Nephrolithiasis: Ultrasonography versus Computed Tomography

Written by: Kishan Ughreja , MD (NUEM ‘23) Edited by: Ade Akhentuamhen, MD (NUEM ‘21)
Expert Commentary by: Tim Loftus, MD, MBA

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Journal Club: Ultrasonography versus Computed Tomography for Suspected Nephrolithiasis

A 70-year-old man with BPH s/p TURP, hypertension, hyperlipidemia and stroke presents to the ED with acute onset of intermittent sharp left flank pain radiating into the groin that awoke him from sleep. He endorses nausea without vomiting and denies fever. He also endorses slightly decreased urination with “dribbling.” His urinalysis shows >100 RBC and no signs of infection. Nephrolithiasis is likely high on your differential diagnosis. How do you proceed?

What is your initial imaging test of choice, ultrasound (US) or non-contrast CT, and why?

Would you be satisfied with only US and no follow-up CT?

Would you be confident in a point-of-care-ultrasound evaluation or a formal ultrasound?

Do outcomes for patients with suspected nephrolithiasis differ based on the initial imaging?

Should your medical decision-making change if the patient has a history of nephrolithiasis?

What would you do if the same patient presented again with persistent pain from a previously diagnosed stone?

Pain from suspected nephrolithiasis is a very common complaint in the ED and the incidence of the disease continues to increase. The estimated incidence over the past two decades is up to 340 visits per 100,000 individuals.1 Low-dose non-contrast abdominal CT has become the gold standard for diagnosis as it has become readily available in emergency departments nationwide, with some studies touting sensitivity and specificity of 97% and 95%, respectively.2  However, low dose CT still exposes the patient to radiation and may increase their risk of cancer, as many nephrolithiasis patients often undergo repeat imaging because of recurring pain or urological intervention. Additionally, CT scans prolong average ED lengths of stay.  However, with ultrasonography becoming more prevalent in EDs, it may be possible that initial imaging may avoid this radiation risk and still have similar outcomes for patients. Let’s analyze this NEJM article comparing US to CT for the assessment of nephrolithiasis.

Study design: a multicenter, pragmatic, randomized comparative effectiveness trial

Population

• N = 2759

• ages 18- 76 yo

• reported flank or abdominal pain that the treating physician wished to order imaging to establish or rule out a primary diagnosis of nephrolithiasis

• not considered at high risk for serious alternative diagnoses e.g. cholecystitis, appendicitis, aortic aneurysm, or bowel disorders

• no pregnant patients

• no men >129 kg, no women >113 kg

• no history of single kidney, renal transplantation, undergoing dialysis

Patient selection

Intervention protocol

• patients randomized to 3 groups each using a different initial imaging modality (POCUS vs. Radiology US vs. CT)

• patients contacted at 3, 7, 30, 90, and 180 days after randomization to assess study outcomes

Outcome measures

Primary Outcomes

• high-risk diagnoses with complications that could be related to missed or delayed diagnoses — within 30 days of ED visit, including:

• AAA w/rupture, PNA w/sepsis, appendicitis w/rupture, diverticulitis w/abscess or sepsis, bowel ischemia or perforation, renal infarction, renal stone w/abscess, pyelonephritis w/urosepsis or bacteremia, ovarian torsion w/necrosis, aortic dissection w/ischemia

• cumulative radiation exposure from all imaging within 6 months after randomization

• total cost (not reported in this study, ongoing analysis)

Secondary Outcomes

• serious adverse events (FDA definition) 

• serious adverse events related to study participation

• delayed diagnosis, like acute cholecystitis, appendicitis, bowel obstruction

• return ED visits

• hospitalizations after being discharged from ED

• self-reported pain scores

• diagnostic accuracy for nephrolithiasis

• by comparing ED diagnosis at discharge to reference standard of confirmed stone by patient’s observation of passage or report of surgical removal

Results

• no significant differences among groups in terms of pain scores, medical history, physical exam findings, and ED physician’s assessment of the likelihood of other diagnoses (Table 2)

• POCUS and US groups had significantly lower cumulative radiation exposure over 6 months than the CT group (difference attributed to initial ED visit’s imaging choice)

• 11 patients (0.4%) had high risk diagnoses with complications during first 30 days after randomization, with no significant difference among the 3 groups

• no difference when stratified by patients with a history of nephrolithiasis

• no significant difference among groups in the number of patients with serious adverse events; total of 466 SAE in 316 patients (91.4% were hospitalizations during f/u period; 26.4% involved surgical treatment of complications of nephrolithiasis)

• 5 reported deaths (occurred between 38 and 174 days after randomization) — none thought to be related to study participation

• the proportion of patients with a confirmed stone diagnosis within 6 months was similar in all 3 groups (POCUS 34.5% vs. US 31.2% vs. 32.7% CT)

• diagnostic accuracy based on result of initial imaging modality

  • POCUS          sensitivity 54% [48 - 60]; specificity 71% [67 - 75]

  • US                   sensitivity 57% [51 - 64]; specificity 73% [69 - 77]

  • CT                   sensitivity 88% [84 - 92]; specificity 58% [55 - 62]

Interpretation

• The US group was exposed to less radiation than the CT group and had no significant differences in the incidence of high-risk diagnoses with complications, total serious adverse events, or related serious adverse events.

• There also were no significant differences in pain scores, hospitalizations, ED readmissions among the groups.

• Many patients in the ultrasound groups did get additional imaging, but this was not the majority.

• Patients with a history of nephrolithiasis were less likely to undergo additional imaging with CT if they already had an ultrasound first (31% vs 36%). They did not have poorer outcomes than patients without a history of nephrolithiasis.

• Patients only undergoing POCUS and no other testing had a significantly shorter ED stay (1.3 hours)

• It is safe to pursue ultrasound as the initial imaging of choice for suspected nephrolithiasis (with additional imaging ordered as necessary at clinical discretion), though it should not necessarily be the only testing performed.

Strengths

• large size, diversity in ED settings, randomized design, assessment of clinically important outcomes, a high follow-up rate

Weaknesses

• no blinding of investigators, physicians, or patients as this was a pragmatic trial design

• independent review was used to characterize serious adverse events related to study participation

• strict reference standard for stone diagnosis which was unbiased, but prone to error based on the patient’s memory of self-reporting of stone passage

Internal/external validity

• Given the aforementioned strengths of this study and its pragmatic design, these findings appear both internally and externally valid and may be applied to daily clinical practice

Take-Home Points

What is your initial imaging test of choice, ultrasound (US) or non-contrast CT, and why?

• Ultrasound is a good choice for initial imaging as most patients do not end up requiring additional imaging during their visit. This leads to reduced cumulative radiation exposure.

Would you be satisfied with only US and no follow-up CT?

• In this study, 40.7% of those in the POCUS group and 27% in the formal ultrasound group underwent subsequent CT. Follow up CT should depend on the patient and ultrasound operator. Keep in mind that this study excluded patients with kidney disease, pregnant patients, and obese patients. They also excluded patients who were high risk for other pelvic and abdominal diseases. Lastly the POCUS operators were ED physicians with training “recommended by ACEP.”

Would you be confident in a point-of-care-ultrasound evaluation compared to a formal ultrasound?

• Yes. Sensitivity and specificity between these groups were similar.

Do outcomes for patients with suspected nephrolithiasis differ based on the initial imaging?

• No. There was no significant difference in subsequent adverse events, pain, return visits or hospitalizations, or delayed diagnoses of other serious conditions.

Should your medical decision-making change if the patient has a history of nephrolithiasis?

• In this study, patients with a history of nephrolithiasis were less likely to undergo additional imaging with CT if they already had an ultrasound first. They did not have poorer outcomes than patients without a history of nephrolithiasis. This suggests that it is safe to avoid ordering a CT in patients with recurrent stones.

What would you do if the same patient presented again with persistent pain from a previously diagnosed stone?

• The majority of patients with adverse outcomes were due to infectious causes. Consider alternative diagnoses such as pyelonephritis. Additionally, although rare, renal infarct can present with acute flank pain and is diagnosed with a contrast CT.

References

1. Fwu, C. W., Eggers, P. W., Kimmel, P. L., Kusek, J. W., & Kirkali, Z. (2013). Emergency department visits, use of imaging, and drugs for urolithiasis have increased in the United States. Kidney international, 83(3), 479-486.

2. Coursey, C. A., Casalino, D. D., Remer, E. M., Arellano, R. S., Bishoff, J. T., Dighe, M., ... & Leyendecker, J. R. (2012). ACR Appropriateness Criteria® acute onset flank pain–suspicion of stone disease. Ultrasound quarterly, 28(3), 227-233.

3. Smith-Bindman, R., Aubin, C., Bailitz, J., Bengiamin, R. N., Camargo Jr, C. A., Corbo, J., ... & Kang, T. L. (2014). Ultrasonography versus computed tomography for suspected nephrolithiasis. New England Journal of Medicine, 371(12), 1100-1110.

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Expert Commentary

Thank you very much to Dr.’s Ughreja and Akhetuamhen for an excellent blog post on a very relevant clinical topic.  This is a great summary of the landmark randomized trial published in NEJM in 2014 assessing CT vs two types of US for patients with suspected renal colic in the ED setting.  It is worth mentioning that this study was a multicenter study based in the US with representation from ED, Radiology, and Urology.  The above study was well summarized and bears repeating that, in this multicenter randomized study assessing CT vs POCUS vs radiology performed US in patients with suspected renal colic in the ED setting, initial US reduced radiation exposure without adversely affecting patient-centered outcomes.  It is worth mentioning several additional considerations and placing emphasis on others elucidated from this journal club review.

First, a subsequent systematic review (1) incorporating multispecialty (ED, Radiology, Urology) expert panel consensus recommendations has reiterated that in younger patients without a high suspicion for alternative diagnoses or complicating features of nephroureterolithiasis (such as fever, pyelonephritis, solitary kidney, dialysis, etc), US should be the initial diagnostic imaging modality of choice, if any.  It's a great paper, worth reading (and appreciating who the authors are), and worth recalling for bedside teaching to junior learners in the ED. 

Additionally, this paper brings to mind my second point, and something that is worth shouting from the hilltops -- a kidney stone is a clinical diagnosis!  Now, of course, this is exclusive of those patients with high-risk or complicating features (e.g. pediatrics, pregnancy, solitary kidney, fever, unstable/critically ill, unrelenting pain, atypical features, etc).  You don’t need any imaging to tell you the diagnosis in the vast majority of patients.  US or CT are helpful in confirming the diagnosis when there is uncertainty or non-trivial pretest probability of alternative diagnoses, excluding alternative diagnoses, and identifying exact stone location and size, which can be used to help counsel patients at the bedside regarding the anticipated clinical course and next steps in management. 

 Third, for those with proper training, and with some exceptions (see the systematic review paper for case vignettes that highlight these), POCUS is non-inferior to radiology-performed US.  And, it's not a “formal” US.  I can’t remember the last time I attended a black-tie ultrasonography session, but that's just me. 

 Fourth, it's worth mentioning that although CT use can lead to the identification of incidental findings more commonly than US, identification of these incidental findings still happens rather often with POCUS (a common example is a renal cyst).  Please ensure that you document and discuss with the patient accordingly.

 Finally, a burden on us as EM clinicians is training in and awareness of clinical practice guidelines and recommendations from specialties outside of EM.  As it relates to the diagnostic evaluation of suspected renal colic in the ED setting, the Choosing Wisely recommendations endorsed by the AUA are worth perusing as are the European/EUA guidelines, both of which suggest US as the initial diagnostic imaging modality of choice, for pediatric (CW) and non-high-risk patients without complicating features (EUA).

The bottom line is that CT is helpful for older patients or those in whom you are less sure about the diagnosis of renal colic.  For younger or low-risk patients, suspected renal colic is a clinical diagnosis and often needs no imaging, but ultrasound would be an evidence-based first step.  Thanks again toDr.’s Ughreja and Akhetuamhen.

References

1) Moore et al. Imaging in suspected renal colic: a systematic review of the literature and multispecialty consensus. J Urol 2019. 202(3):475-483.

Tim Loftus, MD, MBA

Assistant Professor of Emergency Medicine

Fellowship Director of the Clinical Operations and Administration Fellowship Program, Northwestern Department of Emergency Medicine

Medical Director of Emergency Services Northwestern Lake Forest Hospital and Grayslake Emergency Center

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How To Cite This Post:

[Peer-Reviewed, Web Publication] Ughreja, K. Akhentuamhen, A. (2022, May 16). Journal Club: Ultrasonography versus Computed Tomography for Suspected Nephrolithiasis. [NUEM Blog. Expert Commentary by Loftus, T]. Retrieved from http://www.nuemblog.com/blog/nephrolithiasis-ultrasonography-versus-computed-tomography.

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Sono Pro Tips and Tricks for Acute Appendicitis

Written by: Morgan McCarthy, MD (NUEM ‘24) Edited by: David Feiger, MD (NUEM ‘22)
Expert Commentary by: Shawn Luo, MD & John Bailitz, MD

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Welcome to the NUEM SonoPro Tips and Tricks Series where Local and National Sono Experts team up to take you scanning from good to great for a particular diagnosis or procedure.

For those new to the probe, we recommend first reviewing the basics in the incredible FOAMed Introduction to Bedside Ultrasound Book, 5 Minute Sono, and POCUS Atlas. Once you’ve got the basics beat, then read on to learn how to start scanning like a Pro!

Did you know, appendicitis is one of the most common surgical emergencies. Despite this, some data suggests that appendicitis is missed in 3.8% to 15% of children and 5.9% to 23.5% of adults in ED visits. Appendicitis is difficult to diagnose due to the early nonspecific generalized symptoms (anorexia, generalized pain, nausea, diarrhea or constipation). We can use point of care ultrasound (POCUS) to help evaluate your differential diagnosis. One study showed that after only a 20-minute training ED physicians at various levels of experience were able to scan for appendicitis with a specificity of 97.9% and a sensitivity to 42.8%.

Beyond the classic pediatric patient, who else does the SonoPro scan?

Pocus use for appendicitis is one of the leading diagnostic tools in pediatrics for acute appendicitis. In the pediatric population limiting radiation is generally thought to be of utmost importance. The lack of exposure to radiation and small habitus makes ultrasound a great alternative in the pediatric patient. These tips and tricks can be useful in other high risk adult patients, like pregnant women. It is well known that in adults there is often a higher chance of pathology and surgeons are managing the ultimate say on whether more imaging is necessary. However, the use of ultrasound for acute appendicitis may save time, expedite care, lead to quicker consultation, and potentially augment patient satisfaction and improve outcomes. 

How to scan like a Pro:

• There are a few ways to scan for the appendix. To start, we recommend simply asking for the patient to point to where the pain is worst and place the probe directly over that spot. 

•  A simple trick is to have the patient cross their right leg over their left leg; this brings the appendix closer to the abdominal wall. 

• If neither of these work, start to look for visual landmarks to orient yourself: iliac artery and vein, and the psoas muscle. The psoas muscle will be posterior, the iliac artery will be medial and the iliac crest lateral. Many times the appendix may be on top of the iliac artery. ‘Lawn mowing’ the probe up and down in this area may help it come into view.

What to Look For:

•  Try to look for a blind ending tubular structure that is not undergoing peristalsis. When you locate this, turn your probe to view the appendix in short axis and measure the anterior to posterior diameter. In a normal appendix this may be shorter than the lateral measurements as a normal appendix is compressible!

• There are two main criteria for diagnosing appendicitis on ultrasound: 

1. > 6mm*

2. non-compressible 

*Note: Make sure to consider your patient’s age; the criteria may not apply to young children as their appendix may be naturally smaller. Appendix growth typically occurs at 3 to 6 years, therefore in this population you may depend more on secondary findings.

There are many secondary findings that many experts believe may be more useful than the measurements of the appendix itself as this can be very difficult to accurately measure:

What to do next:

Ultrasound for appendicitis is very specific, however not very sensitive. If you see a dilated non-compressible blind ending loop of bowel without peristalsis, you may have identified an appendicitis - call your surgeon, follow recommendations and start antibiotics! If you are uncertain, look for secondary signs of appendicitis as above; if they are found you can increase your suspicion of appendicitis. If these findings are not present, more advanced diagnostic imaging may be required with respect to your clinical suspicion. Consider an MRI in a young patient or CT scan with contrast in an adult for further evaluation.

Where to Learn More (References)

1. Mahajan P, Basu T, Pai C, et al. Factors Associated With Potentially Missed Diagnosis of Appendicitis in the Emergency Department. JAMA Network Open. 2020;3(3):e200612. doi:10.1001/jamanetworkopen.2020.0612.

2. Y Ravichandran, P Harrison, E Garrow, and JH Chao. Size Matters: Point of care Ultrasound in Pediatric Appendicitis. Pediatric Emergency Care. 2016; 32: 815-816.

3. Ma, John, et al. Ma and Mateer's Emergency Ultrasound. McGraw-Hill Education, 2020.

4. Macias, Micheal. TPA, The Pocus Atlas. 

5. Availa, Jacob. 5 minute Sono. 

6. US G.E.L. Podcast

7. Nelson, Chiricolo, Raio, Theodoro, Patel, Johnson. Can Emergency Physicians Positively Predict Acute Appendicitis on Focused Right Lower Quadrant Ultrasound?. Annals of Emergency Medicine, 2005; 46: 27-28

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Expert Commentary

Excellent job by Morgan and David on this engaging and informative post summarizing the latest and greatest pro-tips and tricks for POCUS for Appendicitis. POCUS again has been demonstrated to be a helpful adjunct to improve time to diagnosis and treatment when utilized by trained clinicians for appropriate patients. On your next pediatric, pregnant, or otherwise thin “Rule out Appy”, begin the exam by asking the patient to cross their leg to flex the psoas muscle to bring the appendix closer to probe. Have the patient point to the pain to identify where to start. If the appendix is not visualized, then go to McBurney’s point in the axial plane, visualizing the iliac artery & vein to find the nearby appendix. Next, start “lawn mowing” by compressing slowly but with adequate depth to displace bowel gas. Once you see what appears to be an inflamed appendix, trace the structure to verify the blind-ending and hold your probe for a few seconds to confirm the lack of peristalsis. Measure the diameter, then turn on color flow and look for other secondary signs of inflammation. Since the specificity is high, when appendicitis is visualized, call your surgeon, and consider skipping the CT. But remember, since the appendix often “hides” within the bowel the sensitivity is low, so other comprehensive imaging will be needed to reach the correct diagnosis.

John Bailitz, MD

Vice Chair for Academics, Department of Emergency Medicine

Professor of Emergency Medicine, Feinberg School of Medicine

Northwestern Memorial Hospital

Shawn Luo, MD

PGY4 Resident Physician

Northwestern University Emergency Medicine

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How To Cite This Post:

[Peer-Reviewed, Web Publication] McCarthy, M. Feiger, D. (2021, Nov 22). Sono Pro Tips and Tricks for Acute Appendicitis. [NUEM Blog. Expert Commentary by Luo, S and Bailitz, J]. Retrieved from http://www.nuemblog.com/blog/sonopro-tips-and-tricks-for-acute-appendicitis

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SonoPro Tips and Tricks for Acute Cholecystitis

Written by: John Li, MD (NUEM ‘24) Edited by: Amanda Randolph (NUEM ‘21) Expert Commentary by: John Bailitz, MD & Mike Macias, MD

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SonoPro Tips and Tricks

Welcome to the NUEM Sono Pro Tips and Tricks Series where Sono Experts team up to take you scanning from good to great for a problem or procedure!

For those new to the probe, we recommend first reviewing the basics in the incredible FOAMed Introduction to Bedside Ultrasound Book and 5 Minute Sono. Once you’ve got the basics beat, then read on to learn how to start scanning like a Pro!

Point of care right upper quadrant ultrasound has been shown to be a highly sensitive (82-91%), specific (66-95%), cost effective and efficient modality for emergency medicine physicians to quickly and effectively identify biliary pathology [1-5]. But despite its widespread utility, right upper quadrant ultrasound can often be a technically difficult study for the beginner sonographer, as there are multiple factors that can influence its ease of acquisition ranging from patient body habitus to bowel gas shadowing, and sonographer experience has been shown to influence its efficacy [1, 6-7].

Beyond the classic patient with right upper quadrant pain, what other scenarios do Sono-Pros use right upper quadrant ultrasound?

1. Epigastric abdominal pain being “diagnosed” and even over treated as GERD. Pick up the probe in the symptomatic patient taking their PPI, EGD negative, or already treated for H. pylori

2. Unexplained right shoulder or back pain. 

3. Colicky pain in the right flank but no urinary findings of nephrolithiasis. 

4. My gallstones are back! But my gallbladder is gone. Look for choledocholithiasis.

5. Chronically ill elderly or immunosuppressed patients with unexplained fever or sepsis. 

SonoPro Tips - How to scan like a Pro

Always Start Smart: To Fail to Prepare is to Prepare to Fail whether in ED POCUS or ED Thoracotomy.

1. Start with the patient in either the left lateral decubitus position or supine with the bed at approximately 30 degrees.

2. Let the patient know “I’ll be asking you throughout this brief exam to take medium to deep breaths and hold for 5 sec, then automatically breathe out.” 

Still not not getting great views? 

1. Scan between the ribs to use the liver as an acoustic window and avoid bowel gas. Switch to a small footprint phased array probe if needed. 

   • Not sure which intercostal space to use? Try about 7 centimeters to the right of the patient’s xiphoid process!

2. Ask the patient to position their arms above their head to open the intercostal space. 

3. Ask the patients to bend their knees to relax the abdominal muscles.

4. In young, thin patients, the gallbladder may be more anterior and superior-- if you are scanning subcostally, try flattening out the probe even more!

Even a Small Pain in the Neck can be a Big Problem!

1. Don’t forget the neck. There is a reason the gallbladder was so nicely distended and  easy to find. Be sure to scan carefully in two orthogonal planes to pick up subtle stones in the neck of the gallbladder!

   • If there is a lot of nearby bowel gas, tell your tech to look for these stones if your surgeons require a confirmatory comprehensive radiology ultrasound before operating. 

View fullsize

In this GIF, you can see a long-axis view of the gallbladder. When you are initially looking at the body and the fundus of the gallbladder, there are no clear shadowing stones. However, as the sonographer fans to the neck of the gallbladder, they can visualize multiple stones, which are casting shadows posteriorly. Image courtesy of the POCUS Atlas.

SonoPro Tips - Pro Pick Ups!

1. Is that a stone or is that something else in the gallbladder? Roll the patient and see if the “stone” moves! 

   • If the stone in the fundus or body moves, then it’s more likely a mobile stone. 

   • If it doesn’t move, then consider a polyp or a malignancy. Polyps or malignancies generally are non-shadowing while stones are shadowing!

   • Impacted, “non-mobile” Neck Stone = Big Problem and likely to progress to acute cholecystitis. 

2. What’s causing that shadow?

   • Stones shadow posteriorly. 

   • Edges shadow on the sides. Edge artifact results when ultrasound beams scatter passing by a smooth-walled structure, creating an anechoic stripe that could be confused with true shadowing!

3. What if the entire gallbladder is casting a shadow?

   • Think about a gallbladder FULL of stones! This will cause only the most anterior stones to show up on ultrasound.

View fullsize

Here, on the right side of the screen you see a cross section of the gallbladder that has a large stone in it-- this is casting a shadow so you do not see the posterior wall of the gallbladder at all. This is called the wall echo sign-- where you will only see the most anterior surface of the stone. Image courtesy of the POCUS Atlas.

4. What are some of those pesky mimics of acute cholecystitis?

• Think about hepatic pathologies! Acute hepatitis can cause a clinical Murphy’s sign. You can also have patients who present similarly when they have a congestive hepatopathy from their CHF. Even cirrhotic patients can present with a tender RUQ!

View fullsize

Here, you can see a dilated gallbladder with a thickened anterior wall and a small amount of pericholecystic fluid, all of which are consistent with acute cholecystitis. Image courtesy of the POCUS Atlas.

View fullsize

In this still image, you can see a thickened gallbladder wall (although be sure to measure the anterior wall, as the posterior wall can be thickened due to posterior acoustic enhancement!) and a small amount of pericholecystic fluid.  Image courtesy of the POCUS Atlas.

View fullsize

Here, you can see a dilated gallbladder with an obstructing stone in the neck of the gallbladder. Image courtesy of the POCUS Atlas.

SonoPro Tips - What the Pro’s Do Next!

View fullsize

Infographic courtesy of Justin Seltzer, MD

1. If you see nonshadowing masses in the gallbladder:

   • Measure it! If the polyp is >1cm, then there’s a ~50% chance that this could be malignant, so be sure to refer these patients for additional imaging and close follow up. 

2. What if you’re hoping to be really thorough and get a beautiful image of the CBD, but despite your best efforts, you cannot find it?

   • Draw some LFTs! A number of our emergency medicine colleagues, including Becker et. al and Lahham et. al, have done studies on this and it has been shown to be very unlikely that the CBD will be pathologically dilated in the setting of normal LFTs. On the flip side, if the LFTs appear cholestatic in nature, that’s another indication for a right upper quadrant ultrasound! [9-10]

SonoPro Tips - Where to Learn More

Do you want to see more pathologic images that you may see when you are doing a right upper quadrant ultrasound? Be sure to check out The Pocus Atlas by our expert editor Dr. Macias! It’s a great resource that also shows some of the rarer etiologies of gallbladder pathology, such as emphysematous cholecystitis or choledocholithiasis.

If you’re interested in looking at some of the evidence behind the right upper quadrant ultrasound, be sure to check out the evidence atlas here as well!

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Expert Commentary

Thank you to NWEM1 John Li for bringing this great idea for a NUEM Blog Series to life. And another thanks to NUEM Blog Founder Mike Macias for his help on both content and graphics!

This new series is intended to push your Sono skills from just good, to really great. We will not rehash the basics. There are already abundant great resources available that we are truly thankful for and utilize everyday. But instead, we will share SonoPro Tips to help you more quickly master challenging POCUS applications and procedures. 

And there is no place better to start than Acute Cholecystitis. This is a great differentiator between the average and the expert clinician sonographer. As John outlines, start smart by expanding your indications and positioning your patient properly from the get go. Then breath, not you, the patient. Breath and hold again and again to bring the gallbladder and even difficult to discern pathology into clear view. Go beyond getting stones, and work to pick up, and explain other pathologies, as well as the bile ducts when needed.  

Thanks again John and Mike! Looking forward to the next post in this new series...

John Bailitz, MD

Vice Chair for Academics, Department of Emergency Medicine

Professor of Emergency Medicine, Feinberg School of Medicine

Northwestern Memorial Hospital

Michael Macias, MD

Global Ultrasound Director, Emergent Medical Associates

Clinical Ultrasound Director, SoCal MEC Residency Programs

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How To Cite This Post:

[Peer-Reviewed, Web Publication] Li, J. Randolph, A. (20201 Mar 22). SonoPro Tips and Tricks for Acute Cholecystitis. [NUEM Blog. Expert Commentary by Bailitz, J. Macias, M]. Retrieved from http://www.nuemblog.com/blog/sonopro-tips-and-tricks-for-acute-cholecystitis

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References

1. Jain A, Mehta N, Secko M, Schechter J, Papanagnou D, Pandya S, Sinert R. History, Physical Examination, Laboratory Testing, and Emergency Department Ultrasonography for the Diagnosis of Acute Cholecystitis. Acad Emerg Med. 2017 Mar;24(3):281-297. doi: 10.1111/acem.13132. PMID: 27862628.

2. Miller, Adam H., et al. “ED Ultrasound in Hepatobiliary Disease.” The Journal of Emergency Medicine, vol. 30, no. 1, 2006, pp. 69–74., doi:10.1016/j.jemermed.2005.03.017. 

3. Shekarchi B, Hejripour Rafsanjani SZ, Shekar Riz Fomani N, Chahardoli M. Emergency Department Bedside Ultrasonography for Diagnosis of Acute Cholecystitis; a Diagnostic Accuracy Study. Emerg (Tehran). 2018;6(1):e11. Epub 2018 Jan 20. PMID: 29503836; PMCID: PMC5827043.

4. American College of Emergency Physicians: Emergency Ultrasound Imaging Criteria Compendium. Oct. 2014, www.acep.org/globalassets/new-pdfs/policy-statements/emergency-ultrasound-imaging-criteria-compendium.pdf. 

5. Hilsden R, Leeper R, Koichopolos J, et al. Point-of-care biliary ultrasound in the emergency department (BUSED): implications for surgical referral and emergency department wait times. Trauma Surg Acute Care Open. 2018;3(1):e000164. Published 2018 Jul 30. doi:10.1136/tsaco-2018-000164

6. Ma, John, et al. Ma and Mateer's Emergency Ultrasound. McGraw-Hill Education, 2020. 

7. Mallin, Mike, and Matthew Dawson. Introduction to Bedside Ultrasound: Volume 2. Emergency Ultrasound Solutions, 2013. 

8. Macias, Michael. TPA, www.thepocusatlas.com/. 

9. Becker BA, Chin E, Mervis E, Anderson CL, Oshita MH, Fox JC. Emergency biliary sonography: utility of common bile duct measurement in the diagnosis of cholecystitis and choledocholithiasis. J Emerg Med. 2014 Jan;46(1):54-60. doi: 10.1016/j.jemermed.2013.03.024. Epub 2013 Oct 11. PMID: 24126067.

10. Lahham S, Becker BA, Gari A, Bunch S, Alvarado M, Anderson CL, Viquez E, Spann SC, Fox JC. Utility of common bile duct measurement in ED point of care ultrasound: A prospective study. Am J Emerg Med. 2018 Jun;36(6):962-966. doi: 10.1016/j.ajem.2017.10.064. Epub 2017 Nov 20. PMID: 29162442.