Limited EGDT in Zambia Study: Salt Water Drowning Syndrome… #FOAMed, #FOAMcc

So in this month’s issue of Critical Care Medicine, an interesting article was published, where investigators took a (necessarily) simplified version of EGDT to Zambia and applied it to septic patients. It turned out they had to stop it early due to an excessive number of cases of respiratory failure in the treatment group.  The difference was – you guessed it – they got “aggressive” volume resuscitation – up to 4l in the first 6 hours – guided by JVP assessment, and blood and dopamine if needed.

Simplified_Severe_Sepsis_Protocol___A_Randomized.1

The amounts received by 6, 24 and 72h were 2.9, 3.9 and 5.6 l for the treatment group vs 1.6, 3.0 and 4.3 l.

Now lets keep in mind that the patients, for the most part, did not have access to critical care, so the limited resources for ventilatory support made stopping the trial a bit early the only reasonable thing to do. Mortality in the treatment group was 64% and control 60%. High numbers, but this is explained in part by the prevalence of HIV (80%) and TB (37% of the HIV positive patients), so this data can’t necessarily be extrapolated to all populations, but to me, this is physiological support for the concept that aggressive fluid resuscitation – as I have stated in prior posts/podcasts – is most dangerous in those patients where the septic source – presumably “leaky” is ill-equipped to handle extra-physiological fluid.  In these patients, as Myburgh states in a sepsis talk, “noradrenaline is the fluid of choice,” and although perhaps a bit tongue in cheek, this certainly speaks to my beliefs of resuscitating to euvolemia rather than to the lack of volume responsiveness (http://intensivecarenetwork.com/myburgh-john-beta-blockers-and-sepsis/).

Additionally, these patients were not hypotensive, and lactate was not available – local limitations of medical system. Hence the definition of severe sepsis triggering aggressive fluid resuscitation was based  on SIRS type criteria, rather than some form of volume assessment.

 

Bottom line?

Be cautious in aggressive fluid administration in pulmonary sepsis. What, I really dislike when people say “be careful” or “be cautious,” because let’s face it, that doesn’t really mean anything, does it?  It doesn’t tell you what to actually do… We are frontline clinicians, so I’ll say to limit fluid resuscitation in pulmonary sepsis.  2 litres up front?  Probably ok so long as I have a varying, mid-size IVC (maybe 10-15mm – arbitrary and chronic pulmonary disease and hypertension have to be factored in) and a decent heart, but I don’t want to get to the point of no longer being fluid-responsive. Rather, go to pressors a bit earlier, perhaps, and no need for ongoing “maintenance” fluids at 100-150 cc’s an hour – remember that 80% of this wonderful therapy ends up where we don’t want it to.

 

cheers!

 

Philippe

PS for awesome talks by amazing speakers, don’t forget to register for CCUS 2015!!! For more info: http://wp.me/p1avUV-aU and register at http://www.ccusinstitute.org

The ARISE Trial: Sealing the Deal. #FOAMed, #FOAMcc

So I’m putting this up cuz I had a few people ask me to, but in truth I don’t think I have anything really groundbreaking to say, nor do I feel the need to repeat what Scott (emcrit.org) and the Bottom Line crew (wessexics.com) have already broken down.

I would just caution the following, as I did a few months ago with PROGRESS, that not all usual care is of the same level (and I’m not talking about the community vs academic centre necessarily) and you all know your institutions, so its up to everyone to judge whether they are better off sticking to their current (likely EGDT-based) protocols or not.

Anyhow, here it is:

 

Don’t forget:  CCUS 2015 registration opens soon!

see http://www.ccusinstitute.org or http://wp.me/p1avUV-bh for more details, its gonna be awesome!

Fluids and Vasopressors in Sepsis, Wechter et al, CCM Journal: Anything Useful? #FOAMed, #FOAMcc

A couple of articles on fluid resuscitation worth mentioning. Not necessarily for their quality, but because they will be quoted and used, and critical appraisal of the content and conclusion is, without a doubt, necessary to us soldiers in the trenches.

The first one, Interaction between fluids and vasoactive agents on mortality in septic shock: a multi-center, observational study, from the october issue of the CCM Journal (2014) by Wechter et al, for the Cooperative Antimicrobial Therapy of Septic Shock Database Research Group, is a large scale effort do shed some light on one of the finer points of resuscitation, which is when to initiate vasopressors in relation to fluids in the face of ongoing shock/hypotension.

So they reviewed 2,849 patients in septic shock between 1989 and 2007, trying to note the patterns of fluid and vasopressor therapy which were associated with the best survival.  They found that survival was best when combining an early fluid loading, with pressors started somewhere in the 1-6 hour range.  I do invite you to read it for yourself, it is quite a complex analysis with a lot of permutations.

So…is it a good study?  Insofar as a retrospective study on a highly heterogeneous bunch of patients, I think so. But can I take the conclusion and generalize it to the patient I have in front of me with septic shock? I don’t think so. In all fairness, in the full text conclusion the authors concede that this study, rather than a clinical game-changer, is more of a hypothesis generator and should prompt further study. That, I think, is the fair conclusion.

In the abstract, however, the conclusion is that aggressive fluid therapy should be done, withholding vasopressors until after the first hour.  This is somewhat of a concern to me, since it isn’t uncommon for some to just read that part…

So why is this not generalizable?  First of all, I think that the very concept of generalizing is flawed.  We do not treat a hundred or a thousand patients at a time, and should not be seeking a therapeutic approach that works best for most, but for the one patient we are treating. Unfortunately, this is the inherent weakness of any large RCT and even more so in meta-analyses, unless the right subgroups have been drawn up in the study design.

Let me explain.

Patient A shows up with his septic peritonitis from his perforated cholecystitis. He’s a tough guy, been sick for days, obviously poor intake and finally crawls in. If you were to examine him properly, you’d have a hard time finding his tiny IVC, his heart would be hyperdynamic, his lungs would have clear A profiles, except maybe for a few B lines at the right base. You’d give him your version of EGDT, and he’d do pretty well. A lot better than if you loaded him with vasopressors early and worsened his perfusion. Score one for the guideline therapy.

Patient B shows up with his septic pneumonia, also a tough guy, but happens to be a diabetic with a past MI. He comes is pretty quick cuz he’s short of breath.  If you examine him properly, he has a big IVC, small pleural effusions, right basal consolidation and B lines in good quantity. He gets “EGDT” with an aggressive volume load and progressively goes into respiratory failure, which is ascribed to his severe pneumonia/ARDS, but more likely represents volume overload, as he was perhaps a little volume responsive, but not volume tolerant. An example of Paul Marik’s “salt water drowning.” (http://wp.me/p1avUV-aD) Additionally he goes into acute renal failure, ascribed to severe sepsis, but certainly not helped by the venous congestion (http://wp.me/p1avUV-2J). If he doesn’t make it, the thought process will likely be that he was just so sick, but that he got “gold standard” care. Or did he?

It may very well be that the studied group may include more Patient A types, and less B types, whose worse outcome will be hidden by the “saves” of the As. If you have a therapy that saves 15/100 but kills 5/100 you still come out 10/100 ahead… Great for those 15, not so much for the 5 outliers.

We, however, as physicians, need to apply the N=1 principle as we do not treat a hundred or a thousand patients at a time. I would not hesitate to be much more conservative in fluid resuscitating a B-type patient, regardless of the evidence.

Unfortunately, until trials include a huge number of important variables (an accurate measure of volume status, cardiac function, capillary leak, extravascular lung water, etc), it will be impossible to extrapolate results  to an individual patient.  These trials will, I suppose, eventually be done, but will be huge undertakings, and I do look forward to those results.

So, bottom line?

It’s as good a study of this type as could be done, but the inherent limitations make it of little clinical use, unless your current practice is really extreme on fluids or pressors. What it will hopefully be, however, is an onus to do the highly complex and integrative trials that need to be done to determine the right way to treat each patient we face.

 

thanks!

 

Philippe

 

COMMENTS:

Lawrence Lynn says:

Excellent post. This thoughtful quote should be read and understood by every sepsis trialists!!

“We do not treat a hundred or a thousand patients at a time, and should not be seeking a therapeutic approach that works best for most, but for the one patient we are treating.”

This single quote exposes the delay in progress caused by the ubiquitous oversimplification which defines present sepsis clinical trials. Bacteria (and viruses) generate “extended phenotypes” which are manifested in the host. These phenotypes combine with the phenotypic host response to produce the range of “dynamic relational hybrid phenotypes of bacterial and viral infection”. These hybrid phenotypes are also affected by the innoculum and/or the site of infection (vis-à-vis, your example of peritonitis).

Certainly Wechter et al and the Cooperative Antimicrobial Therapy of Septic Shock Database Research Group should be commended for beginning the process of moving toward the study of the dynamic relational patterns of complex rapidly evolving disease and treatment.

We are excited to see the beginning of the move of trialists toward the study of dynamic state of disease and treatment. However, before they can help us with meaningful results, trialists will need to study and define the range of “the dynamic relational phenotypes of severe infection” and then study the treatment actual phenotypes. This will not be easy as these organisms have had hundreds of thousands of years of evolution writing the complex genotypes which code for the extended of human infection. Sepsis trailists need to be encouraged by clinicians to rise to the task.

The clinicians must actively teach the trialists, (as you have in your post) that we expect trails which help to identity the therapeutic approach that works best in response to the dynamic hybrid phenotype “we are treating”.

The two linked articles below explain the present oversimplified state of the science of sepsis trails and why we clinicians must teach the trailists not to oversimplify and assure that they move quickly toward the study of the actual dynamic phenotypes of severe infection.

http://www.ncbi.nlm.nih.gov/pubmed/24834126

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

This is a paradigm shift so we, as clincians, must act to teach trailists this move is necessary. Otherwise we will continue to be left with hypotheses, which, while nice, are not useful at the bedside.

Lawrence Lynn

 

 

Another wicked ultrasound case! Can you see the culprit? Another reason to do bedside ultrasound… #FOAMed, #FOAMcc, #FOAMus

Reviewing some TEE cases with Max Meineiri of TGH yesterday (Max is an anaesthetist-intensivist-sonographer extraordinaire who has been kind enough to help me brush up my TEE skills recently), here is one that stood out for two reasons. Here is the story: An 84 year old woman is sent from a peripheral hospital to the cath lab for chest pain.  She arrests on the table after they found normal coronaries and the code blue is called. Max arrives on the scene, and due to CPR making TTE difficult (and also because Max walks around with a TEE probe in a hip holster by Dolce & Gabbana), in goes the TEE probe and right away they note a massively dilated and hypokinetic RV, and a small and under filled LV. Yup, sure looks like a PE in these circumstances. Not being satisfied with a presumptive diagnosis, Max gets to a short axis view of the aortic valve and pulls out the probe slightly, following the bifurcation of the main PA.  On the screen, the right PA is on the upper left field, and the left PA disappears towards the upper right (the left main stem bronchus makes it difficult to visualize). Anything seem a little odd?   Yup, you can see the occlusive culprit a couple of centimetres into the right PA, moving with each beat.  Being in angio already, they threaded a PA cath and administered thrombolysis, but despite some visual fragmentation, she did not survive. So why is this case interesting? 1. the image is pretty cool. 2. More importantly, it highlights the importance of bedside ultrasound.  If a rapid, focused cardiac exam had been done at her presentation at the peripheral hospital, the first-line physicians most likely would have noted the severe RV dysfunction and questioned the diagnosis of coronary syndrome, possibly (hopefully) thrombolysing the patient, and very possibly averting the cardiac arrest. …I know, I know, we don’t have all the info, the ECGs, etc, and maybe this was really an ACS and she happened to have a DVT which embolized during transport, etc…do you buy that?  Ockham and his parsimonious razor don’t, and I would tend to side with them.   love to hear some thoughts!   Philippe

An Update on Pulmonary Embolism: NEJM’s PIETHO Study…what’s the verdict? #FOAMed, #FOAMcc

As has been discussed in a previous post (http://wp.me/p1avUV-7T), patients with sub-massive PE (hypoxic, tachycardic, some troponin rise, etc…but no hypotension) remain in a grey zone, which is, to me , a dubious situation at best – their mortality can be up to 15%, morbidity likely more.  Everyone agrees the low-risk patients don’t need thrombolysis, and everyone pretty much agrees that the patient in shock needs it.  There is data out there suggesting that some patients clearly benefit from thrombolysis despite not being in shock, in good part relating to avoiding chronic pulmonary hypertension and its consequences.

The issue for many clinicians is that they have a “stable” patient in front of them, and they are considering giving them a drug that can potentially give them a bleed in the head and leave them dead or crippled. Many shy away from this. Part of this is cultural, because the same docs probably wouldn’t hesitate giving the drug to a lateral or posterior MI, which is not likely to kill you, or even leave you a cardiac cripple (just to be clear, I’m not advocating against thrombolysis in these cases, just trying to find a parallel), but since the AHA guidelines say to do it and everyone else does it, there’s no trepidation. It is the standard of care.  For most of us acute care clinicians who do not do outpatient medicine, if the patient survives and gets discharged home, chalk one up in the win column. But, as has become clear in recent years with the post-critical illness syndromes, morbidity can be just as important as mortality, especially in the younger patients. Kline et al (Chest, 2009) showed how almost 50% of “submassive PE” patients treated with anticoagulation alone had dyspnea or exercise intolerance at 6 months. They only had a 15% improvement in their pulmonary artery pressures (mean 45 mmhg).

What are the real risks? Pooling the data together gives a value around 2% with a spread between 0.8% and 8%, more or less. This represents each patient’s inherent risk of bleeding, as well as some of the inconsistencies with post-thrombolysis anticoagulation (safest to aim for 1.5-2 x PTT baseline in the first 48h).

The MOPETT trial which, as a #FOAMite you have certainly come across, showed that a half-dose of TPA was highly effective, and they felt it might be possible to go lower. The physiological beauty in that is that, unlike other sites we thrombolyse with full dose TPA, the lungs get 100% of the TPA (coronary artery gets maybe 5%, brain gets 15%).  Mind you, of course, the culprit clot/artery obviously doesn’t get 100%, but much, much more (if we figure that you need about 50% vascular area occlusion to cause RV dysfunction) TPA per “clot” than other pathologies. One can argue that anatomically, there is a greater clot burden than coronary or arterial thrombolysis, which may offset this somewhat. However, the date was quite clear in this trial that the therapy was effective, and the bleeding was none.

Ok, so let’s get to the PIETHO. 1000 patients, TPA+heparin vs heparin alone in normotensive but intermediate risk patients. So, first question is how was that risk defined?  Patients needed to have echocardiographic/CT signs of RV dysfunction AND a positive troponin. Interestingly enough, onset of symptoms was up to 15 days before randomization…not exactly early treatment, and unfortunately there is no information about the actual time to thrombolysis or subgrouping.  The results were as one could imagine. The combined endpoint of death or hemodynamic decompensation was 2.6% in the thrombolytic group vs 5.6% in the anticoagulation.  I’m not a fan of combined endpoints. Hemorrhagic stroke was 2.0% vs 0.2%. Their conclusion? Exercise caution. Hmmm…not much of a step forward. Basically tells us what we know. It helps the hemodynamics, but you can bleed. They do re-affirm that bleeding is more likely in the over-75.

 

What do we REALLY need to figure out? 

1. echographic risk stratification – at least into moderate and severe RV dysfunction.

2. longer term outcomes (hopefully PIETHO has a follow-up study in the pipeline, since they had good numbers).

3. a point-of-care study – time is of the essence, and may have an impact on dosage. IMHO thrombolysis should be done within a few hours of presentation at most.

4. further dosage data – 1/2? 1/3? 1/4? small boluses q1h until RV function improves?

I wish I could do it, but community hospitals don’t have the ideal setup, nor do I have a research team that can handle something of this scale. But surely someone can!

 

Bottom line?

It won’t change my practice. I will continue to offer thrombolysis in select cases, especially the younger patients, who obviously have a lower risk of bleeding, and stand to benefit the most, as pulmonary hypertension  can be crippling. I know I’d take the risk of bleeding when I see 50% dyspnea/exercise intolerance two years down the road…

Finally, bedside ultrasound to anyone with dyspnea/hypoxia should be a standard of care for every acute care physician. No ifs, ands or buts, no exception. Waiting for a CT angio or formal (read daytime hours) echocardiogram is, to me, unacceptable. If you, a friend or family member were in that ER bed, would you trust a physical examination and a CXR to rule out the need for an immediate intervention? I wouldn’t, not my own, and not even Dr. Bates’, Dr. DeGowin’s or Dr. Sapira’s, or all three combined.

cheers!

 

 

 

Kline JA, Steuerwald MT, Marchick MR, Hernandez-Nino J, Rose GA. Prospective evaluation of right ventricular function and functional status 6 months after acute submassive pulmonary embolism: frequency of persistent or subsequent elevation in estimated pulmonary artery pressure. Chest 2009;136:1202e1210.

Guy Meyer, M.D., Eric Vicaut, M.D., Thierry Danays, M.D., Giancarlo Agnelli, M.D., Cecilia Becattini, M.D., Jan Beyer-Westendorf, M.D., Erich Bluhmki, M.D., Ph.D., Helene Bouvaist, M.D., Benjamin Brenner, M.D., Francis Couturaud, M.D., Ph.D., Claudia Dellas, M.D., Klaus Empen, M.D., Ana Franca, M.D., Nazzareno Galiè, M.D., Annette Geibel, M.D., Samuel Z. Goldhaber, M.D., David Jimenez, M.D., Ph.D., Matija Kozak, M.D., Christian Kupatt, M.D., Nils Kucher, M.D., Irene M. Lang, M.D., Mareike Lankeit, M.D., Nicolas Meneveau, M.D., Ph.D., Gerard Pacouret, M.D., Massimiliano Palazzini, M.D., Antoniu Petris, M.D., Ph.D., Piotr Pruszczyk, M.D., Matteo Rugolotto, M.D., Aldo Salvi, M.D., Sebastian Schellong, M.D., Mustapha Sebbane, M.D., Bozena Sobkowicz, M.D., Branislav S. Stefanovic, M.D., Ph.D., Holger Thiele, M.D., Adam Torbicki, M.D., Franck Verschuren, M.D., Ph.D., and Stavros V. Konstantinides, M.D., for the PEITHO Investigators*, Fibrinolysis for Patients with Intermediate- Risk Pulmonary Embolism, N Engl J Med 2014;370:1402-11.

Mohsen Sharifi, MDa,b,*, Curt Bay, PhDb, Laura Skrocki, DOa, Farnoosh Rahimi, MDa, and Mahshid Mehdipour, DMDa,b, “MOPETT” Investigators, Moderate Pulmonary Embolism Treated With Thrombolysis (from the “MOPETT” Trial), Am J Cardiol 2012

NEJM: The Septic Shock Issue…groundbreaking or same old same old? #FOAMed, #FOAMcc

Ok, so it was pretty cool to see an NEJM issue basically dedicated to septic shock management, I must admit. But let’s dig a little deeper, shall we?

So here is where they are: http://www.nejm.org, and fully available for now.

I won’t go through all the details and numbers, after all they are in the papers, so let’s just analyze them from two principles:

a. the N=1 principle – how was therapy individualized?

and

b. was there any integrated monitoring of the therapeutic goals?

…and we’ll conclude by looking at the potential practice-changing potential of each of these studies.

So first of all,

High vs Low BP Target in Septic Shock, by Asfar et al.

So basically a negative study except for two findings, the increased incidence of afib in the high target group and the decreased need for renal replacement therapy among chronic hypertensives in the high target group.

so N=1 is not really revealed:

“Refractoriness to fluid resuscitation was defined as a lack of response to the administration of 30 ml of normal saline per kilogram of body weight or of colloids or was determined according to a clinician’s assessment of inadequate hemodynamic results on the basis of values obtained during right-heart catheterization, pulse-pressure measurement, stroke-volume measurement, or echocardiography (although study investigators did not record the values for these variables).”

So lets just hope that the variability evens itself out between the groups, since we don’t really know. The numbers don’t really tell the tale, because the average fluids received (10 liters over 5 days) could mean one patient got 15 and one got 5 – although let’s trust they followed the French Fluid Resus protocol…

So the atrial fibrillation makes total sense – more B agonism should result in that, and the decreased renal failure also does.

As the authors note, the actual BP averages were higher than planned. For those of us practicing critical care, we know most nurses titrating prefer having a little bit of extra BP – even when I prescribe MAP 65, I usually see the 70 or so unless I make a point to tell them. Understandable. They also note the underpowered-ness of their own study, but I think it is still worth looking at their results.

So…bottom line?  I think it’s a great study for a couple of reasons.

The first is to remind us to pay a little more N=1 attention to the chronic hypertensives, and that it is probably worth aiming for slightly higher MAPs.

The second, debunking the myth of “levophed, leave’em dead” (which I heard throughout residency at McGill), and the concept of doing everything (ie juicing patient into a michelin man) in order to avoid the “dreaded and dangerous” vasopressors. So really I think an alternative way to conclude this study is that it isn’t harmful to have higher doses of vasopressors. I think this is actually a really good study on which to base assessment of more aggressive vasopressor support vs fluid resuscitation, in the right patients.

It would have been interesting to have echo data on those who developed a fib – were they patients who had normal to hyperdynamic LVs who in truth did not need B agonism at all and would have been fine with phenylephrine?  Perhaps…

Cool. I like it.

Next:

Albumin Replacement in Patients with Severe Sepsis or Septic Shock, by Caironi et al. The ALBIOS study (a Gattinoni crew)

So basically showed no difference, so pretty much a solid italian remake of the SAFE study in a sense, confirming that albumin is indeed safe overall, and may be better in those with shock.  As the authors note, mortality was low, organ failure was low, so study power a little low as well. Note the mean lactates in the 2’s at baseline. The albumin levels of the crytalloid only gorup were also not that low, low to mid 20’s, whereas I often see 15-20 range in my patients, especially if I inherit them after a few days, as I do use albumin myself a fair bit. They also used a target albumin level, not albumin as a resuscitation fluid purely.

In my mind the benefit of albumin would be greatest in those with significant capillary leak, particularly those with intra-abdominal and pulmonary pathology. It would have been nice to see a subgroup analysis where extravascular lung water was looked at (especially coming from a Gattinoni crew!).

Another interesting thing would have been to know the infusion time of the albumin, since animal data tells us that a 3hr infusion decreases extravasation and improves vascular filling vs shorter infusion times. I routinely insist on 3hr infusion per unit, which sometimes results in 9-12hr infusions, almost albumin drips!

Bottom line?

I like it. Reinforces that albumin is safe, so makes me even more comfortable in using it in the patients where my N=1 analysis tells me to be wary of third-spacing. Also the fact that they used 20% – in Canada we have 100cc bottles of 25% for the most part – is nice, since the SAFE data used 4%.

Next!

A Randomized Trial of Protocol-Based Care for Early Septic Shock – The ProCESS Trial.

So right off that bat my allergy to protocols flares up, so I’ll try to remain impartial. It just goes against the N=1 principle. The absolutely awesome thing about protocols is that it primes the team/system to react – so clearly protocols are better than no-protocol-at-all, but strict adherence would clearly not fit everyone, so that some built-in flexibility should be present.

This being said, the ProCESS study is really interesting, for a number of reasons. They have three groups, and compare basically (1) Rivers’ EGDT to (2) their own protocol (see the S2 appendix online) which gives a little more flexibility and (3) “usual care”.  Net result is that all are pretty equal, no change in mortality. As the authors note, their mortality was low, so again may not have been able to detect a difference.

So, what does this mean. To me it’s a little worrisome because I doubt that the “usual care” represents the true usual care found in EDs/ICUs all over the world, so I am concerned that many docs will use this as a reason to justify not changing their practice, similarly to many I’ve heard say they don’t need to cool anymore after the TTM trial. Human nature for some I guess.

Bottom line? You don’t have to follow EGDT if you’re conscientious and reassessing your patient frequently and have done all the other good things (abx, source control, etc). I think that’s really important because giving blood (see my post about S1P) to those with hb > 70 and giving dobutamine to patients with potentially normal or hyper dynamic LVs never made physiological sense to me, and the problem with a multi intervention study such as EGDT is that you can’t tease out the good from the bad or the neutral. Again, studies such as EGDT are pivotal in changing practice and raising awareness, so this is not a knock against a necessary study, just to highlight the point that each study is a step along the way of refining our resuscitation, and the important thing is to move on. In fact, the reason that this is a negative study is probably due to the improvement in “usual care” that EGDT brought along.

Conclusion: No new ground broken, but these studies do make me feel more confident and validated in continuing to not do certain things (strict EGDT) and  doing others (albumin and earlier use of vasopressors).

Kudos to all investigators.

 

let me know what you think!

 

P

 

CCUS 2014: Taking your Ultrasound Game to another level! Montreal may 9-11, 2014!

Registration is open!

For the 7th edition of our Annual Symposium, we’ve assembled a great cast of characters to bring your bedside ultrasound game to a whole new level! Whether you’re a novice or have some experience in bedside ultrasound, we’re sure you’ll find our program very interesting, as the perspective we have chosen to take is patient-based, with each lecture explaining how ultrasound findings are integrated into clinical decision-making.

First of all, it’s in Montreal, May 10th and 11th, 2014. If you’re from out of town, its an awesome city to visit, and if you’re a Montrealer, well, it’s an awesome conference at home!

Indeed, this isn’t “just” a “how-to” course – although that is what we’ll be covering in the workshops which will follow each lecture – but a “how to integrate ultrasound into your daily practice” course, so no matter what your level is, you’ll find something suited for you. The workshops will be divided into novice and experienced and with a low participant to faculty ratio, will ensure a great experience.

So what are we going to be talking about?

In the CC/ED/hospital scene:

–       the patient with chest pain, by Max Meineiri

–       the patient with CHF, by Mike Stone

–       the patient with renal failure, by Sara Sebbag

–       the patient with a swollenleg, by Michael Woo

–       what’s my patient’s volume status? By Ashraf Fayad

–       the patient with a decreased level of consciousness, by Robert Chen

–       the patient in shock, by JF Lanctot and Max Valois

–       the patient with abdominal pain, by Haney Mallemat

–       the patient with a bowel obstruction

–       the patient with broken bones: finding and freezing, by Catherine Nix

–       the patient with dyspnea, by Alberto Goffi and Edgar Hockmann (KEYNOTE)

–       the hemodynamically unstable patient: multi-modality assessment, by Andre Denault (KEYNOTE)

In the office scene:

–       the patient with a neck mass, by Sarah Sebbag

–       the patient with arthritis, by Alessandra Bruns

Here is the program:

CCUS 2014 Master Programme

Who made this up?  Our scientific committee is made up of Michael Woo, Catherine Nix, Edgar Hockmann, Alberto Goffi and Andre Denault, who is also the co-chair – with myself – of this year’s symposium.

For those of you part of the twitterverse and #FOAMed movement, you’ll get a chance to meet @criticalcarenow (Haney), @bedsidesono (Mike), @nobleultrasound (Vicki), @EGLS_JFandMax (JF and Max) and @ThinkingCC (yours truly)…and Matt (pulmccm.org) will be there to chronicle the event and bring the highlights to the #FOAMed world.

So who should come?  Anyone taking care of sick patients.  If you’re an ED doc, ICU doc, hospitalist, anaesthetist, surgeon, student or resident, this stuff is gold. Even if most of your practice is office-based, precise assessment of dyspnea, volume status and cardiac function is highly practical.

Additionally, there are several very interesting pre-congress courses taking place on May 9th, particularly the Echo-Guided Life Support course (JF Lanctot and Max Valois), a Bedside Ultrasound Course for Nurses, an Acute Care Procedures Course and a Symposium for Ultrasound Educators on how to set up training programs. All in all, a lot of great stuff.

For more details and registration, please go to www.ccusinstitute.org.  And yes, of course there are CME credits by the University of Montreal.

As I said a few months ago – well, tweeted, to be exact – if you’re an acute care MD and NOT using bedside point-of-care ultrasound, you’re stuck in the 20th century… rude, but true.

Hope to see you there!

Philippe Rola

President, CCUS Institute

Blood transfusion and serum S1P levels in Sepsis: a leaky proposition? (Protecting the Glycocalyx Part1) #FOAMed, #FOAMcc

So in my ongoing quest to reframe my resuscitation step-by-step, I’ve been following up on a number of leads regarding the glycocalyx, as previously stated, and John’s reference to this article in a previous comment I feel is highly relevant. So this is it:

Synergistic Effect of Anemia and Red Blood Cells Transfusion on Inflammation and Lung Injury,  Anping Dong, Manjula Sunkara, Manikandan Panchatcharam, Abdel Salous, Samy Selim, Andrew J.Morris, and Susan S. Smyth

Advances in Hematology, Volume 2012, Article ID 924042, 8 pages

http://www.hindawi.com/journals/ah/2012/924042/

S1P (sphingosine-1-phosphate) is a regulator of endothelial permeability and immune function.  Uh-oh, why had I not heard of it? Hmmm…I don’t think it was in Guyton’s or in Harrison’s…and there hasn’t been an RCT about it… Ok, that about explains it.

So here are some factoids about S1P:

–       serum levels correlate with HCT as RBCs serve as an S1P reservoir.

–       anemic patients’ S1P levels are NOT fully replenished by transfusion, especially the older the transfused blood is.

–       In fact, older RBCs may actually remove plasma S1P.

The study:

They basically took mice, and in the first group, bled them (by 20ml/kg) and looked at inflammatory markers, lung permeability and also S1P levels. That’s basically the control group, and they noted that hemorrhage significantly increased inflammatory markers (interesting in and of itself) . They then transfused these mice using wither fresh, S1P-loaded RBCs, or 14-day old RBCs, and, lo and behold, the fresh blood resulted in less inflammation, increased S1P, but most importantly, markedly decreased lung permeability. So clearly, S1P attenuates transfusion associated lung permeability.

In the next group, they injected the mice with LPS following hemorrhage, and found a synergistic effect of blood loss and LPS on inflammation and lung permeability, as could be imagined. Following the LPS, they were transfused with one of four strategies: fresh blood, old blood, fresh blood + S1P or old blood + S1P.  Well, lung permeability still increased in all groups, but least in the fresh blood + S1P, and the old blood + S1P a close second.

Note, interestingly enough, that saline alone (the “control”) also increased lung permeability, highlighting yet again that NS (and probably any crystalloid) is not innocuous…

So here we’re looking at the finer effects of transfusion, and why, against “common-sense” correcting a patient’s hemoglobin level does not seem to help in all situations.  We have understood the aging issue and loss of deformability, but it is time to take a finer look.  We are familiar – at least in concept – with transfusion-associated lung injury or TRALI, but the mechanism remains unclear.

Summary and Take-Home message:

S1P infusions in sepsis?  Maybe someday…

Yes, this is an animal study, and the results cannot be extrapolated directly to humans, but it is food for thought, as John had mentioned.  Certainly at least this should tell us to keep and ear/eye out for human work with S1P, but personally, it will make me even more comfortable in not transfusing my septic patients with hb’s in the low 70’s and maybe even high 60’s (try repeating the cbc, more often than not comes back a couple points higher and you can avoid transfusion), and for those who are a little more aggressive with transfusion, maybe this should make them think twice…

I’ll add what I can dig up on human S1P studies soon.

cheers!

Philippe

Transfusion and the Glycocalyx: John strikes again! #FOAMed, #FOAMcc

A great surprise this morning:  a comment from John. Yup, THE John. So taking a page out of Scott’s book, I thought it would be worth sharing with everyone as its own post, as opposed to just a comment. I think this is must-read material for everyone.

So without any further adue:

“I thought I might add some quirky ideas to your discussion.

We are now getting familiar with the concept of endothelial cells covered by a surface glycocalyx layer, that forms part of the barrier and mechano-sensing functions of the blood-tissue interface. We have discussed in some detail, the role of the glycocalyx in preserving endothelial integrity. I am gonna try and add a bit more spice into the whole transfusion drama.

In recent times, we have started talking a lot about a bioactive phospholipid called sphingosine-1-phosphate (S1P), as a crucial element in preserving vascular barrier integrity by ‘protecting’ the Glycolcalyx. (Most geeky papers on TRALI and other transfusion related complications do mention it).

Because albumin is one of the primary carriers of sphingosine-1-phosphate (S1P), it is possible that S1P, acting via S1P1 receptors, plays the primary role in stabilizing the endothelial glycocalyx. Infact, antagonism of S1P1 receptors have been shown to cause widespread shedding of the glycocalyx, as evidenced by increased serum concentrations of Heparan sulphate and Chondroitin sulphate. (This might probably be one of the mechanisms how albumin is glycocalyx friendly).

RBC transfusions are a double edged sword…..especially in situations of acute anemia as in post hemorrhagic situations ( major GI bleed or trauma.)….I totally agree with you in that the two are conceptually very similar.

Erythrocytes have been identified as an important buffer for sphingosine-1-phosphate . In mice, depletion of plasma S1P by genetic inactivation of S1P synthesizing enzymes (sphingosine kinases 1 and 2) elicits profound pulmonary vascular leak, which can be reversed by restoring circulating S1P via RBC transfusion.

In humans, hematocrit (Hct) predicts plasma S1P levels. There also seems to be a dynamic equlibrium between SIP levels of the plasma, and the circulating RBCs. It has been demonstrated that in anemic individuals, plasma S1P levels are not uniformly restored by RBC transfusion. Rather, the age of the RBC unit at the time of transfusion tended to negatively correlate with the ability of RBC transfusion to replenish plasma S1P. During storage, the S1P content of human RBC markedly declines, likely due to enzymatic degradation. Because erythrocytes serve as a buffer for circulating S1P, aged RBC with low S1P content may be incapable of restoring plasma S1P levels and may actually remove S1P from plasma, which in turn could contribute to increased endothelial permeability, capillary leak, and infiltration of inflammatory cells.

I hope this partly answers your question as to how the glycocalyx may be impacted by inappropriate and irresponsible transfusion triggers. I agree that these are all very novel ideas and as such, exist in the realm of experimental clinical physiology, but my gut tells me that the delicate Glycocalyx may hold the clue to a lot of answers to questions that have plagued us for a long long time!

Cheers,
John from India…”

So first of all, thank you very, very much for reading and taking the time to comment and enlighten us.

As John says, this is still in the realm of experimental physiology, but I think there are a lot of situations we are faced with, perhaps grey zone areas where we debate two potential therapeutic avenues, where we can use some of this data. We might debate giving that extra bit of fluid, or debate crystalloid vs albumin, or blood or no blood with an Hb of exactly 70, and I think we have to start weighing in some of this physiological data, even if it isn’t “evidence-based-by-RTC” to help guide these decisions.

The more I look into it the more it seems that our interventions – particularly fluid resuscitation, needs to be reassessed from the ground up both in nature, quantity and rate of infusion while measuring glycocalyx damage – e.g. biomarkers such as S1P, heparan or chondroitin sulfate, etc…

I’ve previously posted and podcasted about my general strategy for fluid resuscitation, and I am definitely in the process of revising it, still unsure what is best. I’d love to hear how John resuscitates his patients…

thanks!

Philippe

Other Comments:

Mystery John has an uncanny ability to describe complex physiology in the simplest way possible. I am very interested in digging more into his predictions of the possibility of aged erythrocytes removing S1P from circulating plasma.

Dr. John, if you’re out there, could you point us all to some of these studies you’ve mentioned? Any good S1P review papers you’d recommend to those, like me, who are S1P novices?

Thanks for your input! It was a pleasure.

Warm regards,

Derek

Thank you Derek, for the kind comments…. I think the concept of S1P is still in the process of evolving and assuming a definitive shape, so a good review might be hard to stumble across.

A good research article which cites some excellent references might be —

Synergistic Effect of Anemia and Red Blood Cells Transfusion on Inflammation and Lung Injury
— Anping Dong et al. (It is open access at http://dx.doi.org/10.1155/2012/924042).

Hope this helps……

John.

Here is the article:

924042

P

The N=1 concept. #FOAMed, #FOAMcc

First of all, happy holidays to all and happy new year!

Following a few requests, I’m gonna put up a few words about the N=1 concept, as I think it comes up in every single therapeutic and diagnostic strategy.

We do not treat a thousand, a hundred or even ten patients at a time.  As clinicians, we deal with a single patient, with a certain pathology, and his own, unique physiological pattern of response to that pathology.

In a medical utopia, we would be able to have a precise biophysiological profile of our patient – probably including parameters that either don’t yet exist, or are on the verge of being found or invented.  We would know, for instance, the degree of glycocalyx damage, the nature of this damage, the degree of subsequent capillary leak, the specific inflammatory cytokine pattern, and thus be able to use a potential combination of agonists and antagonists to favor healing, and tailor fluid therapy to the “just right” amount, avoiding both under-resuscitation and tissue edema. This would be similar to antibiotic sensitivity testing. Who, in this century so far, would deliberately not order sensitivities, instead satisfying themselves with a positive result and happy with empiric therapy?

Just in terms of biological variability, it is impossible to believe that all patients would respond best to a single goal or therapy. How can an MAP of 65 be as good for a septic hypertensive patient as it is for a young septic woman who normally walks around with an SBP of 110? Not that I don’t use that number myself most of the time, but certainly food for thought, and something to keep in mind when treating either of those “types” of patients…

And the answer to the N=1 riddle isn’t just subgroup analysis. The questions have to be answered in prospective fashion, built into the study design. Not easy work, and especially since we don’t yet even know what the key variables/questions are… But personally, as mentioned in an earlier post, I do now suspect that the ubiquitous glycocalyx holds some of those answers.

Let’s look at the whole fluid debate through the N=1 lens: it makes no sense whatsoever to debate crystalloids versus colloids. This negates thinking and only encourages near-religious fervour amidst both camps. Rather, look at your patient. Is he truly dehydrated/volume depleted or just volume responsive on the basis of vasodilation. If we want to restore the ICF and the interstitium, then crystalloids are probably better, but if we want to restore effective circulatory volume, then some measure of colloid may help avoid excessive edema, though even this can be debated. Even more important is the composition of the resuscitation fluid. Much as we adjust our TPN, we should probably design our resuscitation fluids, rather than only using Ringer’s Lactate (I say only just to drive the point that NS should not be used as a resuscitation fluid, unless repleting chloride is specifically necessary).

Now this may sound like a rant against large trials, but it isn’t. Absolutely invaluable information can be derived from these, it is just a matter of thinking how that information can benefit the one patient you have in front of you. And this isn’t easy. You have to put together your history, physical exam, bedside ultrasound exam and labwork. You can’t just say  “sepsis? 2 litres,” or any other such recipe (aka protocols).

ok, enough for a january 1st!

 

Love to hear what anyone thinks!

 

Philippe