Consider the Probe 3: So I've found the effusion, now what?

A 74 y/o F with pmhx of metastatic breast cancer, IDDM, HTN presents after a syncopal episode.  The patient notes that for the past 2-3 days she has been experiencing some lightheadedness and shortness of breath with exertion.  She is presently undergoing chemotherapy (I'd throw in some random chemo drus here, but lets face it, we wouldn't know them anyways...) and radiation.  She notes that she hasn't been eating/drinking very well.  She denies fever, cough, hemoptysis, leg pain/swelling.  She has mild nausea but no abdominal pain.

As you peek up at the monitor, you note that the patient’s HR is ~ 135 and her BP is 88/56.  Her O2 saturation is  99% and the nurse told you that she was afebrile.  Taking a look at this patient, she looks ill-appearing and anxious.  Her extremities are cool to touch.  You quickly decide that Room 33 might not be the best place to manage this patient and that she would be better served in a RESUS station.  As you wheel the patient to RESUS, you are trying to organize a mental game plan. 

You grab a quick accucheck (remembering that your pt is an insulin-dependent diabetic) which comes back normal at 115mg/dL.  You are appropriately concerned about this patient and feel the need to evaluate her for life-threatening pathologies such as pulmonary embolism, cardiac tamponade, pneumothorax, and large malignant pleural effusions.  Wouldn’t it be nice if there were a bedside tool that could help you quickly assess the patient for the aforementioned “can’t miss” diagnoses. 

I think you know where I am going, might be time to…CONSIDER THE PROBE.  I would strongly argue that for a hemodynamically unstable patient, Point-of-care ultrasound should be the initial tool utilized to guide workup in a dyspneic patient.  You help your RESUS nurse get your patient “plugged in” and pull in an ultrasound machine to perform a quick ECHO to guide your decision-making.  You grab a couple quick still images that get you more worried:

Diagnosing a patient with a pericardial effusion is nice, but what value does it serve us as emergency medicine physicians?  In this hypotensive patient with an impressive pericardial effusion at a quick glance, we need to get moving.  GET FLUIDS HANGING (if they aren’t already!) and then start scurrying around to gather a pericardiocentesis kit or (let’s face it) perhaps a Cook County makeshift kit (spinal needles tubing, 3 way stop cock?, get creative…).  Prepare yourself mentally and physically for the prospect that you may need to perform this rare, life-saving procedure!   If you have consultants in-house, GET THEM INVOLVED!  Cardiology should be your first call, but realize that they may want CardioThoracic surgery involved in this case.

You have a page out to cardiology, your equipment for an emergent pericardiocentesis is at the bedside. A 500cc NS bolus is in and the blood pressure improves to 98/60, HR comes down to 120.  You mentally review a recent ultrasound-college presentation on cardiac tamponade and remember how nice it is to be succinct but knowledgeable when communicating with your consultants.  You go back to the bedside and acquire the following echo clips so that you might have a more informed discussion with your consultants. 

Now, to review for a minute.  It doesn’t take too much skill as a bedside sonographer to identify a pericardial effusion.  However, it is much more difficult to assess for tamponade physiology.  Early signs of tamponade physiology include a Dilated IVC with Right Ventricular Diastolic Collapse.  This is easier said then done, especially when considering that these patients are often tachycardic.  Use Apical 4 chamber, Parasternal long or Subxiphoid and take a 5 second clip.  When reviewing these clips, assess the R ventricular free wall during diastole by slowing the clip down to frame by frame progression.  By noting the activity of the mitral (or tricuspid!) valve, you will be able to more easily separate SYSTOLE (Mitral/Tricuspid valves closed) from DIASTOLE (mitral/tricuspid valves open).  One really nice trick is to utilize M-mode in a Parasternal Long View.  Drop the M mode “plane” through the mitral valve (in the same location as we do to calculate an EPSS) and view this plane over time.  You should be more easily able to identify motion of the R ventricular free wall in relation to the mitral valve to assess for diastolic collapse as shown below:


The Yellow Circle above (familiar from measuring EPSS) illustrates the mitral valve snapping open towards the septal wall (indicating the start of DIASTOLE), while the Blue rectangle shows the R ventricular free wall collapsing inwards—indicating tamponade physiology!

After reviewing your bedside ECHO clips (above), cardiology agrees with your interpretation (R ventricular diastolic collapse indicating cardiac tamponade) and whisks the poatient off to the operating room for a pericardiocentesis with CT surgery prepared to perform a window if the pericardiocentesis fails. 

Take Home Pearls
1)     In a hypotensive and dyspneic patient, always CONSIDER cardiac tamponade in your differential diagnosis and then CONSIDER THE PROBE…

2)     Once you have diagnosed the effusion, use POCUS to assess for IVC dilation with RV free wall collapse during diastole as indicators of tamponade physiology—and a patient that is more likely to require urgent vs emergent pericardiocentesis.

3)     Utilizing M-mode on PSL view may help you to more precisely identify the movement of the RV free wall during Diastole vs Systole.

4)     Once POCUS has identified tamponade physiology, prepare yourself (mentally and physically) to perform a pericardiocentesis while concurrently reaching out to your consultants.


Nice intro/discussion through Dr. Avila’s 5 min sono:

Really awesome/in depth videocast from Mike/Matt that delves further into tamponade physiology:

Interesting article that highlights the subtelties of accurately diagnosing subacute tamponade:

As always check out Introduction to Bedside Ultrasound Ch: 17 (R Heart Pathology) to review this topic further:

Consider the Probe Take 2: Coming to Grips with your Fundoscopic Shortcomings....

49 y/o M with hx of HTN, HLD, IDDM presents with non-traumatic L-sided painless visual loss.  The patient states that several hours prior to presentation he developed blurry vision in his L eye.  On quick examination, there are no signs of trauma.  Visual acuity is 20/120 on the L and 20/40 on the R with normal intraocular pressures bilaterally.  Pupils are briskly reactive without any photophobia or consensual photophobia.  The lids, sclera, conjunctivae are grossly normal and there are no corneal defects with fluorescein staining. 

Coming out of the room, you are concerned about this sudden-onset blurry vision.  You remember a short lecture on visual acuity changes that Dr. Schindlebeck begrudgingly gave you in between his posting about sweater vests on Pinterest.  Your differential brings concerning diagnoses including central retinal arterial occlusion (CRAO), central retinal vein occlusion (CRVO), retinal detachment, as well as vitreous hemorrhage.  Now, our patient still has some visual acuity in the affected eye which speaks against CRAO (usually profound loss of visual acuity…unable to count fingers, etc.).  CRVO is certainly on the differential, but it is usually not a time-sensitive diagnosis to make.  That leaves us with retinal detachment vs vitreous hemorrhage.  Might be a nice time to CONSIDER THE PROBE!

Brushing up on the basics, ocular US is performed utilizing the high frequency linear probe. ALWAYS make sure you clean the probe prior to examination and use sterile gel packets.  You can consider placing a tegaderm over the closed eye to further protect it.  Fear not, you will not remove their eye-lashes when ripping the teggy off.  Finally, make sure to “brace” your hand on the bridge of the nose or the cheek as to avoid applying too much pressure to your patient’s globe.  Using plenty of gel, minimal pressure is needed to visualize both superficial structures (cornea, iris, lens) as well as the posterior chamber as shown below:


It sure beats your non-dilated funduscopic exam.  Anyways, let’s say you place the probe over your patient’s affected eye and ascertain the following image:


Noting the echogenic (hyperechoic) snake-like structure floating in the vitreous that ORIGINATES from the optic nerve (the optic nerve sheath is the hypoechoic “band” passing posteriorly from the vitreous chamber, see image above for anatomy review)—you are appropriately concerned that your patient may have a retinal detachment and needs urgent ophthalmologic consultation and you put a page out to the on-call resident.

Lets imagine that your bedside ultrasound of the affected eye had produced the following images/videos:

You note more globular hyperechoic material that swirls with kinetic maneuvers.  There is no “connection” to where the optic nerve originates.  Thus, you are less concerned for a retinal detachment and are moving towards a less time-sensitive diagnosis of vitreous hemorrhage.  Recognize that sometimes these hemorrhages can be subtle and may require you to adjust your gain (“lighten” your image) to visualize the abnormality.  While you still want to provide your patient with a prompt ophthalmology f/u appointment, you recognize that you probably don’t need to page the on-call consultant at 3:30 in the morning for a patient with these findings.  

Take it to the next level:

Like all things, Ocular US takes practice.  Fortunately, at Cook County we have an abundance of visual acuity complaints.  If you start imaging all of these patients early on, you will develop a good “eye” for normal vs abnormal findings.  One “next-level” step to ocular ultrasound involved further interpreting a patient with findings concerning for a retinal detachment to determine whether the macula is involved.  It is important to remember that the macula is the part of the retina responsible for “high-acuity” and central vision.  So retinal detachments can either involve this important region termed “Mac-Off” (macula detached) or they can spare it “Mac-On.”  To assess this, you must be able to localize the macula—it is immediately lateral to the optic nerve and usually inline with the middle of the lens (direct line of vision):


Now on account of the critical role the macula fulfills, any retinal detachment that spares the macula “Mac-On” requires EMERGENT optho consultation (that’s right, pick up the phone at 4AM…).  While patients that have already detached this region “Mac-Off” patients are slightly less time-sensitive and require URGENT follow-up.  The subtle difference between these findings is noted in the images below:

“Take Home Pearls”

1) Retinal Detachments appear as a snake-like hyperechoic extension floating in the vitreous that should “originate” from the optic nerve.

2) Vitreous hemorrhage appears as less well-defined hyperechoic “globular” debris in the posterior chamber.  It may be subtle and you may have to adjust the gain to visualize it. 

3) Retinal detachments that preserve the macula “Mac- On” require EMERGENT ophthalmologic consultation, while “Mac-Off” detachments are URGENT, but non-EMERGENT. 


5 Min Sono Video Retinal Detachment vs Vitreous Hemorrhage

Chapter 31 on Introduction to Clinical Ultrasound by Matt Dawson and Mike Mallin.  Still appears to be free on Itunes.  (

Random Youtube Video with nice example of “Mac-On” vs Mac-Off” detachment:

Weekly Fix - Nerve Blocks for Shoulder Reduction

Read the Blaivas paper on interscalene nerve blocks while listening to the podcast below.  For more FOAMed fun check out the Nerve Block page.