Volume responsiveness and volume tolerance: a conceptual diagram. #FOAMed, #FOAMcc, #FOAMus

So I know I’ve belaboured the point about the difference between volume responsiveness (i.e. will there be significant increase in cardiac output with volume infusion) and volume tolerance (is the volume I am considering giving going to have nefarious consequences), because in my opinion, the focus has been – rightly so to some degree – to look for an accurate way of discerning responsive patients from non. Of course this is absolutely necessary, as one does not want to give volume if it will not have any benefit, but the too-common corollary to that is to automatically give volume to those who are responsive.  Here is an earlier post about this:

Fluid Responsiveness: Getting the right answer to the wrong question. #FOAMed, #FOAMcc, #FOAMus

So in discussing with a bright young colleague yesterday, Dr. St-Arnaud (@phil_star_sail), I realized that there may be a common conception that physiologically, the relationship between the two may be the following:

Screen Shot 2016-02-21 at 9.03.01 AM

This would mean that it is safe to give volume until a patient is no longer volume responsive, and even perhaps a bit more. Alternately, the two may be closer:

Screen Shot 2016-02-21 at 9.02.27 AM

This would mean that once can go just till the point where the patient is no longer volume responsive.

Either one of these scenarios would be awesome. That would mean that by using any of the flow or volume variation techniques, arterial or venous, we could pretty much remain safe.

However…

While the above may hold true for healthy subjects, I would contend that in sick people (which is who I tend to deal with, especially when resuscitating shock), that the more likely physiological relationship is the following:

Screen Shot 2016-02-21 at 9.03.28 AM

Hmmm… That would mean that assessing for volume responsiveness would only tell you that there would be an increase in cardiac output, but absolutely nothing about whether it would be safe to do so.

This concept is not a new one by any stretch of the imagination. It’s inferred in the diagnosis of “non-cardiogenic pulmonary oedema.” So what causes this shift? Here:

Screen Shot 2016-02-21 at 9.25.50 AM

So, how do we figure out where the point is? Sorry to say there is no answer that I know of. My friend Daniel Lichtenstein uses the FALLS Protocol (identifying the appearance of B lines during resuscitation) which is the least we should do, but I suspect that at that point, we have already overshot the mark. My adopted mentor Dr. Andre Denault (@Ad12andre, in addition to IVC, has identified portal vein characteristics including pulsatility (lots of stuff in press) to show that the viscera are at risk, but as of yet there is no simple answer. CVP value? Please. CVP tracing morphology? Maybe.

No simple answer. No one-size-fits-all velue to look for. Clinical integration.

In my opinion, one should not, in sick patients, seek to volume resuscitate until the point of no-volume-responsiveness. The old adage of “you have to swell to get well” likely kills a few additional patients along the way, just as much as under-resuscitation. I plead guilty for over-resuscitating patients for years before realizing that being on the flat part of Frank-Starling is 100% a pathological state.

Love to hear your ideas and comments!

 

Jon-Emile Kenny says:

I like your graphics, it makes the concepts tangible. I think we should try to integrate ‘volume status’ into this framework as well. A physiological purist might say that as soon as you are ‘hypervolemic’, you are volume intolerant, because hypervolemia is an abnormal state which should always be avoided. A functionalist might say that you become volume intolerant as soon as you have physiological embarrassment of any organ system – but how is this determined? My gut is that by the time there are B-lines in the lung, you’ve gone too far. By the time there is abnormality of splanchnic venous return, you’ve already gone too far. I am more of a purist, so in my perfect ICU, I would perform q4-6 hour radio-labeled albumin studies to determine the patient’s true plasma volume. In health, the normal blood volume is about 80 mL/kg [thus, once you’ve given a 70kg man 5 L of NS, you’ve almost certainly replenished his vascular volume]. The moment that the blood volume becomes > 95% the norm, I would call the patient volume intolerant and stop volume expansion and focus on venous tone with pressors, cardiac function with inotropes, etc. To me, this makes the most sense in the pure Guytonian world; if you keep flogging a patient with litre after litre of fluid and the patient’s BP remains low, you are missing something – volume is not the answer – regardless of what an ultrasound shows you:
1. trouble shoot the venous return curve [i.e. too little blood volume, too little venous tone, too high resistance to venous return]
2. trouble shoot the cardiac function [i.e. poor rate, rhythm, contractility, valve function, biventricular afterload]
If you need some objective measure of blood volume before you can call volume status optimized before moving onto the next problem to fix – that’s a radio-labeled albumin.
Maybe I’m crazy.cheers

Jon

Thanks for commenting Jon!

I totally agree, if we knew each patient’s normal blood volume, that would be a starting point.  And of course, that would prevent the over resuscitation of a very dilated and compliant venous system (small IVC on ultrasound). Let us know if you figure out a practical way to do that!

It’s too bad that extravascular lung water doesn’t seem to have panned out – not sure why exactly.

 

 

Philippe

Resuscitation Leadership Academy: Check it out!

 

Screen Shot 2015-09-18 at 11.05.26 AM

Screen Shot 2015-09-18 at 11.05.11 AM

Just wanted to invite everyone to take a look at the Resuscitation Leadership Academy (www.resuscitationleadership academy), brainchild of Haney Mallemat (@criticalcarenow) and Scott Weingart (@emcrit), neither of whom need an intro at this point, needless to say.  Much thanks to them for inviting me to the faculty, very honoured to be a part of the team!

Basically the RLA offers an online curriculum packed with great material, but more importantly the opportunity to do an online hangout with any faculty member and discuss cases, topics, etc, in an informal but very informative manner. I think this is a great resource for trainees as well as those who are in practice but either lack an academic environment or really just want to tap into some of these guys’ experience and knowledge.

Looking forward to meeting some of you in a hangout!

cheers

Philippe

Musings with Jon-Emile and Philippe 4: A Podcast on Pointers, Pearls and Opinions on Tough Ventilation Cases. #FOAMcc, #FOAMed

Hi, so in this little discussion, we go over some points about ventilating ARDS, obese patients, looking for optimal PEEP and other obscure physiological point that we are somehow interested in…

 

Love to hear comments and questions!

 

 

cheers

 

 

Philippe

Bedside Ultrasound-Assisted Procedure: Hepatic abcess drainage. #FOAMed, #FOAMcc

Hi,

Apologies for a long hiatus. Thought I’d share a case from last night. A 54 year old man had been admitted with e.coli sepsis complicated by portal vein thrombosis and multiple hepatic lesions a few weeks ago. A follow up scan by the hospitalist showed the following:

Yup, nasty. So our ICU Outreach service was called (we do all manners of procedures on the wards/er) and it happened to be me.

So 10pm I make my way with all the necessary gear (not much you can’t get done with ultrasound and caffeine!):

IMG_4242

Here is the clip:

So this is a synthesis of several US loops. The first ones simply show the lesion, which under US is clearly fluid – movement well seen with respiration/pulsation. Next you see the associated ascites and a quick peek at a subxiphoid view of the heart.

You then see the procedure itself, with a needle insertion (purposely jerky for visualization’s sake), and, following a 3 way stopcock connection, gradual drainage of the abcess.

IMG_4246

I chose to hand-drain it in this case to avoid possible blockage of the tube if simply left, since it was a small 8.5 french pigtail catheter (better for comfort). You can see that the access cavity was essentially obliterated. 400 ml or so drained:

IMG_4247

So technically this was very simple, however the one important teaching point is to pick an inferio-lateral approach, as an easier but more treacherous one – simple lateral – might result in going thru the pleural space because of the lateral costodiaphragmatic recess which extends quite inferiorly. So when picking the entry point, it is important to make sure it is below the diaphragmatic insertion. Otherwise the potential to seed the pleural space with abcess content is there. This would be sub-optimal.

The advantage of bedside ultrasound? Quick and easy drainage during the weekend when interventional radiology isn’t readily available.

cheers!

Philippe

Lung Ultrasound Day for Internists 2015: ASMIQ/CCUS, Montreal, May 29th 2015.

In collaboration with the Quebec Association of Internal Medicine Specialists (ASMIQ), and featuring none other than Dr. Daniel Lichtenstein (the original pioneer of bedside ultrasound and the first to truly do and develop lung ultrasound), we’ve put together a really good day of lectures and workshops. As a bonus, my good friend Dr. Haney Mallemat (@criticalcarenow) will be giving us a hand with workshops and maybe even a special lecture! Take a look:

ASMIQ 2015 Lung US Program

This takes place in Montreal, at Santa Cabrini Hospital, and places are limited, so anyone interested should register promptly at http://www.asmiq.org.

Do note that most lectures will be in french!

thanks,

 

Philippe

Musings with Jon-Emile & Philippe 2: Putting Jon on the Spot!!! #FOAMed, #FOAMcc, #FOAMer

So in this second instalment, I put Jon-Emile on the spot about some common clinical scenarios which, to me, contain a bit of dogma. Let’s see if physiology will give us the bottom line!

 

I think these are actually really important, because just too many times, I hear people automatically saying that in RV infarct, the patients need a lot of fluids, and in PE and tamponade as well.  I’m not so sure that’s always true, so I thought it would be a good idea to review this physiology with s real pro!

 

enjoy, and love to hear some comments!

 

cheers

 

Philippe

 

Bedside Ultrasound Case: Look Left and Right! #FOAMed, #FOAMus

So I get a patient in the ED who had chest pain and a decreased LOC, vomited and got intubated. I see this elderly (88 yrs old) gentleman a couple of hours after presentation, after basic management including some plavix and heparin for a mildly elevated troponin.

Of course, by now you all realize that a rapid CUSE (Critical UltraSound Examination) is what I start with, after an ultrabasic history.

So my first couple of views show a more-or-less normal IVC, and here is the parasternal long axis:

Anything exciting here? Not really, nothing to hang your hat on at a glance.

Ok, so thanks to FOAM, I recently decided to add the right parasternal view to my regular exam, both to look for lung sliding (I admit I sometimes skip this when not specifically looking for pneumothorax) but also to possibly see some right sided pericardial abnormalities, etc… Here is what I see:

Hmm… A large, vascular structure that seems to have two lumens… a flap? Back to the patient exam, and the left toe is upgoing  and seems more flaccid in the left upper extremity…

Lets creep up the vascular path to the neck vessels:

Here, we can clearly see that most of the carotid lumen (lower right) doesn’t have any flow. That’s suboptimal. In fact, only a small crescent of flow between 3 and 6 o’clock is seen.

Here is the CT:

 

So here we can clearly see the dissected ascending aortic aneurysm that extends into the right carotid artery.

Due to advanced age and dismal overall prognosis, support was discontinued after discussion with the family.

I thought this would be a great case to share due to the fact that it could have been an initial bedside diagnosis, but I have to say I consider it fortuitous that I happened to look right, then up – which I easily could not have done. Not that it made any difference in this case, but on the next one, it just might!

 

Thanks FOAM!

 

cheers

 

Philippe

 

 

The Great Septic Debate: Science vs Science (Part 1), by Dr. Lawrence Lynn and Dr. Steven Q. Simpson, #FOAMed, #FOAMcc

So after I put up Lawrence’s comment as a standalone post, a rapid-fire exchange began between him and Dr. Steven Q. Simpson, who is another one of these really bright guys I’ve had the pleasure of interacting with on the FOAMsphere.  I thoroughly enjoyed their debate and most definitely think there is a lot to gain from listening to both of their points of view. So if anyone missed it, go back to my last post a few days ago and catch Lawrence’s opening punch, and without further a due,  here is Steven’s counter:

These arguments are well intentioned, but they are, in my opinion, off the mark on a couple of levels.

First, the “N of 1” notion. If this were REALLY true, then we could toss out the collective knowledge of patient care that we have garnered through a lifetime of our own experience, not to mention the experience of others. Why would I use antibiotics in THIS infected patient if the experience of “most” patients is of no use to me or my patient? You may protest that this isn’t what was meant by the proposition. The collective experience of “most” patients with antibiotics seems too obvious for us to ignore. And the notion is too compelling – if you can kill bacteria in “most” patients, why not in this one?

Yes, this feels to you as a reductio ad absurdum argument. But I say this – if the “N of 1” argument has legs, then it should stand up across the board, for all clinical circumstances – or, at least for most. I can easily dream up an infinite number of clinical circumstances where this “each patient is an individual and will behave differently from most patients” argument falls down. So can you. Frankly, the entire argument isn’t even actually trying to achieve N=1. Do you not seek to define a phenotype, so that those with that phenotype will be treated in one way or another? Everyone? Or only some? Why define a phenotype, unless those who have it can be expected to behave in one way or another with some form of treatment? Why have the biological sciences at all, if we cannot from them derive some truths that are universal?

We will use antibiotics in this patient precisely because science tells us that a combination of them is highly likely to kill some combination of bacteria, and because the collective experience of the literature, our teachers, and ourselves tells us that this patient stands a high likelihood of responding like “most” patients. In truth, I typically see the “N of 1” argument trotted out when the arguer simply doesn’t like the opposing argument, which is illustrated by your post. In this case, the opposing argument is that the currently accepted definition of sepsis has substantive meaning, and that it is something more than a guess.

Ok, gotta chime in. The N=1 is, to me, undeniable and cannot be circumvented. Although I understand the necessity for trials, the data cannot be blindly extrapolated to all patients, but rather should represent a step forward, a proof of concept perhaps, another little brick in our understanding. The issue is just at which level one is looking. I fail to see how one has to throw away any accumulated knowledge – if anything some of that knowledge should point to N=1 cases rather than away from it.  How can we on one hand acknowledge the vast variation of organ functions, system responses, etc, and imagine that one shoe could fit all in the best possible fashion?  Antibiotics? No argument at that level, but the N=1 may apply at the level of the dose. We routinely give the same dose to a range of patients, some of which we weight base, some we base on creatinine, but a fair bit of evidence has come around recently to suggest that, paticularly in young and (previously) healthy patients, they may have increased clearance in certain phases of sepsis and that if we were to look at serum levels, we are actually under-dosing.  Serum level-based dosing is coming. But ceftriaxone 1g q24h for everyone may not be best for all, even if it is best for most, and waayy better than no ceftriaxone at all. A great lecture by Jeff Lipman on ICN can be found here:  http://intensivecarenetwork.com/pharmacokinetics-critically-ill/

The author who calls our working definitions of sepsis, severe sepsis, and septic shock a “guess” simply does not have a long enough memory. I, myself, have vivid memories of the patient who set my career on a whole different path, the patient for whom I first asked myself, “Does this man have sepsis?” It was October of my internship, 1983, and I was called to the CCU to evaluate a man who was febrile, tachycardic, tachypneic, and with altered mental status. It was the CCU, so I first checked physical exam, EKG, and cardiac enzymes. Nothing. I called my supervising resident to come, and I asked him, “Do you think this is sepsis?” To which he replied, “I don’t know, maybe, what makes you say that?” I didn’t have a real answer, but it didn’t take long in the library for me to figure out that no one else did, either. The best definitions of the time suggested a need for demonstrated bacteremia. That seemed a bit wrong to me, because it seemed silly to wait for 24 hours or more to prove that before initiating treatment. Luckily for me, it also seemed wrong to a man who had previously been an assistant professor at my own institution (the University of Kansas), Roger Bone. It seems that, beginning in the late 1970’s, while working at KU, he had proposed a syndromic definition of the condition and had set about determining whether his definition had some validity. In 1983 he had not published that, yet. But, by the time I was his fellow at Rush he had evaluated his definitions, risk-stratified patients according to them, and used them to study therapeutic strategies. It was on the basis of his investigations that the critical care community found our current working definitions to be preferable to older definitions and published them in 1992.

“Not enough”, you may say. Roger would agree with you, and so do I. Even in the late 1980’s he was looking for better ways to characterize patients with severe sepsis, and so were those of us who worked with him. The initial segment of my academic career was spent in characterizing the TNF response to gram negative and gram positive bacteria and in determining whether patients’ responses could be phenotyped on that basis. Were he alive now, Roger would applaud any and all attempts to better stratify on his definitions, or even to replace them. As long as the replacements are characterized, tested, and demonstrated to have meaning and efficacy. Until now, there are few phenotypes characterized, and none has jumped the hurdles of prospective efficacy testing. Many involve laboratory testing that is simply not available to the average intensivist. Ideas abound, and attempts to test them abound. Your post sounds as if there are no attempts being made to replace what we have, but the attempts are there. They just haven’t jumped all the hurdles, yet. I agree, though, we must keep trying.

I want to take a moment to mock myself. One of the reasons I deplored rheumatology as a specialty during my residency was the absolute reliance on syndromic definitions. But it wasn’t just that. It seems that a rheumatologist can just set aside whatever portion of the definition that he or she doesn’t like. ANA negative lupus? What are you talking about? Either it is or it isn’t caused by antibodies to DNA, right? Or, if the syndrome “overlaps” we have mixed connective tissue disease. Yes, they have made some progress through the years. We know that this or that antibody is “more likely” to be associated with this or that disease. Or this or that gene mutation. But we are rather mushy all around in our definitions of diseases as syndromes. Sound at all familiar? It is beyond me why it drives me crazy in rheumatology, but in critical care I have some equanimity about it. Perhaps it is because it all plays out much faster in the ICU. I don’t know.

Meanwhile, if you think that where we are with diagnosing severe sepsis now is a guess, then you have not been out of your ivory tower in awhile. I have spent the better part of the last decade attempting to teach people in hospitals across the nation, but especially in my own state, that these definitions have some meaning. Teaching them that one does not have to wait until shock is present to get aggressive. Coercing them to collect data on whether they are recognizing, whether they are treating, whether they are effecting better outcomes. I can assure you that the data collected show this: without organized efforts they do not recognize, nor treat aggressively, while with organized efforts they recognize better, treat better, and save more lives. In my own institution, the mortality rate for severe sepsis, which sat at 49% in 2004, was down to 9% in 2014. With effort, with constant training, and with vigilance. All while using the SAME “guess” at diagnosis. Meanwhile, it remains a hard sell to hospitals across the nation. Do not believe for an instant that what you know about sepsis translates to the average hospital in this nation or this continent. Yet, they grasp at every argument made by academic skeptics who rail against the “confines of a bad definition” and “the limits placed on us by protocols” to illustrate why they don’t need any particular efforts in their own locale.

The people who will achieve recognition at the upcoming SCCM meeting have understood something that is missing from the arguments in your blog post – that the perfect is the enemy of the good. Had they pitched in trying to find a perfect phenotype to attack, they may have been successful by now. I doubt it, because they have, in fact, continued the search for better phenotypes, along with their current treatment endeavors. But even if they had found the perfect phenotype after all these years, they would have left tens, if not hundreds of thousands of patients dying. Since we are, after all, in the business of saving lives, we must not allow the search for the perfect phenotype to be at odds with our best possible use of what we currently know. What if the American people had said to Henry Ford, “We don’t want your stupid black Tin Lizzy. When you’ve got air conditioning, quadrophonic sound, heated seats, rear cameras, adjustable wipers – hell, when you’ve got a car that will drive itself – then come back and talk to us. We don’t want anything, until we’ve got everything”? What would we be driving now? Horses? Who knows? Our current diagnostic criteria and therapeutic approaches may be Tin Lizzies, but they are helping to save lives far better than the previous horses. And, by the way, the ideas promoted by these people are only just now seeping into the establishment. It is actually the establishment that has resisted most the idea that we should make hay with what we have, rather than watching septic people die while we work on finding just the right phenotype.

Ok, gotta give a thumbs up for Steven here, I think this is a great point. The quest for perfection, in science as much as in life, is an antidote for happiness, or good, in most cases, and that those things which are discovered along the way which are good should not be discarded because they are not perfect.  They should represent something to use until something better comes along, and often we may need that footing to get to the next level. There is in my mind absolutely no doubt that EGDT and the Surviving Sepsis Campaign has saved lives, both by detection/awareness and by promoting some therapy and vigilance. This is a massive accomplishment, period.

Another stop for self mockery. I’d be wealthy man if I had a nickel for every time someone heard me say, “If we’d spent the billions of dollars that have been used to set up an organ procurement system and improving allograft transplants on actually developing artificial organs, we’d have had them by now, and all of this other stuff would go by the wayside.” I guess we all have our axes to grind, eh?

We all dream of a day when a stat test can give us the phenotype/genotype information to individually tailor our treatment. Many people, including myself, are constantly evaluating how to get us there. But it serves no purpose to denigrate the activities of the realists, also including myself, who take the very best info we currently have and attempt every day to make the very most of it.

Steven Q Simpson.

Well, it didn’t stop there: Lawrence replies…

You make many excellent points in your courageous defense of present sepsis science. No one else has the courage to defend it. I respect much of what you have said and no one can argue that the SSC and individuals like you have made a important difference. Those of you who have dedicated your lives to improving sepsis awareness warrant tremendous respect.

However, it is clear you misunderstand. We are not critical of the sepsis awareness efforts, nor do we doubt that this has had a positive impact.. This is about science, not paternal expediency. Perhaps it was expedient in the past to control the science but now it is time to do real science, studying real “true states”, and generating real statistics.

Our problem is not with SSC public health efforts, we applaud them. Our problem is with confusing the simple guesses of the 1980s for the “true state” of sepsis and septic shock and applying statistics and drawing broad conclusions about “sepsis” when the results really only relate to a group defined by the guess and not a specific clinical condition.. That is pathologic science which has not, and will not, render reproducible results.

You say the sepsis criteria were derived from data? Where is that published? Was a band count of 10, a HR of 100-10, and a SBP of 100-10 and a RR of 2 times 10 derived from data? The first step to reform of sepsis science is to present the data so we can examine its validity or to admit, in open forum, that they were guessed.

This is also about transparency of clinical trails. In the discussion section of any trial, the important limitations of the trial should be identified. Yet, in not a single sepsis trial in 25 years was the limitation of using guessed criteria (or simple static thresholds for a dynamic relational condition) as the “true state” mentioned. Nor was it mentioned that a different set of guessed criteria might have rendered different results for the trial. Whether that ubiquitous omission, which pervades the entire standard science of sepsis, is due to expediency or because the researchers have fooled themselves into believing their own guesses were gold standards is impossible to tell.

We also fool students when we give too much decision weight to static thresholds and this can cause harm. A patient with a WBC of 11, 9% bands, and a platelet count of 120 may be profoundly ill. with advanced sepsis. Static thresholds can provide a false sense of security. When such data fragments are promulgated from a central authority to ne trusted and relied upon for critical decision making and applied without an understanding of the physiology and the dynamic relational patterns of unexpected death, this may harm as many patients as are helped.

This is discussed in http://www.ncbi.nlm.nih.gov/pubmed/21314935
This article shows how well meaning, paternal oversimplification can be a pitfall.

Here is a solution:

First: SCCM needs a formal declaration of Glasnost. Allow scientist to openly call for reform of sepsis science without begin labeled as “academic skeptics” for not promulgating the failing dogma. Why do you think everyone stays silent, the young academics cannot risk being called an “academic skeptic” by the thought leaders. You make my point when you attempt to bring that hammer down on me in the end of your argument..

It is ironic to be called an “academic skeptic” by those who, argue for “science” as a function of paternal and utilitarian pragmatism . Using guesses as the true state because it is perceived as pragmatic is not academic, its pathologic science (as described by Langmuir) and generally occurs because good scientists have fooled themselves or are acting under social forces and political expediency..

Here I have to speak to all the young readers. Do not be afraid to be called an academic skeptic or “denier”.. Do not be afraid to speak out against dogma. Popper identifies volitional falsification as a manifestation of a true scientist and so it is. However, Kuhn points out that thought leaders will not abandon their dogma despite falsification.. He points out that that is where Popper’s idealized concept (of science as progressing though events of falsification) fails. Thought leaders will ignore results which falsify their own dogma (even on the 25th anniversary of the failed dogma).

As a matter of fact, be afraid of accomplishing nothing if you are not willing to take risk and speak up and challenge your mentors at the most fundamental level. If he or she does not like that, find a new mentor. Remember that when the dogma fails, and a the scientific paradigm shifts, the thought leaders will scurry to the new paradigm with the same zeal which they employed to protect the old one.

Second: Continue the sepsis awareness process . (Do not worry, Glasnost will not derail those efforts.) Provide awareness along with more advanced education about the dynamic relational patterns of the lab and vitals in sepsis (Teach nurses the type I pattern of death rather than placing reliance on a WBC of 12). For example we should teach that the WBC often falls to normal in sepsis after it rises and that while WBC is useful, reliance on any WBC or band threshold is a pitfall.

Third: Determine the phenotypes of sepsis with a large clinical trail which collects all the data. What are the different dynamic relational patterns of sepsis. These are the signatures of the different phenotypes of sepsis. The sub sets of the patterns of sepsis death.

This, to me, is huge. This is the era of big data, and we need to have huge amounts of it to pore through and begin to see patterns and associations that were not necessarily (and arbitrarily) pre-determined.  One of these, for instance, that (due to the difficulty in obtaining the data) is never taken into account is the phase of sepsis. No patient presents at Time 0.  They have all waited a variable amount of time, and their individual rate of progression through the stages likely varies. Hence, treatment may vary also. Degree of capillary leak? This in turn may depend on the particular pattern of an individual (eg IL’s and TNF etc) to a particular bacteria. We do not all react the same way to antigens do we?  I don’t have a problem with peanut butter or shellfish. Some people seem to. It’s all immune-mediated.  There are countless amounts of these possibilities which only big data will bring out. Back to you, Lawrence. 

I respect your response. None of the thought leaders dare enter the social media when their fundamental dogma is questioned. They stay where they can close discussion. However youhad the courage to read my article and publically challenge the premise. I am very thankful that there are courageous men and women like you out there passionate about saving lives and advancing science.

I would be happy to continue this discussion in open forum here. Bring reinforcements, the heavy hitters of the old guard. I am ready to be shown that I am wrong in public and that sepsis science does not need to be reformed. No more paternal control of thought.. Glasnost.

And to all the readers,… unless I am proven wrong, in one voice, call for glasnost and reform of sepsis science at the upcoming SCCM.

I don’t think the thought leaders will be doing any more defending. I’m still hoping they do.

To all the young scientists, I wanted to illustrate the objective, very real, and instant results of paternal control of sepsis science which goes beyond SVcO2 and protocols. See the ambitious study linked below. This type of research occurs when researchers rely on the fundamentals of the past (which they should be able to rely on) and no one is told (perhaps for paternal reasons as cited in the earlier comment) that the sepsis criteria were simply guessed. We have already indicated that the ARISE team was almost certainly not told that the standard sepsis “true state” for research was guessed and not derived from data.

Note this linked massive genome-wide study attempting to match the guessed unified phenotype of sepsis to actual SNPs. The genetic information is real but the unified sepsis phenotype is a guess so, of course, the findings are minimal.

This is why we cannot have a situation where we suppress dissent to produce a picture of solid science for the purpose of moving government and hospital administrators toward a well intentioned goal. This may seem like a good idea and may even be beneficial for a while. The problem is that many researchers do not get the memo. They don’t know sepsis science is paternally pathological. They think it is real (fundamentals based on solid data) so they waste time and dreams researching a “true state” which is not based in science. We cannot afford to waste research in the interest of maintaining the appearance of lack of dissent.

http://www.ncbi.nlm.nih.gov/pubmed/25533491

Most Respectfully

Lawrence Lynn

Well, that rebuttal was not to go unnoticed.  

A steadfast insistence that present sepsis science isn’t really science does not constitute an argument. I see from the hyperlink you include that you are definitely interested in genomic, possibly proteomic explanations for the syndrome. The particular article is, indeed, science, but in what way is it usable for patients? There is no scenario in which the information in it helps me to either diagnose a septic patient or treat them. Unless that science is pursued much, much farther. This reminds me of one of my favorite quotes: “We have not succeeded in answering all our problems. The answers we have found only serve to raise a whole set of new questions. In some ways we feel we are as confused as ever, but we believe we are confused on a higher level and about more important things.” That didn’t originate with sepsis, nor even with medicine, but a careful look will, I think, reveal that the thought applies. It also reminds me of where my own career in sepsis research began, investigating the role of TNF alpha in the pathophysiology of sepsis. The observations are still pertinent, but they have not helped me or anyone else to save lives. Observational associations will not help us, unless they are turned into real diagnostic tests or adequate targets for intervention.

I definitely agree with Steven here in terms of the need for practical application, and about the escalating confusion, but as physicians, we have to be comfortable with knowing that we are not practicing perfect medicine any more than our predecessors.  Better, but not perfect, and we have to accept this uncertainty as we slowly get more and more answers. Yet at the same time we are bound to do the best we can for our patients and keep a pragmatic, practical approach. Not easy.

I feel as if you are tilting at windmills when you attack the “old guard”, whoever that is. There is no such thing as paternal control of science, although I will grant you that the history of science is full of attempts at control. Science always wins. Along those lines, I am personally acquainted with the principals of the Surviving Sepsis Campaign and I know all of them to be encouraging of new science, not suppressive of it. The campaign, itself, has changed its recommendations based on new evidence. The members of the campaign are intellectually honest. Period. They would never suppress evidence, nor try to hold down good science. I am convinced that you are mistaken on that account.

Something else is troubling me about your argument. I don’t think anyone believes that the combination of infection, SIRS, and organ dysfunction is some sort of a complete descriptor of the state of sepsis. In reality it is, as Roger Bone described it, a syndrome that is recognizable to human beings who, as of yet, do not have x-ray vision or chemical sensors built in. So far, we don’t have even the tricorder. Roger recognized the syndrome not by guessing, but by careful observation of the patients he cared for (much like your observations about WBC). He did clinical studies to validate his observations and show that the syndrome was associated with a mortality consequence. It will, by the way, always be true that even when we have “the” stat lab test for sepsis, human beings in the form of physicians will need to recognize the need for sending it. And it will still be true that the sooner treatment is initiated, the more likely a patient will be to survive. Unless we develop the diagnostic tricorder, we are always going to need to initiate treatment based on data that we derive from physical examination.

The tricorder may not be as far away as we might think, Steven, there is data out there for early detection of sepsis using EKG data in kids (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2933427/), and the era of wearable tech is just beginning. 

All of that in no way negates your argument that more and better understanding of the pathophysiology of sepsis, its genomics, its proteomics, its epiphenomena is necessary and desirable. The steps you propose are the steps we need. So do it.

Now Lawrence did have a few more things to add…

We do not say the sepsis science is not “science”. We say that it is pathological science. Langmuir describes “pathologic science” as a science advanced by a group of often brilliant scientists who use the scientific method BUT make a fundamental mistake which they do not recognize. They are encouraged by threshold interactions which carries the enthusiasm forward with many papers often for decades. Eventually the “dramatic” results of earlier trials prove NON-REPRODUCIBLE. The number of disciples falls off and eventually the mistake is discovered and the science disappears. We are simply disclosing the mistake and explaining WHY the trials have failed. We are calling for transparency and are not attacking anyone.

Sepsis science is a classic example of Langmuir’s “pathologic science” . The sepsis criteria were considered the STANDARD for defining the “true state” in all sepsis research and this was the mistake in the scientific method which absolutely requires a VALIDATED “true state”. Even accepting your arguments that the sepsis criteria comprise an choice by someone brilliant like Rodger Bone, who we all respected, this does not change anything. Best guessing is best guessing no matter who does it. In Rodger’s days the “true state” of sepsis was thought to represent a “unified phenotype of sepsis” but we now know that a unified phenotype of sepsis may not even exist. All the large RCT trails using the unified phenotype as defined by the guessed “true state” have proven non-reproducible.

It is as if we are in the 1950s trying to figure how to treat “growths” on the body and we defined a expert guessed set of criteria for a unified phenotype of a growth or “neoplasm” and then treated all of neoplasm by the same protocol and had some initial encouraging results due to fortuitous patient mix and threshold interactions. In the end additional research using the unified phenotype would be non reproducible.

This is why the genomic wide investigation or any other investigation using an expert guess as the “true state” fails. I simply cited that genomic article to show why ALL research efforts based on pathologic science fail and how this is a waste perpetuated by lack of transparency.

We are working to define the actual phenotypes of sepsis. This education is simply to open minds.

It is said that failure to intubate the trachea occurs due to failure to recognize that one has not intubated the trachea. So it is that failure to recognize that sepsis science is pathologic prevent resources from moving the science from its failed position of generating non reproducible results.

I want to thank you for engaging in defense of sepsis science. This kind of dialog is what the young researchers need to see. If you do not think they are afraid, you are wrong. One young scientist recently told me that the old guard is just going to have to retire before the science can move on. They have careers, they know the politics of academia and… they are afraid.

If you desire to assure they will not be afraid, even if you do not call for reform, please join us and call for transparency. Let the limitations and origins of using simple threshold criteria for a complex dynamic relational condition be widely promulgated. I have confidence that once we set them free of the sepsis dogma and the grants can flow to fund a new direction for sepsis research, this new generation of young scientists will deliver the breakthroughs we have witnessed in so many other fields of science.

To further explain for the young docs who may think they can rely on thought leaders without examining the fundamentals for themselves:

A contemporary example of “pathologic science” was the science of peptic ulcer disease in the 1980s. This is before most readers time but Dr. Simpson will remember it well. Here brilliant scientists (almost all of them) “knew” that peptic ulcer disease comprised a single unified phenotype fundamentally caused by hydrogen ions. They performed massive research directed toward that perceived phenotype and at times, it worked. This went on for decades and seemed irrefutable given that in some settings excess hydrogen ion (e.g. Zollinger-Ellison syndrome) was the fundamental cause of peptic ulcers. They resisted the argument that there was another phenotype which was caused by bacteria. Eventually they could not hold. No one believes in the acid theory of peptic ulcer disease anymore but a zealous “acid theory denier” could find him or herself quite lonely and isolated in academia the early 1980s. This is what Dr. Kuhn says WILL happen and not even Dr. Kuhn knew how to prevent it.

The thought leaders don’t have to reform sepsis science, they just have to formally promulgate that just maybe it should be FUNDAMENTALLY reformed. However this must be described by the leaders as a potential fundamental reform not a new consensus for a new set of thresholds. Then the gates will open for the young docs with fresh ideas.

The thought leaders have accomplished so much and have saved so many lives. That legacy will not be lost. There is no downside. Join us, and call for reform or at least suggest that formal consideration fundamental might be a good idea.

Now after reading this, if you reread the linked article below, you will see that it is not an attack on thought leaders but rather it is simple a story of good science on its normal path full of deviations on its way toward truth. It is a story which is repeated over and over by ALL of US as we try to solve the worlds problems.

http://www.ncbi.nlm.nih.gov/pubmed/24383420

One final point. Although I am not familiar with your specific TNF alpha study, I will provide an explanation as to why all those biomarker trials failed.

Your study probably used the sepsis/septic shock criteria as a unified phenotype defining the “true state”. In hundreds of biomarker trials that has never been reproducible in over 2 decades.

TNF, IL6,. Procalcitonin, CRP, may each be useful for some phenotypes but since there is no unifying phenotype of sepsis they do not work well for that. One cannot identify a biomarker for a condition which does not exist or exists only in the minds of a thought leader group and their disciples.

This exposes another consequence of pathologic science. Industry realizes the science is sick and stops funding trials. This is the case today.

I have provided a plausible and well reasoned but politically unpalatable explanation as to why your studies and all the other biomarker studies failed. They all had a common fundamental flaw which rendered the science pathologic ( i e they all used of a guessed unified phenotype which does not exist as a standard for statistical analysis.)

So, I feel sorry for you just as I do for the ARISE team. You were probably unknowingly researching the 1980s unified phenotype of the sepsis dogma and no one can be successful doing that. This is hardly your fault. Everyone believed in the universal phenotype of sepsis in those days.

Of course we know better now . We are trying to generate epiphanies among excellent researchers like you which will open minds. We are trying to keep the young from following their well meaning mentors into the cul de sac.

We are at a dead end with industry pulling out and gov. grants still chasing the dogma (Paternal control of the science as a function of funding) . Yet shaking off the dogma we have learned much and future is very bright.

If you collected enough timed data on each case and get IRB approval we could re study your data to see if TNF proves useful certain phenotypes of sepsis within your subject group. We could do this for all biomarker trials and even ARISE if they collected enough timed relational data to characterize the phenotypes.

Anyone reading this, let me know if you have the data and desire to restudy your data against a wide range of dynamic relational sepsis phenotypes. We can provide funding for that effort.

I want to applaud again the courage of Dr. Simpson. We have reached out to many other sepsis thought leaders for over a year and they decline to defend their science. Perhaps they remain silent hoping for salvation as a function some miracle. Perhaps they are so convinced that they do not see the need to defend their dogma. More likely they are afraid. Subconsciously they must know there is no intellectual defense beyond the pragmatic arguments made by Dr. Simpson. No one is doubting that they are honest and not true believers of their own dogma.

I will leave you with a quote from Karl Popper who died 3 years after the sepsis dogma were promulgated.

“Normal science, in Kuhn’s sense exists. It is the activity of the non-revolutionary or more precisely, the not-so-critical professional: of the science student who accepts the ruling of the dogma of the day… In my view the ‘normal’ scientist is a person we ought to feel sorry for… He has been taught in a dogmatic spirit: he is a victim of indoctrination. I can only say that I see a very great danger in it and in the possibility of its becoming normal.”

Send links to these blog posts to the sepsis thought leaders and sepsis grant reviews and those who participated in ARISE, Process, and Promise. The fundamental flaw common in these studies will not be corrected (or reasonably masked) by a metanalysis which of course comprises the desperate new hope of present sepsis science.

As true believers we cannot expect the thought leaders to even see the need to defend their dogma but perhaps Karl Popper’s words will make them realize that they should be calling for consideration of reform of sepsis science as a matter of course, all the time, if only to avoid the risk of becoming “normal scientists”.

Most Respectfully,

Lawrence Lynn

Wow. So I think the real winner of this debate is in fact the reader, especially the young ones who can go on to carry the torch. In my opinion this fascinating debate between two experienced academics and clinicians, is really just about perspective. In actual fact, I’m fairly certain they both would treat the same septic patient in a similar fashion, with some fluids, antibiotics and vasopressors, but what we are talking about extends to the future of sepsis care, where both points of view are in fact necessary, the open-thought, “revolutionary” approach of Lawrence, as well as the practical one based on still-imperfect state of knowledge defended by Steven.   I do think that some of Lawrence’s rhetoric is likely a cause of inflammation and perhaps the cause would be best served by more “political” terminology, but my blog being the furthest thing from politically correct, it fits in well here. In his defence, he does acknowledge the immense contribution to the science from those he also takes a jab at. I think it is also a function of “the system” of institutions, journals and associations which inadvertently creates some of this paternalism, rather than it being really promulgated by the “thought leaders” themselves.  Having had the occasion  to interact with some of them myself, they are not all closed minded and religious – in fact, I find more of your “run-of-the-mill” intensivists to have that zealous follower’s attitude of not questioning what so-and-so says, whereas so-and-so himself is more likely to openly admit that hey, they weren’t sure if this was the best target/therapy/etc… but hey, gotta try something and see what happens.  So I hope this debate can help open a few minds, raise a few questions and provide some solid med-tertainment. 

Thank you and accolades to both Dr. Lynn and Dr. Simpson.

 

Cheers

 

Philippe

Cool stuff coming in 2015!

I gotta give a shout out to the #FOAMed world.  The last year and a half has been really stimulating, learning from and exchanging with an amazing cohort of peers, all striving towards self-improvement and saving a few extra lives. I’m also really thankful for all those who take a few minutes of their busy days to read or listen to some of the stuff I spew out, and truly appreciate comments and discussion.

Undeniably #FOAMed has made me a better doc, both from the standpoint of learning and inspiration, which is really the fuel behind continuing education. I’ve been involved in organizing events, and in fact, doing so, and the interaction with both the faculty and the participants has been, in and of itself, of immense worth in terms of motivation and a feeling of kinship to a like-minded group, which I think is very important to practicing physicians.

As a consequence of some of these #FOAMed introductions, some good things are in the planning stages for 2015.

Winter: check out BEEM january 26-28 out in Vancouver BC – I can’t make that but really wish I could.

Spring: Two really interesting events in collaboration with l’ASMIQ (Association des Specialistes en Medicine Interne du Quebec – Quebec internists), one being a half day on Shock & Resus (may 30th), and a full day on Lung Ultrasound (may 29th) featuring the grandfather of it all, guru Dr. Daniel Lichtenstein, the one who invented it (well…discovered it, technically). Both take place in Montreal. (Technically this is for ASMIQ members but if anyone is interested, let me know and I’ll see what I can do!)

Of course, CCUS 2015 takes place may 1-3 in Montreal. Can’t miss that. Register at http://www.ccusinstitute.org.

Summer? I’m not running anything, but definitely going to SMACC Chicago. Just go. ‘Nuff said. http://www.smacc.net.au.

Fall: Ken Milne (@TheSGEM) and I will be planning a really cool day combining a critical appraisal workshop and a review of acute care highlights, taking place in Montreal in the fall. Ken will teach us how to learn while being skeptical, and participants should leave with an important skill as well as a headful of practical knowledge. We don’t have a title for this yet but I’ll be sure to let you know! In the meantime be sure to check out Ken’s awesome stuff at http://www.thesgem.com. He keeps it real.

SGEM Ken

 

I’ve also been asked to organize an Ultrasound Simulation Workshop (we are doing an EchoSchockSim in CCUS 2015), which may also happen towards the end of the year.

 

conferences 2015

Ok, so that was just a bit of an update on what’s up in the next year. Hope to meet some of you at these events, do come and say hi!

cheers

 

Philippe

A Witnessed Arrest: Advanced Bedside Ultrasound. #FOAMed, #FOAMcc, #FOAMus

So I was taking over the ICU in the evening, and as I walked in I hear that an arrest had happened and she was now being wheeled out of the ICU to radiology for a CT head and CT angio. So I didn’t get to do a bedside exam.

The story was that an 84 year old woman who had been admitted for atrial arrhythmia had been noted to have different blood pressure in the upper extremities, and the concerned family had urged to hospitalist to seek additional opinions. At the very moment when she was being examined by but the daytime ICU doc and a cardiologist, she suddenly deteriorated. They were actually in the process of bedside ultrasound, which had been normal aside from a small pericardial effusion, when she became unresponsive, seemed to have some lateralizing signs, became bradycardia and arrested. They got ROSC with an epic within a couple of minutes.

The feeling was that, having been started on one of those NOACs (Eliquis), she had bled and arrested by neurocardiac axis. Definitely reasonable, but given the BP discrepancy, ruling out aortic dissection was also a must.

So here is the scan:

A quick glance reveals an ascending aortic aneurysm with what appears to be a dissection and a visible flap. The CT of the head was normal.  A closer look seems to reveal that the dissection extends into the brachiocephalic trunk.  My colleague discussed with the radiologist who repeatedly told him it was a type A but wouldn’t say anything more (don’t ask…). Just as a reminder, here is the current classification:

aortic dissection class

So in discussion with the family, there was obviously concern about the possible stroke (an early normal CT obviously does not rule out an ischemic infarct) and given that a palpable pulse does not exclude dissection, bedside ultrasound was the next step (also because the radiologist had not clearly pronounced himself on the scan – in all fairness he may have just done a preliminary reading – so here is what we see, with the carotid being in the lower right area of the flow box, and part of the jugular in the left upper.

As a comparison, here is the left side (normal – but inverted – jugular rt and carotid lt).

Clearly, most of the right carotid lumen is actually false lumen of the dissection, with only a small crescentic lumen between 3 and 6 o’clock. Not good.

Here are the basic cardiac views:

subxiphoid

parasternal long axis

 

We can see a small pericardial effusion which looks textured – likely blood, and essentially normal function.  Now here is a right-sided parasternal view, showing the dissected aneurysm, including the dissected intimal flap:

Now this isn’t a routine view, and honestly I did it after having seen the scan where one can see that the aneurysm abuts the chest wall, which would make it ultrasoundable, and i can’t really say I would have done it without that knowledge. But now I would, if a similar case would present itself. Very insensitive but quite specific.

So I thought this was an interesting case to show, as a rapidly developing clinical picture, and from the point of view of bedside ultrasound, it displays the usefulness of carotid imaging and alternate views – and how simple it is to do.  Unfortunately at her age and given state she was not deemed a surgical candidate and passed away the next day.

 

thanks for reading!

…to sharpen up your resuscitation and ultrasound skills, don’t forget to come to CCUS 2015, may 1-3 in Montreal, Canada!  Register at http://www.ccusinstitute.org and for more details,http://wp.me/p1avUV-aU

 

Philippe