will defer discussion of all those d-dimers and the needless CT angiograms they engender, lest I descend into unmitigated belligerence.

Plethora And Other Reasons Not to Donate Blood (Even if You Are a Gay Male)

Plethora is an excess of something, used in medicine usually to refer to a fluid, especially blood.  Plethoric facies describes a flushed and full red face, overfull with blood.

And so it is with the Red Cross.  It has become plethoric as detailed in this New York Times article from back in August.  Fortunately, we are giving fewer transfusions in medicine, perhaps at long last internalizing the data from the heft of recent studies on the lack of benefits of transfusions in multiple arenas.  This decline in transfusions has led to a surfeit of blood and falling prices per unit, which is leading the Red Cross to hemorrhage employees.

I want to use this post to convince you that you should reconsider whether or not to donate (or transfuse) blood.  Why would a person donate blood anyway?  "Because it's the right thing to do," comes the reply.  Why would a person think that?

Saith the A-line of the Swan: "There but for the grace of God go I"

I never never never, well, hardly ever use arterial lines (A-lines) anymore.  I just don't need them.  The nurses want them, but I mostly refuse, except in in extremis patients with labile pressures on high dose vasopressors.  (I also rarely "float" that Big Yellow Bird the Swan Ganz catheter.  It simply is rare that it provides information that is useful to me.)  Here are some reasons:

• A-lines increase the volume of blood drawn (and wasted) for laboratory testing, much of which is gratuitous at best, useless or harmful at worst
• They further limit already limited patient mobility - of an arm no less - and they are an impediment to getting patients out of bed
• They fail quite often.  I have yet to determine if this is nursing and RT related or the companies are using different construction that reduces catheter integrity - if you have an opinion on this please comment below
• They are one more invasive device on the list of potential sources of fever - the narrower this differential is, the better
• They are not obviously more useful than a non-invasive blood pressure cuff
• They have all the obvious attendant complications of an invasive device.

So I was happy to see the commentary piece in the November 2014 issue of Chest by Allan Garland calling for RCTs of A-lines (a less measured person may have invoked a moratorium on them).  His piece focuses on the lack of data for them, but gives a nod to the notion of "blind acceptance" of established practices, and status quo bias.  Most critical care physicians trained in largish academic centers where their use is commonplace, whether because of tradition, the desire of senior house officers to teach junior ones (hey, you gotta get your numbers up in your procedure booklet somehow), remuneration for procedures in private practice, or other biases.

If you have not already, for the next few months, try to resist the pleas and sirens beseeching you to place an A-line so that you can experience the alternative reality of an A-line free ICU - if you do, and you pay careful attention, I bet you too will find that they are unnecessary and that the threshold for inserting them should be high and the threshold for removing them should be low.

(John Bradford uttered something like "There but for the Grace of God go I" as he watched a criminal being led to execution - in recognition that the potential for human sin lies in all men.)

The Slave, the Master, Captain Obvious, and Insatiable Searching

I'm going to use some cheeky analogies to prove some points in today's quick post.

Imagine that while you are away, your fire alarm goes off, and the fire trucks come, sirens ablaze.  After an investigation, the brave men in blue determine that there is no emergency, every thing is in order, no fire.  They return to their station and not long later your alarm sounds again.  And again.  And again.  Should they douse your home with water just in case they're missing something?  Or should you disable your alarm?

Recently, I was consulted to assist with "vent management".  A patient was "fighting the vent" and was not ventilating well, with a pH of 7.03.  I arrive and find her deeply sedated on propofol and fentanyl (attempts to kill the fight in her) and breathing slowly at a rate of 8 (hence the low pH and high pCO2.)  Every ventilator mode has been tried, but she "breath stacks" or otherwise "fights the vent" without heavy sedation, which itself depresses respiratory drive so much that she gets a respiratory acidosis.  Turn up the rate, and she's back to "breath stacking."  But alas, she was not fighting the vent at all, she was fighting its alarms and it was fighting her.  A post-operative patient, she had low respiratory system compliance (her chest was stiff) and she was also not relaxing after the initial breath delivery, setting off the alarm and the inspiratory delivery, not exhaling, then taking another breath on top of the prior incomplete one.  Raising the peak pressure limit alarm to 60 stopped this and allowed discontinuation of most of the sedatives.  Now she accepts the breath, albeit at a higher peak pressure.  So was solved the problem that never existed, but was created by the alarm settings and the misguided responses to them. One should always ask oneself as regards ventilator alarms "Who is the slave and who is the master?"

The police are sometimes accused of settling prematurely on a suspect, at the exclusion of other possibilities, thereby leaving the real perpetrator free to commit other crimes.  In medicine we would call this premature closure, or search satisficing.  But the opposite of that may be delayed closure or insatiable searching.  Imagine that we have a prime suspect with a motive, and have video evidence of the crime - we can see whodunnit, and there is no evidence of accomplices or other conspiracies.  What police chief would allow his detectives to waste resources going out trying to find other possible suspects in this case?

Now, suppose a previously healthy young woman is exanguinating and goes into shock and multisystem organ failure during her resuscitation and massive transfusion.  Her LFTs (Liver Function Tests) go through the roof, as is seen in shock causing "shock liver".  Why on Earth would a provider order a viral hepatitis panel and an autoimmune panel in this patient?  What are the chances that this exanguinating trauma patient coincidentally has viral hepatitis instead of or on top shock liver?

A young patient with normal renal function develops post-operative shock and renal failure.  Should you order a renal ultrasound to check for obstruction?  What are the chances this patient has a predictable complication and spontaneous urinary obstruction or obstruction instead of the usual complications from shock?

A patient has a witnessed aspiration, say, from overdose.  There are bilateral infiltrates on CXR.  "But we should get a CT, maybe he has PE (pulmonary embolism), too."  And maybe he's gestating an alien fetus in his cecum.

Sometimes Captain Obvious needs to come rescue us from insatiable searching.

Utter Rubbish: A Call for a Moratorium on the 4 AM Blood Draw

The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself.  Therefore all progress depends on the unreasonable man.  - George Bernard Shaw

Depending on the week and the driver, I am often awakened around 4 AM when one of several delivery trucks backs into the driveway of the restaurant beside my house, 15 feet from my bedroom.  Rankled, I have been known to open the window and have words with the driver, who, in my opinion, should park on the street, thus creating a distance between our house and his beeping, rattling, diesel-idling, polluting truck with its slamming ramps and gates and whatnot.  Because he mindlessly prioritizes a minute or so of his time over my and my wife's uninterrupted sleep.  Sometimes, we just get back to sleep before the next truck comes and awakens us again.

In relating this story to my father, he told me that the residents of a Northeast Ohio municipality recently passed a city ordinance banning the picking up of garbage before a certain hour, because of complaints of the noise and disturbance that the rubbish trucks cause at earlier hours.  Immediately drawing the analogy of the 4 AM phlebotomy visit in the hospital, my father wonders why, in the era of customer service, we subject the sick of society to this indignity and injustice while they're in the hospital.  And the answer is that I don't know.  A quick Google search is of little help.

There are two likely and possibly related reasons for the 4 AM blood draw.  First, in days of yore, physicians rounded very early in the hospital and then went to their office or to the operating room.  They wanted the lab results by the time they rounded so they could complete the rounding task and move on to others and not worry what Mrs. Jones' creatinine was all morning.  So, in essence, we have historically been awakening patients at 4 AM for physicians' convenience.

Helping Those Who Won't Help Themselves: The Role of Personal Responsibility in Medicine

Give a man a fish, or teach him to fish.

It is a well known secret in medicine:  many of those we care for are unconcerned with their own care, as evidenced by their revealed preferences.  "What medications are you on?" the physician asks.  "I don't know, doc," comes the reply.  "Why are you on carvedilol?"  "I don't know."  "What was your last HgbA1C?"  "What's that?"  We have encouraged physicians and other professionals in the healthcare system to take responsibility for every aspect of patient's care to the peril of patients' own interest and investment in their care.  How often do you enter a room and find a patient researching their illness and its treatment, rather than surfing the internet or watching TV?  Is your patient more concerned with the timing of the next dose of antibiotic or the next dose of dilaudid?  How often do your patients keep detailed records of their past medical history?  Why does the intern or resident or PA or NP schedule follow-up appointments for patients, rather than the patients do it themselves prior to discharge?  Why must so many patients be coaxed out of bed and working with physical therapy?  The actions of patients reveal their preferences.  Those who are invested in their own care take responsibility for it and are knowledgeable.  Those who would rather watch television than work with physical therapy reveal other priorities and preferences.

All the hubbub about healthcare and health disparities has entirely glossed over the role of personal responsibility and accountability in medicine.  Some may find it inexcusable that many patients have so little investment in their own health care, expecting instead that the government, their insurance company, and the healthcare system at large allows them to abdicate their own personal responsibility without consequences.
(I am not here referring to people who are unable to care for themselves, but rather those who are perfectly capable but who shirk the responsibilities.  If you cannot accept this and wish to accuse the author of "blaming the victim" read no further.  Yes, the victim of disease is being blamed for any lack of personal responsibility that is contributing to poor health.)

If there is a lack of personal responsibility in medicine, there are several important implications that we should be concerned about.

Mindless Medicine: The Importance of Minding Your P's and C's

I see far too much mental laziness in medical practice these days.  I will give some examples below.

To teach the residents mindfulness in diagnostics and therapeutics, I used to tell them to mind their P's and C's:

• Problem:  What is the major malfunction that we are dealing with?
• Proof:  Do we have proof of the problem or diagnosis?  Is there uncertainty, or are there other possibilities?
• Cause:  How did this problem come to be?  Why is this happening?  Is there a deeper cause?  An even deeper one?
• Cure:  What interventions should be employed to treat the problem(s) identified?

Sometimes I receive a call from the ER to admit a patient and the "presentation" if you would call it that amounts to rattling off a list of the laboratory abnormalities.  "What is the problem?" I ask.  "He's going to have to come in," is the reply.  No, my friend, moving the patient out of the ED is YOUR problem.  I'm asking what is the PATIENT'S problem.  You are here, after all, to serve the patient, right?  Some ERs appear to be evolving into glorified triage centers, with a primary focus on differentiating those who can be sent home, flown out, or admitted, rather than centers focused on making expedient and prompt provisional diagnoses so that time sensitive therapies can be administered post haste.

We Must Suffer: Moral Hazard in Modern Medicine

I was first introduced to the concept of moral hazard in Rich Rubin's book In an Uncertain World.  He describes the deliberations within the Treasury and the Executive branch during the Mexican and Asian debt crises of the 1990s about whether the US should bail out the sinking currencies of these countries to prevent larger repercussions throughout the world's economies.  Moral hazard is the risk that those bailed out economies would not "learn their lesson" and the bailout would serve as encouragement to take similar risks in the future, repeating the crises and the need for future bailouts.  The concept of moral hazard resurfaced again during the recent economic crisis in the US, brought about by large US banks and their promiscuous lending practices.

Moral hazard and the decisions that it may influence have an inherent omission bias:  while I cannot force an alcoholic to take disulfuram (without a court order), the alcoholic cannot force me to provide him with alcohol.  The status quo is the moral reference frame.

Moral hazard stems from a fundamental underpinning of human behavior:  we learn appropriate avoidant behaviors through pain.  Children with a mutation that prevents them from feeling pain have short lifespans because they do not learn appropriate avoidant behaviors, as detailed in this poignant NYT article.  It is a striking article, and I don't think a person could have a full appreciation of moral hazard until they read it, so please do.

If there is moral hazard in general, it certainly exists in medicine as well.  I will illustrate this through several examples.

Should DNR be the Default Resuscitation Order After a Certain Age? The Case of Arnold Relman

"Oh lente, lente, currite noctis equi."  - Christopher Marlowe, The Damnation of Doctor Faustus

In at poignant and pithy piece in the New York Review of Books this year, the late Arnold Relman, former editor of the NEJM, described his experience breaking his neck and having cardiac arrest three times in the trauma resuscitation bay.  Because Relman was a visionary and outspoken pioneer in the movement to recognize and reduce medical waste and runaway spending (according to his recent obituary in the NYT) I thought it would be timely rather than disrespectful to evaluate the last year of his life after his accident as a case study on the utility of resuscitation in advanced age (I will not here attempt to define advanced age - only to posit that it exists at some cutoff that could be defined statically or dynamically).

No Code, Slow Code, 45 Minute (Purgatory) Code: Responsibility and Accountability in Attempted Resuscitation from Death

Physicians can abdicate their responsibilities as reasoned guides for patients making decisions at the end of life and as gatekeepers of resuscitation practices in many ways:

• By failing to address "Code Status" at all, letting patients be "Full Code" by default (and by failing to work as a profession to reconsider or change the default)
• By asking, in a matter-of-fact manner, "if your heart stops, do you want us to do CPR to try to restart it" without discussing the probability of success and the likely outcomes, both immediate and longer term, in the (often unlikely) event of success
• By failing to probe the reasons why a code status election that is at odds with their (and/or the nurses') judgment has been made; i.e., taking for granted the legitimacy of a Full Code declaration when doing CPR will clearly or likely be futile
• By discussing the issue of code status solely from an agnostic position, as though there is no right or wrong election, when in fact the physician has a strong belief about what is appropriate and what is not (such as Full Code nonagenarians, elderly patients with hemorrhagic stroke, those on the ventilator with multisystem organ failure, those with metastatic cancer, etc.)
• By defaulting to a Slow Code as a dissimulating compromise for the conflict between the documented code order and their sense of what is medically appropriate
• And the topic of this post:  by conducting a 45 minute code without reevaluating, during that time interval, the premises upon which the Code Blue was initiated, and without integrating the new information that accrues during the resuscitation attempt

Underperforming the Market: Why Researchers are Worse than Professional Stock Pickers and A Way Out

Here's an occasional cross post from the Medical Evidence Blog.  It's a bit more technical than what is usually posted on Status Iatrogenicus, but it gives a summary description of a pervasive problem with "evidence based medicine" that is so widely applicable to practice that I think it deserves some recognition here.

Underperforming the Market: Why Researchers are Worse than Professional Stock Pickers and A Way Out

Dated but Not Outdated: Why the Pager Endures as a Means of Physician Communication

In this post on the Huffington Post yesterday, Sachin Jain, a physician and presumably a technophile, bemoans the enduring use of pagers among physicians, labeling pager carriers as outdated and failing to leverage available technology to make communication more efficient.  As a devoted pager carrier, I will enumerate the many reasons why the pager is a preferred communication modality for many physicians, and the ways in which Dr. Jain is missing the point.

1. Patient Safety.  I work in the ICU.  If there is something that the RN needs to inform me, s/he needs to know that I have received the message.  If said RN (or intern or resident or other physician) pages me and I respond, they know I know.  If instead they send a text message or leave a voice mail, they do not know that I received the message.  They assume I did, and move on to other tasks.  If I did not receive the message, time sensitive things can get missed or delayed and that's a big safety issue.

Antifragile but Exposed: A Framework for Understanding Disease that Can Improve Diagnostic Decision Making

Ruination IPA by Stone

It is said that the history reveals the diagnosis 90% of the time, but it is not stated why this is so.  Herein I will explain the logic behind this aphorism.

I used to tell residents that most of the time, the diagnosis is something common, or something related to something we already know the patient has.  In addition, when teaching history taking, I told the medical students to view history taking as an exercise in determining what the patient is exposed to in his or her environment, for these exposures weigh on the probabilities of potential diagnoses.  These principles explain the basis of the history aphorism.

Nassem Nicholas Taleb was right in his book Antifragile - evolution has made our species beyond robust - antifragile, a term which he coined.  We resist disease, we repair injury, we get stronger when exposed to stress (the antifragile principle).  But there are ailments that humans suffer for which evolution has not worked out a defense or a solution, or those which result because evolution is helping the same organisms which attack us become antifragile just as it selects us for antifragility.  This is why infectious maladies are at the top of the list for adult (and I suspect pediatric) internal medicine admissions.  Pneumonia, UTI, URI, etc.

The Hits are Recorded, the Misses are Not: How the Culture of Medicine and the Third Party Payer System Foment Waste and Inefficiency

It doesn't make sense, but that's how we do it.  Usually, if you want to judge the calibration of a decision maker, you tally hits and misses both, not just the hits.  If you fail to record misses, a high hit rate might just signify a lot of swings.  But in medicine, we are taught to ignore misses.  It's only hits that count.  This doesn't make sense because it encourages overtesting and waste.  If surgeons practiced this way, all heck would break loose, everybody would be cut open and organs wantonly plucked from them.

There is a physician at a Midwestern institution who is known to come on service and order an echo bubble study on several (all?) patients the first day he is on service.  He has doubtless impressed a generation of medical students when the occasional PFO (patent foramen ovale) is found and he gets to wax prolific about shunts and other mechanisms of hypoxemia for a few minutes as they listen with fawning and rapt attention.  What they do not know is that he finds PFOs about 10% of the time he orders his echos, and this is just above the rate of PFOs in the general population.  He's basically finding PFOs at random.

No MOC for Me: Why I'm Not Signing Up For Maintenance of Certification

By the end of this month, holders of ABIM (American Board of Internal Medicine) and ABMS (American Board of Medical Specialties) board certifications are supposed to sign up for "Maintenance of Certification" a requirement that costs a bunch of fees and poses a bunch of busywork problems for physicians.  In general all I have heard in terms of reactions from colleagues are frustrated groans and begrudging acquiescence.  But I refuse to sign up for MOC.  Here are the reasons why.

Firstly, I am not required, for my employment, to have a board certification.  Nor am I for any other reason.  The only institution which can "force" you to have board certification is your employer or a hospital credentialing committee.  So, if somebody's gonna be the guinea pig, it may as well be me.

Jahi McMath: Poster Child for Medical Futility, or Scapegoat?

I periodically check for news updates on Jahi McMath, and today I found this news report that suggests that Jahi McMath is still alive, or at least that her heart is still beating, more than two months after she was declared dead on the basis of "brain death."

Based on the commentary on previous posts here and on PCCMcentral.org debating this issue, I can say the following:

1. Jahi McMath is legally dead on the basis of an incontrovertible and unequivocal diagnosis of brain death.  I have no doubts in this regard.
2. Jahi McMath has a beating heart and thus is not considered to be dead on the basis of the intuitions and opinions of her family and some others.

You may choose #1 or #2 above.  I personally don't care how you choose.  But I'm interested in the differences in reasoning and opinions among those who choose #1 and those who choose #2.

"No! Not NARCAN!" Exclaimed the Woman Not Breathing and Being Bagged

I will begin this post with a little anecdote.  It was about ten years ago at Johns Hopkins Hospital and I responded to a "Code Blue" on the step-down unit.  There was a woman, about 30 or 40 years old with several chronic medical problems who had stopped or nearly stopped breathing.  I was at the head of the bed delivering bag-mask ventilation (bagging; using the Ambu-bag, the first responder kinda thing).  We were preparing to intubate (insert a breathing tube into the trachea) the patient when an astute co-fellow, L.R., came on the scene and inquired as to whether the patient might be overdosed on narcotics.  He said aloud "should we try some Narcan?"  (Narcan counteracts the effects of narcotics and can cause arousal of a patient overdosed on them.)  This patient who was comatose, not breathing, and unresponsive in spite of being bagged and poked and prodded by the numerous staff who responded to the emergency, suddenly awakened and exclaimed, vehemently and audibly through the bag-mask ventilation:  "Nooooo!  Not NARCAN!"  Apparently, even a near-death experience is not as fearsome or worthy of arousal as reversal of the effects of narcotic medications.

Healthcare workers will find this amusing for its irony, and I could use it as a segue to a soapbox soliloquy about the dangers of narcotics, but I've already blogged that rant.  Here,  I'm simply using it as a segue to a discussion about the use of Narcan drips in the treatment of overdosed patients.  I was taught during a toxicology rotation in my residency a clinical saw that can be summed up as "If there's an antidote, give it."  Years of experience and reflection have borne out the wisdom of this adage.  Narcan and other antidotes are often benign and as I have discussed in other posts, their benefits even in uncertain cases often outweigh their potential harms enough that they should be given.  Narcan is especially useful when available to heroin addicts, when used by first responders in the field, or when used as a "test" of whether depressed consciousness is due to the effects of narcotics (as part of the "coma cocktail").  But when the decision has been made to admit a patient for observation after an overdose with prolonged effects, the question arises:  should we start a Narcan drip?

You Are the Hunted: Eat What You Kill Versus the Salary Model (Let Others Do the Killing, My Eats Are Free)

"It's hard to get a man to understand something when his salary depends upon his not understanding it."  - Upton Sinclair

This week, a popular NYT article describes how physicians are flocking to salaried positions in hospitals and healthcare systems in order to preserve their incomes amid reimbursement cuts, and to protect themselves against the vagaries and uncertainties of the healthcare landscape in the age of Obamacare.  For those not used to thinking about physician remuneration, I will give a brief synopsis.  There are basically two models of physician earning, and hybrids of the two.

The "Eat What You Kill" Model
Yes, this is the colloquialism commonly used to describe physician reimbursement in a pure private practice model.  An analogy to hunting for survival, you get to bill for, and keep the collections from, patient encounters that you pursue.  The harder and the more often you hunt, the greater your bounty.  Here are the problems with this model:

Behind Closed Doors Lurk Proxy Wars: Is Visitation Really About Visitation?

I decided to rewrite this today, on January 30th, 2016, after thinking about it for almost two years.

The previous post took on the heretical task of making the case against wide open visitation in the ICU without restrictions.  I took that stance for several reasons.  First, I'm a heretic and an iconoclast, and I believe that free thinking, rationality, and good judgment and decision making require all angles of a debate to receive their due - my goal is to keep the dialogue fire stoked.  Related to this, I sensed (and still sense) an agenda - open visitation is being pushed for ideological or financial reasons (yes, the almighty dollar - patient satisfaction scores are tied to Medicare reimbursement), professional associations such as the AACN are pushing the issue, and substandard data are being touted to support this agenda.  Next, it was and is my belief that because of the agenda, nurses' (and physicians') dissenting voices are being shamed into a collective hush by The Man, as it were, and that this censorship needed redress on this blog (it got redressed in 60,000 views and over 100 comments to the original post, still visible below.)  Furthermore, this institutionalized censorship may cause pervasive Hawthorne effects in any nursing survey that is done on the topic.  Finally, it was and is my view that if open visitation is the stated goal, there may be subgoals that are driving the desire for open visitation, and satisfaction of these subgoals through other means may be superior to open visitation for making everybody happy.  That is, desire for unrestricted visitation may be the symptom of an underlying disease and treating the underlying cause (such as poor communication) may cure both the disease and its symptoms.

Even if these considerations are cogent, reasonable and rational (which does not mean that they lead to the correct conclusions), there was a significant omission from my train of thought, small hints of which were peeking through from the text.  If some physicians and nurses don't want open visitation, maybe that too is the symptom of a deeper underlying disease that likewise could be addressed in other specific ways - and it thus follows that restricted visitation is not necessarily the solution that their symptoms demand either.

Doctorin' with Double Effect: The Ethics of Withdrawal of Life Support and Oxygen in Dying Patients

There has been a lot of discussion about the ethical nuances of withdrawal of life support and provision of medications that relieve suffering but accelerate death, but precious little about an important aspect of end of life care that comes up all the time - what are our obligations regarding provision of oxygen to dying patients?

The withdrawal of life support is an activity (a commission) that is ethically protected because patients' autonomy and right to refuse treatments overrides the harm (death) that comes about when physicians act to withdraw life support.  This in itself is interesting because most states prohibit euthanasia (or the provision of prescriptions that enable patients to take their own lives), which is in essence a commission (as opposed to an omission) that accelerates death.  I'm struggling to understand the distinction, except that the withdrawal of life support restores the patient to a "natural state" and allows nature to take its course, whereas the provision of a prescription to allow a patient to overdose is a commission that seems to interfere with nature.  (Jonathan Baron has written extensively about our preference for "natural states" which often leads to worse outcomes.)  That takes care of the natural versus human distinction (which of course ignores that humans are part of nature), but I still struggle to understand why the patient in Oregon has to administer his own overdose, unassisted by a healthcare professional - what's the difference between a healthcare professional assisting with the administration of an overdose and accelerating death, and his removing life support and thus accelerating death, if both acts are in deference to patient autonomy, and both are commissions, and indeed both are direct actions, as opposed to indirect ones?  Maybe it's because you can act directly and cause harm in respect of autonomy as long as you restore a natural state (withdrawal of life support), but you cannot act directly to cause harm in respect of autonomy by causing an unnatural state (medication overdose).  I think this stream of consciousness has led me to the distinction.  Maybe.  The devil is in the details.

The Girl is Brain Dead but the Emperor Has No Clothes

Oh, my, what a predicament.  Jahi McMath has been released from Oakland Hospital to the custody of the coroner and her family.  She has been issued a death certificate.  And she's being transferred to an undisclosed care center, where it is hoped she will begin receiving artificial nutrition.  This is the height of both irony and tragedy.

The comments by physicians and bioethicists in the CNN articles all harken to the idea that there appears to be no error, she meets criteria for brain death and thus she's "legally dead."  This misses the point.  Her parents don't care if she's "legally dead."  The legal definition does not comport with their own intuitions about death and her mother says as much.  She will accept that her daughter is dead only when her heart stops beating.  I can understand why a person may take this stance.

Real (Cardiac) Death and Invented (Brain) Death: The Oakland Case

This article in the January 4th, 2014 New York Times reports on the tragic case (the "Oakland Case") of a 13-year-old girl who suffered complications from elective surgery in early December 2013, whose condition deteriorated and who has been declared brain dead.  While it is not articulated directly in the article, her parents appear to object to the medico-legal conceptualization of brain death and they wish to force the hospital to continue to provide care for her.  A judge has placed an injunction against the hospital, prohibiting them from removing her from life support (in this case, this most likely means mechanical ventilation) until Tuesday January 8th, 2014. The medical establishment at the hospital where she is/was a patient has clearly taken the path of defending the concept of brain death and their rights and responsibilities under the laws concerning brain death -they have refused to insert a tracheostomy or a permanent feeding tube into the girl - and they may have, and we may be tempted to, ascribe her parents' behavior to anger, grief, bereavement, etc.  But I think this case illuminates some broader issues about bioethics, brain death, and organ procurement.

For those unfamiliar with the medico-legal definitions, brain death is a diagnosis that is made after severe brain damage from a variety of insults.  It is a very specific diagnosis that is based on a host of physical examination techniques and sometimes corroborating diagnostic studies, and it means that there is evidence of irreversible cessation of ALL brain function that has been caused by total lack of blood flow to the brain.  A patient who is declared brain dead is legally dead.  I have diagnosed brain death dozens of times.  The medical mantra is that, properly diagnosed brain death always means that there is NO brain function and that "real death" (that is, cessation of heartbeat) will inevitably ensue in coming weeks or months as the body cannot continue to  function without brain function.  But isn't this interesting!  That we need to reassure people that "real death" will inevitably ensue seems to reveal that we recognize that brain death is not real death, but that it will, after time lead to real death!  (Of course, all paths lead to real death, eventually.). Clearly this landscape is fertile ground for cognitive dissonance.  Let's explore why.

In Praise of Lasix: A Utility Approach to Pharmacotherapeutics

In a prior post, I focused on reducing polypharmacy to oligopharmacy or nopharmacy because of an underlying belief that most medications are useless at best, harmful or wasteful or distracting at worst.  But I'm not a complete nihilist.  I've also done a good deal of thinking about some medications that I think we should use more of.  On the basis of Bayesian and therapeutic threshold approaches to decision making, it stands to reason that one should have a lower threshold for using high utility/efficacy agents.  The utility of a given agent is the product of the probability that a disease it treats is present and the utility of the agent for that disease (which is itself the probability of an effect in any case and the magnitude of that effect.)  Thus, if the utility of the agent is high (furosemide/Lasix), it could be useful even if the probability of disease is low (CHF in a patient with normal BNP and ECHO); indeed it could have more net utility than a low utility agent (Digoxin) in a high probability disease (EF 30%, BNP 1000). Note also that if the agent is effective at treating a common disease (as opposed to a rare one), it's general utility will be higher. It follows that the threshold for the use of these high utility agents (when I say high utility I mean net utility, thus the benefits greatly outweigh any side effects) should be low - and we should actively look for opportunities to use them.  Here are the drug utility equations (where Drug X treats Disease X):

General Utility (drug X) ~ Prevalence of Disease X * (Probability of effect in Disease X * Magnitude of Effect)

Specific Utility (drug X) == Probability of Disease X * (Probability of effect in Disease X * Magnitude of Effect)

So, in sum, drugs have higher utility when they treat common diseases, and when their effects on disease are both likely and of high magnitude.  Lasix fits this bill because fluid overload states are common, Lasix makes almost everybody pee (if given in adequate doses) and it makes them pee a lot (if given in adequate doses.)

Your Last Words for a Few More Breaths: Unspoken Trade-offs in End-of-Life Care

A man with widely metastatic cancer is admitted to the hospital for shortness of breath, deteriorates in spite of broad spectrum care, and is transferred to the ICU.  The patient is documented to be "full code" and, while the prospect of "coding" him is unsettling for his providers, they struggle to articulate exactly why.  (Correct intuitions are often difficult to dissect and describe.)  Often the discussion (amongst themselves or with the family) centers on the direct, observable, physical aspects of suffering that must be borne by the patient during the resuscitation process and/or the transition to life support.  "Breaking of ribs" and the like.

But years of quiet and thoughtful reflection identifies some second order and often unspoken nuances of the transition to life support that are perhaps more important than the first order physical aspects.  When the man dying of cancer deteriorates to the point that his oxygen saturation cannot be supported without life support or his respiratory distress is too severe, and I position myself behind that bed, propofol and an 8.0 (endotracheal tube) in hands, I know the oft unspoken truth - that this is the last time that this man will be indubitably conscious and coherent or will speak to anyone, most notably his family.  Insomuch as life consists of an interaction with one's environment, with a central focus on social interactions, the patient dies the moment I induce with propofol and insert that tube between the vocal cords.  He has traded his last words for a few more breaths.  (He has also traded away his ability to enjoy food or drink.)