SonoCase: 46yo shortness of breath – guest post by Jacob Avila @UltrasoundMD #FOAMed

Our newest guest post is by one of the best emergency medicine resident educators I know – of course, you dont want to miss his educational pearls on twitter too – Dr. Jacob Avila. He discusses a case that illustrates how bedside ultrasound can help in your unexplained short of breath patient, and even cancel that triage bias that your attending can do to sway you away from the truth. Let’s give it to Dr. Avila for highlighting (with a great literature review) how ultrasound can help you too. Here it is – enjoy! (note: not all images were of this patient, but were taken from other resources)

“You arrive to the emergency department for your first night shift of the month, and as you place your bag on the desk, the attending walks towards you with a chart in his hand. “Do you mind seeing this patient? It’s a COPD’er with dyspnea.  It’s probably just a COPD exacerbation.”  You look at the chart and see that it’s a 46 year old female with shortness of breath.  As you walk into the room, you notice the patient appears slightly pale, is afebrile, has an O₂ saturation of 91% and is tachycardic in the 110’s with a blood pressure of 105/76, temperature of 98.5° and respiratory rate of 26.  While taking the history, you note that the patient is a smoker and recently returned from a 12 hour car ride to see relatives.  Suspecting that this may be something other than simple COPD exacerbation, you grab your ultrasound machine and start with the cardiac echo (as described in the RADiUS protocol) and are able to get the following image:

This apical 4-chamber view shows severe right heart dilation, defined as a RV:LV ratio >1.  However, you remember that the patient has a history of COPD, and chronic pulmonary hypertension can cause chronic right ventricular dilation1.  At that moment, the patient becomes hypotensive with a systolic blood pressure in the 70’s and develops severe respiratory distress. What should we do?

Early diagnosis of a pulmonary embolism (PE) is exceedingly important, as two thirds of patients with mortality associated with a PE die within the first hour of their presentation², and intuitively, those who are treated earlier generally have a better prognosis ³.  The definitive diagnosis of a PE requires the use of a CT scanner ⁴, but in a patient who is unstable, like this one, that isn’t an option. Looking at the right ventricular to left ventricular ratio is a maneuver that can rapidly change your differential diagnosis or confirm what you previously suspected. A recent study by Dresden et al found right ventricular dilatation identified by emergency physicians had a specificity of 98% for a PE.  That number is impressive, but when you look at the methodology section of the publication, only 10% of the patients they included had coexisting COPD, and all of the false positives in the study were in patients with COPD⁵.   One  technique that may help differentiate between chronic and acute dilation is looking at the RV free wall in the subxiphoid view while in end diastole. A free wall size >0.5 cm is more likely to be chronic RV dilation⁶ⁱ. However, this view is not always possible in all patients.  Another echo sign you could look for is the McConnell sign (apical winking of the right ventricle during systole), which previously was reported to have an impressive 94% specificity and 77% sensitivity for an acute PE^7l, but a subsequent and larger study found the McConnell sign to be only 70% sensitive and 33% specific for a PE⁸. Take a look at what the McConnell sign looks like”

 

Another, less commonly seen finding would be directly seeing the clot in the right atrium (RA) or in the pulmonary arteries.

Clot in RA:

Clot in pulmonary artery:

Of more practical use are two other sonographic findings: Deep venous thrombosis (DVT) and distal pulmonary infarction.

In a study that included 199 examinations, bedside 2-point compression evaluation of the greater saphenous/femoral vein junction and the popliteal veins of patients with suspected DVT was found to be 100% sensitive and 99% specific for DVT ⁹.   However, it is possible for a patient to present with an acute PE and have a negative DVT, and only about 40-50% of patients with DVT’s will end up having a PE^{10, 11}

DVT on one side diagnosed by noncompressible vein:

More recently, lung ultrasound has been explored for the assessment of a suspected PE. A recent systematic review and meta-analysis by Squizzato et al which included 10 studies and a total of 887 patients found lung ultrasound to have a mean sensitivity of 87% and a mean specificity of 82% for acute PE¹².  What they looked for in the lung was the presence of triangular, wedge or rounded hypoechoic, pleural based lesions.  These lesions are thought to be due to embolic occlusions that resulted in either focal atelectasis with extravasation of blood or focal infarction of the lung parenchyma . However, they state in their publication that “Several methodological drawbacks of the primary studies limit any definite conclusion”.

Lung infarction:

 

Instead of looking at just one specific sonographic finding for the diagnosis of acute PE, a better method may the use of multi-organ sonography.  Recently, Nazerian et al. published a study utilizing multi-organ sonography in the diagnosis of PE.  This study used echo, lung and DVT ultrasound to diagnose PE and found that when the three ultrasounds were combined, they yielded a sensitivity of 90%, which was significantly higher than each of the exams by themselves¹³.

Like any physical exam finding, lab reports or other radiographic assessments, the sonographic analysis of a patient with a suspected pulmonary embolism should be used as part of your diagnostic quiver, and not the silver bullet.  Any of the above mentioned ultrasound findings of acute PE can potentially be found in other,  non-PE causes of dyspnea.  DVT’s can just be DVT’s, RV enlargement can be chronic or from an RV infarction, and subpleural fluid collections can be seen in contusions, pneumonia  and cancer.  This doesn’t mean not to use it though.  Just think about all the other tests we use in the emergency department, such as EKG’s, chest x-rays, troponins, BNP, and the d-dimer.  All of these can be abnormal in PE and in non-PE entities.

Now back to our patient.  She is a 46 year-old female with COPD that had right heart enlargement, which we learned above can be  seen in COPD without the presence of a PE.  You were unable to get a good subcostal view of the heart to measure the lateral wall, mostly because the  patient did not tolerate being laid flat.  You move on to the lungs and in the lower right thorax and there you find two hypoechoic, pleural based lesions.  Heparin and a CT scan are ordered, and the CT scan shows a large clot located in the right main pulmonary artery.

Here is the CT scan showing the clot:

To see a recent podcast by Ultrasoundpodcast on multi-organ US for PE, go here.

References:

1. Otto, Catherine M.. Textbook of clinical echocardiography. 5th ed. Philadelphia, PA: Elsevier/Saunders, 2013. Print. p 247
2. Wood KE. Major pulmonary embolism: review of a pathophysiologic approach to the golden hour of hemodynamically significant pulmonary embolism. Chest. 2002;121:877-905
3. Jelinek GA, Ingarfield SL, Mountain D, et al. Emergency department diagnosis of pulmonary embolism is associated with significantly reduced mortality: a linked data population study. Emerg Med Australas. 2009;21:269-276
4. Goldhaber SZ, Bounamenaux H. Pulmonary embolism and deep vein thrombosis. Lancet 2012:379:1835-46
5. Dresden S1, Mitchell P2, Rahimi L2, Leo M2, Rubin-Smith J2, Bibi S2, White L3, Langlois B2, Sullivan A4, Carmody K5 Right ventricular dilatation on bedside echocardiography performed by emergency physicians aids in the diagnosis of pulmonary embolism. Ann Emerg Med. 2014 Jan;63(1):16-24. doi: 10.1016/j.annemergmed.2013.08.016. Epub 2013 Sep 27.
6. Rudski LG, Lai WW, Afilalo J, Hua L, Handschumacher MD, Chandrasekaran K et al. Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography endorsed by the European Association of Echocardiography, a registered branch of the European Society of Cardiology, and the Canadian Society of Echocardiography. J Am Soc Echocardiogr. 2010;23:685-713
7. McConnell MV, Solomon SD, Rayan ME, Come PC, Goldhaber SZ, Lee RT. Regional right ventricular dysfunction detected by echocardiography in acute pulmonary embolism. Am J Cardiol 1996;78:469e73.
8. Casazza F, Bongarzoni A, Capozi A, Agostoni O. Regional right ventricular dysfunction in acute pulmonary embolism and right ventricular infarction. Eur J Echocardiogr. 2005;6:11-4
9. Crisp JG, Lovato LM, Jang T. Compression ultrasonography of the lower extremity with portable vascular ultrasonography can accurately detect deep venous thrombosis in the emergency department. Ann Emerg Med. 2010;56:601-610
10. Kearon C. Natural history of venous thromboembolism. Circulation. 2003;107:22-30
11. Moser KM, Fedullo PF, Littlejohn JK, Crawford R. Frequent asymptomatic pulmonary embolism in patients with deep venous thrombosis. JAMA 1994;271:223-225
12. Squizzato A1, Rancan E, Dentali F, Bonzini M, Guasti L, Steidl L, Mathis G, Ageno W. Diagnostic accuracy of lung ultrasound for pulmonary embolism: a systematic review and meta-analysis. J Thromb Haemost. 2013 Jul;11(7):1269-78. doi: 10.1111/jth.12232.

13. Nazerian P, et al. Accuracy of Point-of-Care Multiorgan Ultrasonography for the Diagnosis of Pulmonary Embolism.Chest. 2014 May 1;145(5):950-7. doi: 10.1378/chest.13-1083

SonoCase: 60yo blunt chest trauma, 82yo with chest pain- in JEM by @ultrasoundREL

In a recent article in the Journal of Emergency Medicine, Dr. Resa Lewiss and friends, discuss 2 cases of thoracic aortic aneurysm identification by focused cardiac ultrasound. It is a great case report that highlights the need to include the aortic root and descending thoracic aorta in the parasternal long view of your focused cardiac echo.

“A 60-year-old man presented to the emergency department (ED) after a blunt traumatic injury to his back while at work. During the focused cardiac ultrasound examination, the aortic outflow tract distal to the aortic valve appeared enlarged and the aortic root measured 5.49 cm.

“An 82-year-old man with hypertension presented to the ED with 1 month of chest pain radiating to the back. The focused cardiac ultrasound examination demonstrated enlargement of the descending thoracic aorta at 4.82 cm.”

SonoCase: 61yr old with leg swelling, chronic cough, intermittent chest pressure – by Dr. Torregrossa et al. in @westJEM #FOAMed

This case is one where if I were the doctor, my immediate response may have been hidden from the patient. Inside voice would NOT have stayed in. Wow! Dr. Torregrossa and the team at USC discuss a case published in March 2013 Western Journal of Emergency Medicine of a patient where there obviously was no bedside ultrasound performed for the duration of his symptoms. “How long was that?” you may ask… ONE YEAR! Wow! He saw his doctor (check), he got a chest Xray (check), he got an EKG (check). Good thing he finally got an ultrasound study ….

The case: “61-year-old male with a 1-year history of bilateral lower extremity swelling and a chronic cough was referred to the emergency department (ED) for an abnormal echocardiogram. The patient also reported experiencing intermittent episodes of chest pressure. He stated that he was referred from his doctor after he received a cardiac echocardiography examination that showed possible mitral valve vegetations. On review of systems, he also admitted to intermittent chest palpitations. On physical examination, his vital signs included a blood pressure of 127/75 mmHg, heart rate of 80 per minute and regular, respiratory rate of 18 per minute, pulse oximetry of 98% and temperature of 98.0°F. The rest of the physical examination was normal. An electrocardiogram demonstrated normal sinus rhythm and the chest radiograph was unremarkable. ED bedside ultrasound (EUS) showed….”

To read on the topic so that you will know some of the literature behind it – go here.

SonoCase: 40yo: cough, fever, mylagias – typical viral infection? – By Teresa Wu/Brady Pregerson in EPMonthly #FOAMed

Drs. Teresa Wu and Brady Pregerson (in the current issue of EPMonthly) once again discuss an interesting case that is more than meets the eye, and thankfully they continue their humorous sarcasm and start the case by speaking of an average day in our emergency departments these days: “This is the third time this week that you have had to close your ED. All of the beds in the hospital are full, and your ED is bulging at the seams with sick patients that aren’t going anywhere anytime soon. You are holding 10 admissions at the present moment, and the hallways are lined with patients calling “doctor” every time you walk by. As much as you hate doing so, you concede to the request to close to ambulance traffic and then walk briskly over to the chart rack to see what you can do to help improve the current situation. Your eager intern is right on your heels and says he has a new patient to present to you. “This should be a really simple case,” he spurts out. You raise your eyebrows and bite your tongue.”……

They (meaning, the intern) describe a case of a 40 year old female who has had what seems like an upper respiratory infection for 4 weeks, that’s just not going away, and now with sharp chest pain worse when coughing. While going to evaluate the patient, they give one of the best pearls that all residents  should know: ““Teaching point number one is conservation of energy. One of the best ways to be efficient is to ensure that you minimize the amount of time wasted. If you might need the ultrasound machine, take it with you so you don’t have to walk back out of the room to go get it.” They then proceed to perform the beginnings of the RADIUS study, which highlights Echo, thoracic and IVC ultrasound for the short of breath/dyspneic patient. The patient complains of pain when lying back, which causes the spide-y sense to go up and be confirmed when seeing the below picture on the echo:

To read more on the case and their great clinical pearls click here to get to EPMonthly’s online site.

To read a prior post emphasizing the need to perform an ultrasound for any presumed or confirmed pericarditis by going through a another case… and some studies, click here.

SonoCase: 57 yr old with acute chest pain, light-headed….

This case is one of the most interesting cases I have heard about. A true testament to the concept that with bedside US, know what normal looks like well – because if you see something that doesn’t look normal, you may not know what it is sometimes, but it’s not normal and it’s time to explore further. One of our stellar EM residents, Dr. Natatcha Chough, went to the bedside of this patient who was brought by ambulance with appreciable diaphoresis. He was 57 yrs old, c/o gradual onset of chest pressure radiating to his back for 40 minutes (which had resolved after paramedics gave nitroglycerin), feeling light head, with associated shortness of breath, wheezing. He had a history of hypertension and aortic coarctation repaired as a child and at age 20, no history of asthma/COPD, and takes Metoprolol daily.

His vitals: T 36.3  RR 24   HR 83   BP  87/55   O2 sat 93% RA

SonoCase: 45 yr old female acute respiratory distress…. RUSH, part deux

Here’s another crazy case I had in the middle of the night in the ED, a night that was particularly… let’s say… challenging. Lots of patients (about 43 actually) and 2 thankfully great residents, and one other ED attending. We were busy supervising a chest tube placement, while overseeing the trauma next door and finishing our charts on other patients so they can be dispo’d (yup, multi-tasking at its best – [or worst, ya never know]) and we get a ring down of a 45 year old in acute respiratory distress placed on non-rebreather with subsequent vitals:  HR 130s   BP 80s/50    RR 38     90%O2 sat.

SonoCase: 25 yr old positional, pleuritic, chest pain. “It’s just pericarditis” Really?

Had a great case the other week of a patient who was previously healthy (“great” because of what it reminds us all to do with this diagnosis) , and other than a girlfriend who he fought with too frequently causing him to go into panic attacks and hyperventilate, he doesn’t have any other stressors in his life – psychologic or drug-induced (yes, I mean cocaine). He came to the ED c/o positional chest pain, worse when lying flat and breathing in, has been persistent for over a week with a recent viral syndrome but no current fever, cough or respiratory distress. He looked well, but felt tired, had no energy to walk a few blocks and that has been worsening over the week, which is when he got into another fight with his girlfriend about coming into the ED for evaluation. Thankfully, he lost and came in.