Wicked Clinical Case: POCUS & Prone save the day! #FOAMed, #FOAMcc, #FOAMer

So I get a call from a colleague in the ED at about 2am, telling me about a 39 yr old woman post-arrest. So I start putting on my boots and warming up the car (it’s January in Montreal folks).  Apparently she had presented earlier in severe acidosis, the diagnosis is unclear, but she apparently got 2 units for an Hb of 49, then went into respiratory failure and got intubated. She arrested about 30 minutes later, cause unknown.

I tell the ICU to prepare a bed but I want to see her in the ED first. Twenty minutes later I put probe to patient and see a full IVC with spontaneous echo contrast. On that I tell the nurse to hold the fluids – there was a bag and tubing and a pump with 100ml/hr on it – and turn into a subxiphoid view to see a normal RV and a hypokinetic LV with some WMAs. She has marked consolidations  in both posterior lung fields and B lines laterally, with small effusions and dynamic air bronchograms (indicating patent airways). At this point she has a HR of about 120, but there is neither perceptible BP (by NIBP) nor saturation. She’s on levophed at 20mcg. She’s about an hour post arrest which was witnessed and brief (<10min to ROSC).

The theories about the arrest are possible hyperkalemia: she was intubated with succinylcholine before the K of 6.1 was back from the lab, and her pre-intubation pH was 7.0, and post-intubation she was only ventilated at 400 x 18, possibly precipitating a drop in pH and a rise in K. Her EKG had some nonspecific signs at this point, but also a poor anterior R wave.

So we head to the ICU, as instrumentation was needed. Cerebral saturation (SctO2) is 42% and ETCO2 is 20mmhg, which reassures me that the BP is probably in the measurable range (normal SctO2 is >60% and varies, but 47% is certainly viable)…  A jugular CVC with continuous ScVo2 and a femoral arterial line goes in:

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So with a BP of 59/44 (ignore the 100/46, not sure whose arm that was on!) I start epinephrine, as the POCUS is similar, as I want some added beta-agonism. ScVO2 matches SctO2 in the 40’s. We get the BP up the the 90-1oo range, the ETCO2 goes to 30, the SctO2 and ScVo2 go up into the high 40’s, which is very reassuring, because with this I know that my epi drip is improving perfusion and NOT over-vasoconstricting. Without looking at a real-time tissue perfusion index of some sort or other, it is nearly impossible to know rapidly whether your therapy is helping or harming (will discuss tissue saturation & resuscitation monitoring in more detail in another post sometime soon).

screen-shot-2017-01-05-at-10-46-31-pm

So now the sat finally starts to record in the low 60’s. We have a PEEP of 5, so start bringing it up. We hit 16 before the BP starts to drop, and that only gets us to the mid 70’s sat%. She actually squeezes my hand to command.

screen-shot-2017-01-05-at-10-45-21-pm

At this point I take a few seconds to recap in my mind. I’d spoken to the husband briefly and she had had recurrent episodes of feeling unwell with headache, nausea and diaphoresis, and that had been out for dinner earlier and she felt fine until later in the evening when this came on and eventually brought her to hospital. There was also a notion of hypertension at an ER visit a couple of weeks ago. Her history was otherwise not significant. Nonsmoker.

Pheo? Maybe, but shock?  I repeat the EKG, and now, in I and AVL, there is perhaps a 1mm ST elevation. She’s 39 and essentially dying. Lactate comes back >15, pH 6.9.  I give her a few more amps of NaHCO3. You can see the BP respond to each amp. I decide we need to go to the cath lab and get the cardiologist on call to get on the horn with the interventional team at a nearby hospital with a cath lab and ECMO, which is what I think she needs. Hb comes back at 116, making that initial 49 that prompted 2 PRBCs probably a technical or lab error…very unfortunate. There are no visible signs of significant bleeding.

But back to the patient, because this isn’t really a transferrable case.

Recap: a 39yr old woman in cardiogenic shock AND in severe congestive heart failure exacerbated by fluids and packed red cells, with a PO2 in the 40’s and sat in the 70’s.

So I decide to prone her.

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Along with draining tamponades, this had to be one of the most rapid and rewarding maneuvers I’ve done. There was a scry drop of sat to the 40’s for a few seconds (may have been a technical thing), but then within a few minutes: BP to the 130’s, SctO2 to 59% and sat 100%!

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We dropped the vasopressors, the FiO2, and all breathed a collective sigh of relief. Now for the novices out there, prone ventilation improves VQ mismatch by moving perfusion from diseased, posterior lung fields to now-dependant, relatively healthy, anterior lung fields.

So transfer at this point was in the works. I planned to leave her prone until the last minute. The miraculous effect started to slowly wane within about 30 minutes, with sat and BP creeping down. At the time of transfer, we were back up to 80% FiO2.

So why is this?  Simple enough, this being simple pulmonary edema – rather than consolidated pneumonia – it migrated to dependent areas  relatively quickly. This was confirmed by a quick POCUS check:screen-shot-2017-01-05-at-10-48-06-pmscreen-shot-2017-01-05-at-10-48-26-pm

So in the still shots, you see a pristine “A” profile (normal, no edema) from the patient’s back, and a severe consolidation or “C” profile with ultrasound bronchograms in the antero-lateral (now dependant) chest. Impressive. (for those wanting some POCUS pearls see other posts and here). This is the reverse of her initial POCUS exam.

So we flipped her back and transported her – lights & sirens – the the cath lab, where they were waiting with ECMO cannulae. As an aside, it was quite refreshing to speak to the ICU fellow who spoke POCUS as well as french and english – it’s not usually the case, but I’m glad to see the change. I do believe it to be a direct effect of the influence of my friend and mentor, Dr. Andre Denault, one of the POCUS deities.

So she turned out to have a normal cath and a large adrenal mass. She did well on ECMO, being weaned off it today, and is now alpha-blocked and waiting for surgery, neurologically intact for all intents and purposes. A big thanks to the interventionists and the ICU team at the Montreal Heart Institute. Puts a smile on my face.

 

Take Home Points:

  1. don’t resuscitate without POCUS. I wouldn’t want anyone guessing with my life on the line, would you?
  2. keep pheo in mind as a cause of “acute MI” and shock
  3. if you’re not using some form of realtime monitor of perfusion (continuous CO, SctO2, ETCO2, ScvO2) then all you’ve got is looking at the skin and mentation, so you are essentially flying blind. Lactate and urine output are not realtime in real life.
  4. get ECMO in the house, it’ll come in handy. I’m working on it.

 

Love to hear some comments!

cheers

 

Philippe

 

ps I’ll try to add more ultrasound clips from this case in the next few days.

NIRS-Assisted Resuscitation: Following the N=1 Principle. (Part 1) #FOAMed #FOAMcc #NIRS

So for anyone who has been reading any of my stuff, you know that I believe we best serve our patients by using the information in good evidence and blending it with bedside assessment (ultrasound being an integral part of physical examination) and physiology to come up with the best therapeutic approach to the one patient we are treating.  Contrast that to the blinded and naive belief that one protocol from one study is the best thing for all patients suffering from disease X.

So I am constantly looking for a way to fine tune resuscitation to the individual patient, given his/her particular cardiovascular function, volume tolerance (not just volume responsiveness), vasopressor tolerance (blue fingers probably mean blue livers and kidneys to some degree) and metabolic reactions.

One of my friends and mentors is Dr. Andre Denault. Absolutely incredible guy who is a complete triple threat of academia (internist/intensivist/anaesthetist massively published), experience and raw neuronal power. Throw in open-mindedness and humility (he actually once picked my brain about abdominal compartment syndrome pressure monitoring) and you have a lethal package. So after killing off the filed of intraoperative/critical care TEE (yes the leading textbook is his), he’s plunged into NIRS spectroscopy and is now dragging it from the OR to the ICU, and so in the last few years he’s put me on this trail with anecdotes and his (unpublished yet but coming) findings.

So a quick few words about NIRS (Near InfraRed Spectroscopy). The technology looks at hemoglobin saturation, and does so in a predominantly venous way. Hence this behaves similarly to a central or mixed venous gas, except at the local tissue level. A gross normal is >70% but this has to be interpreted in clinical context, along with the knowledge of simultaneous arterial saturation. Hence lower values (assuming normal arterial sats) will mean one of two things: increased demand or decreased supply. The demand issue is a clinical one. What we are looking for using this type of monitoring is decreased supply, e.g. cardiac output that is inadequate for current demands.

The information gleaned from our discussions was enough to make me get some loaner time with some devices, and that was enough to have a few clinical cases pique my interest.

Here is one:

In the ICU at Scarborough General in Toronto, I admit a lady with urosepsis on a stone-obstructed hydronephrosis. We get urology to slip in a double J, but she is still very norepinephrine-dependant. She isn’t intubated, lactate about 5 and on high doses of norepi to maintain MAP 60-65. Extremities are cold and mottled and there is mottling up to the thighs. She is awake and communicating. Over the next hour or so lactate rises to 5.5. I’m not liking this.

I put on the NIRS monitor with a cerebral lead and one on the thigh. They both read in the 50’s, somewhat suboptimal.

Bedside US reveals a good sized IVC with little variation. She’s well filled. Her LVEF is 50-60%, her RV is dynamic and with a normal RV/LV ratio. The hydronephrosis is improved on the affected side.

So I have a patient who’s adequately preloaded, without obstructive or systolic failure, who is on very high doses of norepinephrine with a rising lactate, despite source control and antibiotics. However, she doesn’t “look” that bad aside from the cold and blueish extremities…

So I decrease the norepinephrine. Systolic BP drops to 80…but…cerebral NIRS and tissue NIRS rise…now in the high 50’s. Patient remains awake and communicating. Drop norepinephrine some more. Systolic 75. Cerebral NIRS 62%, tissue 61%. Systolic 70. Cerebral 59%, tissue 57%. Back up to 75%. NIRS back up.  I finally settle on 75-80 systolic. NIRS settles in low 60’s. An hour later, lactate is 4, two hours later 2.5, then normalizes. Over that time span, the mottling gradually resolves and the urine output picks up. By the next morning she is off norepinephrine, and her BP sits around systolic 85-90 on its own. Turns out her usual BP is in the low 100’s.

I’m not sure how long – without the reassurance of improved tissue saturation – I would have been able to tolerate systolic BPs in the 70’s. Remember that lactate takes time to clear and urine takes time to make.

So this case reinforced my belief that not every patient’s needs are best met by an MAP of 65, and that targeting this may be harmful. It isn’t hard to imagine a scenario (which I may very well have pursued at a more junior stage) where further fluid resuscitation, coupled with insistence on a BP value may have resulted in iatrogenic fluid overload or Paul Marik’s “salt water drowning” (more commonly thought of as “ARDS”) and tissue ischemia/organ dysfunction (partly related to over-vasoconstriction) and who knows what outcome could have transpired… And very possibly, a bad outcome may have been blamed on severity of illness… Food for thought.

So one definitely possible use for NIRS is to find the “sweet spot” for the BP/vasopressor relationship.

More on NIRS in Part 2 in the next week or so.

A Bedside Ultrasound Case & Poll: All Infiltrates Are Not Created Equal. #FOAMed, #FOAMcc, #FOAMus

So I get an early morning call from a really good ER guy informing me of a likely ICU admission: a young guy (30’s) with a bilateral pneumonia and fever whom he suspected might get worse before he got better. He’s given him some fluids and started ceftriaxone and azithromycin. Sounds good to me. Sold. I tell him I’ll come take a look as soon as I roll into work (we do home call).

An hour or so later I head to the ED and see a him, in bed at 30 degrees or so with nasal prongs, maybe a little tachypneic but certainly not in severe distress and not particularly toxic. The nurse informs me that his temperature was apparently 40 degrees. The CXR (I’ll try to put it up soon) shows bilateral infiltrates, more predominant in the lower two thirds of the lung fields. WBC is 14, lactate 2.3.

So this guy had been short of breath for about 2 weeks, having some cough and localized left sided pain associated with movement, cough and pressure. The cough was non-productive.  As I was getting this history (yup, generally bedside ultrasound is simultaneous with history-taking for me), this is what I see:

(parasternal long axis)

(parasternal short axis)

(right lower costal margin)

(you can see this in most of the lung fields)

He has no past medical history or notable family history, drinks occasional wine, has not traveled of late and works as an electrician. He is active and played soccer – the last time a few weeks ago. He came to the ED for dyspnea, but had still been able to go up several flights of stairs, albeit with more dyspnea than he normally would have.

 

 

 

check back tomorrow and let’s see what happens!

 

cheers!

 

Philippe

L’Échographie au chevet pour l’Interniste: ASMIQ/CCUS 2014, #FOAMed, #FOAMcc, #FOAMus

Belle journée aujourd’hui à a deuxième collaboration éducative entre l’ASMIQ (Association des Spécialistes en Médecine Interne du Quebec) et le CCUS, lorsque une trentaine d’internistes ont approfondi leur habiletés échographiques.

Tel que promis, et dans l’esprit de #FOAMed, voici les présentations et videos:

Dr. Ian Ajmo nous fait une revue de l’évaluation de la volémie, en particulier l’échographie de la veine cave inférieure (VCI):

présentation PDF gestion-voleěmie – copie

vidéo https://vimeo.com/96308958,

Dr. Anne-Patricia Prévost révise l’échographie pulmonaire et cardiaque ciblée:

presentations PDF ASMIQ 2014 coeur ASMIQ 2014 poumons

vidéos:

https://vimeo.com/96315383,         https://vimeo.com/96315382,

 

Merci aussi à Dr. Simon Benoit et Dr. Nicolas Buissières qui ont fait un travail excellent dans les ateliers pratiques!

 

Philippe

 

What’s this sign? Bedside Ultrasound Picture Quiz! #FOAMed, #FOAMcc, #FOAMus

Here is a one of the “classic” and physiologically important echocardiographic signs:

 

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What do you see in this parasternal short axis view, and what are the physiological implications?

Scroll below for the answer!

 

 

 

 

 

 

 

 

 

 

This is the “D” sign, aptly named for the D-shape taken by the LV (normally circular) when RV overload occurs and there is paradoxical septal motion and flattening, as early diastolic RV pressure exceeds early diastolic LV pressure.  This is NOT a good thing and points to a very strained hemodynamic pattern.

Note the RV is huge in this cut, bigger than the LV (remember that in all views, the RV should be about 60% of the LV size – this is simply due to the semi-lunar shape the RV takes as it “wraps” around the LV – they both have the same stroke volume). Also note the small posterior pericardial effusion.

So what is the diagnosis here?  Well there isn’t enough information to say with just this image.  This happens to be a case of worsening ARDS, but all you can tell is that there is acute right ventricular failure due to pressure overload, so that the diagnosis includes (a) PE, (b) acute pulmonary hypertension due to some kind of pulmonary disease – ARDS, pneumonia, etc…  Obviously, in the absence of significant parenchymal abnormalities on CXR or B lines/effusions/consolidations on lung ultrasound, PE should be strongly considered.

 

Happy scanning!

 

Philippe

Here is an excellent review on RV dysfunction and focused bedside ultrasound assessment:

RV bedside echo

or its link:

http://www.benthamscience.com/open/toccmj/articles/V003/SI0020TOCCMJ/38TOCCMJ.pdf