Author: UCSD Ultrasound

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Case 49: ARDS

Kayhon Rabbani

A 22 year old male who has no past medical history presented with a 3 day history of viral URI-like symptoms with sore throat, dry cough, shortness of breath, and dyspnea on exertion. The patient was an active marine recruit with many other members in his company being sick during this time. Shortly prior to arrival, the patient became unable to walk short flights of steps without becoming short of breath. The patient otherwise had no respiratory or cardiac history. He had no family history of sudden cardiac death or early MI. The patient denied fevers, chills, chest pain, pleuritic chest pain, positional chest pain, abdominal pain, flank pain, dysuria, hematuria, diarrhea, or any other associated symptoms.

Vitals: BP 87/56 | Pulse 96  | Temp 98.6 °F (37 °C)  | Resp 28 | SpO2 92%

On physical examination, the patient was alert and in acute distress. Patient presented with tachycardia, hypotension, hypoxia, and tachypnea. Mucous membranes were dry. Respiratory exam revealed decreased air movement, breath sounds, and faint crackles in the right lower lung field.

A bedside echocardiogram was performed.

Figure 1: POCUS echocardiogram in 4 chamber apical view demonstrating a small pericardial effusion.

Figure 2: POCUS lung exam revealed bilateral B lines anterosuperior aspects of the lungs.

Figure 3: Lung consolidation and pleural effusion demonstrating positive "spine sign."

The patient was initially stable but desaturated upon position change. The patient was persistently hypoxic with significant work of breathing on BiPAP before escalating to intubation, remaining persistently hypoxic in the mid 80s post intubation on a ventilator.

Discussion

Acute respiratory distress syndrome (ARDS) is a severe form of acute respiratory failure characterized by rapid onset of widespread inflammation in the lungs. It is defined by the Berlin criteria, which include acute onset within one week of a known clinical insult, bilateral opacities on chest imaging not fully explained by cardiac failure or fluid overload, and severe hypoxemia with a PaO2/FiO2 ratio of less than 300 mmHg.[1-3]

Common differential diagnoses for ARDS include cardiogenic pulmonary edema, pneumonia, and pulmonary embolism. Cardiogenic pulmonary edema can be differentiated by the presence of signs of fluid overload and cardiac dysfunction, often confirmed by echocardiography. Pneumonia may present with localized infiltrates and clinical signs of infection, while pulmonary embolism typically presents with sudden onset dyspnea, pleuritic chest pain, and may be confirmed by imaging studies such as CT pulmonary angiography.[1][4-5]

On physical examination, patients with ARDS often present with tachypnea, dyspnea, and diffuse crackles on auscultation. Hypoxemia is a hallmark, and patients may exhibit signs of respiratory distress such as use of accessory muscles and cyanosis. Imaging studies, particularly chest radiography, typically reveal bilateral alveolar infiltrates. Computed tomography (CT) scans can provide more detailed images, showing patchy or diffuse ground-glass opacities and consolidations.[1-2][6]

Point-of-care ultrasound (POCUS) is a valuable tool in the diagnosis and management of ARDS. Lung ultrasound findings in ARDS include the presence of multiple B-lines (indicating interstitial syndrome), spared areas, pleural line thickening, and subpleural consolidations. Cardiac ultrasound can help differentiate ARDS from cardiogenic pulmonary edema by assessing left ventricular function and the presence of pleural effusions.[7] Combining lung and cardiac ultrasound can enhance diagnostic accuracy and guide management decisions in critically ill patients with acute hypoxemic respiratory failure.[7]

References

  1. Saguil, A., & Fargo, M. V. (2020). Acute Respiratory Distress Syndrome: Diagnosis and Management. American family physician, 101(12), 730–738.
  2. Meyer, N. J., Gattinoni, L., & Calfee, C. S. (2021). Acute respiratory distress syndrome. Lancet (London, England), 398(10300), 622–637. https://doi.org/10.1016/S0140-6736(21)00439-6
  3. Matthay, M. A., Zemans, R. L., Zimmerman, G. A., Arabi, Y. M., Beitler, J. R., Mercat, A., Herridge, M., Randolph, A. G., & Calfee, C. S. (2019). Acute respiratory distress syndrome. Nature reviews. Disease primers, 5(1), 18. https://doi.org/10.1038/s41572-019-0069-0
  4. Papazian, L., Calfee, C. S., Chiumello, D., Luyt, C. E., Meyer, N. J., Sekiguchi, H., Matthay, M. A., & Meduri, G. U. (2016). Diagnostic workup for ARDS patients. Intensive care medicine, 42(5), 674–685. https://doi.org/10.1007/s00134-016-4324-5
  5. Sekiguchi, H., Schenck, L. A., Horie, R., Suzuki, J., Lee, E. H., McMenomy, B. P., Chen, T. E., Lekah, A., Mankad, S. V., & Gajic, O. (2015). Critical care ultrasonography differentiates ARDS, pulmonary edema, and other causes in the early course of acute hypoxemic respiratory failure. Chest, 148(4), 912–918. https://doi.org/10.1378/chest.15-0341
  6. Zompatori, M., Ciccarese, F., & Fasano, L. (2014). Overview of current lung imaging in acute respiratory distress syndrome. European respiratory review : an official journal of the European Respiratory Society, 23(134), 519–530. https://doi.org/10.1183/09059180.00001314
  7. Corradi, F., Brusasco, C., & Pelosi, P. (2014). Chest ultrasound in acute respiratory distress syndrome. Current opinion in critical care, 20(1), 98–103. https://doi.org/10.1097/MCC.0000000000000042
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Case 48: The Gut Feeling Was Right

Kanchi Mehta

A 38yo male with history of diverticulitis complicated by sepsis presented to the ED with lower quadrant abdominal pain. He noted that the pain started 2 weeks ago and became worse. He reported normal bowel movements in the morning, denied fever/chills, nausea, vomiting, or genitourinary symptoms. A recent colonoscopy was notable for moderate sigmoid diverticulosis and a 4mm sessile sigmoid polyp that was resected.

Past medical history: Diverticulitis, ADHD, eczema, insomnia, loose stools

No past surgical history.

Vitals: BP 107/65 | Pulse 73 | Temp 98 °F (36.7 °C) | Resp 18 | BMI 25.35 kg/m²

A bedside ultrasound was performed, and the following image was obtained:

Figure 1: Diverticula with bowel wall edema

Uncomplicated acute diverticulitis characteristics on ultrasound are:

  • thickened bowel wall >5mm
  • presence of diverticula with focal outpouching or bowel wall discontinuity
  • noncompressible pericolic fat inflammation with hyperechogenic halo around bowel serosa
  • sonographic tenderness with compression

Outcome:

General surgery was consulted for possible surgical evaluation, which was deferred after findings on CT noted to be non-surgical. Patient was sent home with ciprofloxacin 500mg BID for 7 days and metronidazole 500mg TID for 7 days. Patient was also educated on return precautions.

References:

  1. Nazerian P, Gigli C, Donnarumma E, et al. Diagnostic accuracy of point-of-care ultrasound integrated into clinical examination for acute diverticulitis: a prospective multicenter study. Ultraschall der Med 2021;42(6):614–22. English.
  2. Cohen A, Li T, Stankard B, et al. A prospective evaluation of point of care ultrasonographic diagnosis of diverticulitis in the emergency department. Ann Emerg Med 2020;76(6):757–66.
  3. Damewood, Sara et al. “Gastrointestinal and Biliary Point-of-Care Ultrasound.” Emergency medicine clinics of North America vol. 42,4 (2024): 773-790. doi:10.1016/j.emc.2024.05.006
  4. https://www.ultrasoundcases.info/cases/abdomen-and-retroperitoneum/gastrointestinal-tract/diverticulosis-and-diverticulitis/
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Case 47: Abdominal Wall Perforation

Cloie June Chiong

A 37 year old male with a past medical history of ulcerative colitis, now status-post total abdominal colectomy with a creation of end ileostomy, left-sided ureteral lysis due to retroperitoneal fibrosis, robotic-assisted proctectomy with creation of an ileoanal pouch and diverting loop ileostomy, extensive lysis of adhesions and right-sided ureterolysis, and ileostomy takedown in 2024 presents to the ED with diffuse abdominal pain that began this morning and sweats beginning last night. The pain was 4/10 with rest, 7/10 with standing, and 8/10 with ambulation. The pain radiated to the right shoulder this morning while lying in bed. He denied nausea and vomiting. He endorsed intermittent testicular pain, reduced oral intake, and decreased voids, but urinated and defecated without pain. Did not report any abnormal concerns with stool input through anastomosis.

Vitals: BP: 122/78 | Pulse: 78 | Temp: 98.6°F | Resp: 16 | SpO2: 100%

Physical Exam showed a soft, flat, non-distended abdomen. A surgical scar was present. There was generalized abdominal tenderness and guarding throughout the abdomen with palpation, without rebound or rigidity. He had tenderness in the lower quadrants > upper quadrants, left > right. There was no hernia present. The remainder of the physical exam was unremarkable.

Labs: WBC 16.9

A bedside ultrasound was performed on the abdomen:

Figure 1: Pneumoperitoneum

Figure 2: Pouchitis

Discussion:

Pneumoperitoneum, a critical condition marked by the presence of free air in the abdominal cavity, typically arises from a perforated hollow viscus and is a rare yet serious cause of acute abdominal pain1,2. This condition requires immediate surgical intervention due to its potential for high mortality. Detecting serious conditions based on abdominal pain alone during physical examinations is challenging due to low sensitivity. Differential diagnoses for acute abdominal pain may include inflammatory bowel disease complications, intra-abdominal abscesses, perforations, bowel obstructions, mesenteric ischemia, and pancreatitis.

While abdominal X-ray and computed tomography of the abdomen are considered as more conventional standards for imaging, ultrasound also serves as a rapid, radiation-free diagnostic tool for detecting gastrointestinal perforations3. The diagnostic performance of ultrasonography for pneumoperitoneum has shown to have a sensitivity of 93%, accuracy of 90%, specificity of 64%, and positive predictive value of 97%, versus plain radiography (79%, 77%, 64%, and 96%, respectively)4.

One key ultrasonographic finding in cases of gastrointestinal perforation is the presence of the peritoneal stripe sign, which shows equidistant, horizontal or vertical reverberations posterior to the abdominal wall and can extend to the lower edge of the monitor, creating a striped pattern of alternating dark and light hyperechoic lines. A “comet tail” appearance may also be present as a result of reverberation artifacts caused by pockets of free air, which acts as a barrier to ultrasound waves2,5.

An additional technique used in ultrasound for detecting a pneumoperitoneum is the "shifting phenomenon." This involves repositioning the patient to observe the movement of air and the peritoneal stripe sign within the peritoneal cavity, confirming the presence of free air6. The "scissors maneuver" further confirms this technique by placing a linear probe in the right epigastric region without abdominal compression; reverberation artifacts are observed and manipulated by pressing and releasing the caudal end of the probe, showing movement of the free air and reverberation artifacts away from the anterior liver5.

The use of ultrasound not only confirmed the presence of pneumoperitoneum, but also allowed for immediate surgical intervention, underscoring its high sensitivity and the crucial impact of rapid assessment capabilities in emergency settings. Point-of care ultrasound should be considered as a potential first-line form of diagnostic imaging for abdominal perforation.

References:

  1. Nazerian, P., Tozzetti, C., Vanni, S. et al. Accuracy of abdominal ultrasound for the diagnosis of pneumoperitoneum in patients with acute abdominal pain: a pilot study. Crit Ultrasound J 7, 15 (2015). https://doi.org/10.1186/s13089-015-0032-6
  2. Chao, A., Gharahbaghian, L., & Perera, P. (2015). Diagnosis of pneumoperitoneum with bedside ultrasound. The western journal of emergency medicine, 16(2), 302. https://doi.org/10.5811/westjem.2014.12.24945
  3. Jiang L, Wu J, Feng X. The value of ultrasound in diagnosis of pneumoperitoneum in emergent or critical conditions: A meta-analysis. Hong Kong Journal of Emergency Medicine. 2019;26(2):111-117. doi:10.1177/1024907918805668
  4. Bacci, M., Kushwaha, R., Cabrera, G., & Kalivoda, E. J. (2020). Point-of-Care Ultrasound Diagnosis of Pneumoperitoneum in the Emergency Department. Cureus, 12(6), e8503. https://doi.org/10.7759/cureus.8503
  5. Taylor, M.A., Merritt, C.H., Riddle, P.J. et al. Diagnosis at gut point: rapid identification of pneumoperitoneum via point-of-care ultrasound. Ultrasound J 12, 52 (2020). https://doi.org/10.1186/s13089-020-00195-2
  6. Yum, J., Hoffman, T., & Naraghi, L. (2021). Timely Diagnosis of Pneumoperitoneum by Point-of-care Ultrasound in the Emergency Department: A Case Series. Clinical practice and cases in emergency medicine, 5(4), 377–380. https://doi.org/10.5811/cpcem.2021.4.52139
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Case 46: Skin and Soft Tissue Infection

Alma Fregoso Leyva

73 year old male with a past medical history of coronary artery disease, congestive heart failure, COPD, pulmonary fibrosis on 5L NC, and left lower extremity prosthetic joint infection s/p total femur replacement presented via EMS with 3 days of worsening left lower leg pain and swelling. He reported pain around the left lower leg down to the foot. His symptoms were associated with chills and fatigue. He reported compliance with Eliquis. 

Vitals: BP 92/80, Pulse 100, Temp 98.1 F, RR 11, SpO2 93% on 5L NC 

Physical Exam:
- General: A&O x4
- Cardiac: RRR
- Lungs: CTAB w/o increased work of breathing while on 5L NC
- Extremities: 1+ non -pitting edema of right lower extremity, 2+ at left lower extremity. Intact sensation to light touch at left lower extremity, able to wiggle all toes, diffuse swelling below the left knee and down to the foot L>R, with diffuse tenderness. No crepitus or pain out of proportion. Erythema over anterior shin, scattered skin excoriations of bilateral lower legs. 

Bedside ultrasound was performed and the following images were obtained: 

Figure 1: Left popliteal vein.

Figure 2: Collapsed left popliteal vein.

Figure 3: Cobblestone appearance of the left lower leg.

DISCUSSION

Concern for deep vein thrombosis (DVT) was present given asymmetric edema and pain, Point-of-care ultrasound (POCUS) was performed and DVT was ruled out. Ultrasound of the lower leg also demonstrated “cobblestoning”. Left lower extremity and peri-prosthetic fluid collection found on CT. The patient was started on antibiotics for the SSTI. 

POCUS has become a valuable tool in the Emergency Department given its availability, portability, lack or radiation and tolerability by patients. Skin and soft tissue infections (SSTIs) are primarily diagnosed clinically based on history and physical exam, but imaging is used to assess beyond superficial tissue. Clinically SSTIs are characterized by symptoms such as erythema, swelling, warmth, pain, fever, chills and leukocytosis, especially in patients with predisposing factors. The primary sonographic finding in cellulitis is referred to “cobblestone” appearance, this appears as fluid collects in the subcutaneous tissue. However, this pattern is not unique to cellulitis and may be seen in other medical conditions. POCUS is valuable for diagnosis abscesses, guiding drainage and plays a crucial role in evaluating severe soft-tissue infections such as necrotizing fasciitis. When POCUS is performed prior to incision and drainage, it can help prevent invasive procedures over vascular or neoplastic lesions that can resemble abscesses on physical exam. Studies have shown that the use of POCUS is more accurate for diagnosing abscesses than clinical examination alone. 

REFERENCES

1. Hazra, Darpanarayan; Elshehry, Ashraf. Cobblestone Appearance in Point-of-Care Ultrasonography (POCUS). Current Medical Issues 22(1):p 54-55, Jan–Mar 2024. | DOI: 10.4103/cmi.cmi_128_23 
2. Koppa BM, Kelly CT. Point-of-care ultrasound in skin and soft tissue infections. J Hosp Med. 2024 Oct;19(10):938-944. doi: 10.1002/jhm.13467. Epub 2024 Jul 31. PMID: 39082276. 
3. Subramaniam, Sathyaseelan, et al. "Point‐of‐care ultrasound for diagnosis of abscess in skin and soft tissue infections." Academic Emergency Medicine 23.11 (2016): 1298-1306. 

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Case 45: Distal Both Bone Fracture

Teini Elisara

Case

An 82 year old female with a past medical history of anemia of chronic disease, breast cancer, diabetes mellitus, hypertension, osteoporosis, rectal adenocarcinoma, scleroderma with pulmonary involvement, and systemic lupus erythematosus presented to the emergency department after a mechanical fall the night prior. She was getting into bed when she tripped and fell on the left side of her body landing on her left arm and hitting the side of her head on the floor. Patient endorsed severe pain to her left wrist.

Vitals: BP 162/64 | Pulse 67 | Temp 98 °F (36.7 °C) | Resp 16 | Wt 53 kg (116 lb 13.5 oz) | SpO2 98% | BMI 22.08 kg/m²

On physical exam of the left wrist, there was significant swelling and overlying bruising. She was unable to supinate due to severe pain. Sensation was intact throughout the hand and wrist. The wrist did not appear grossly displaced laterally or medially. She had decreased range of motion secondary to pain with sensation intact and was able to move her digits. There were no open wounds.

A bedside ultrasound was performed on the patient’s distal forearm, the following images were obtained:

Figure 1: Left distal ulna fracture.

Figure 2: Left distal radius fracture

The joint capsule was visualized and negative for signs of effusion. The right wrist also scanned for anatomy comparison.

Discussion

In this case, we identified fractures in both the distal radius and ulnar styloid of our patient. We were able to identify fractures quickly and with minimal discomfort to the patient. Left distal radius and ulnar styloid fractures were confirmed by two-plane x-ray.

Cortical fractures are a common presentation to the emergency department, with distal forearm fractures being amongst the most common in both adult and pediatric populations. Wrist fracture prevalence in the United States is 12% in adults over the age of 50, with significant increases over the last 20 years [1,2]. As X-ray is the gold standard for diagnosing fractures, ultrasound is not typically thought of as an option for identification. However, it is a possible alternative for fracture identification in the emergency department, with high specificity and sensitivity [3]. In addition, ultrasound can be used to assess the healing phases of fracture using grayscale and color doppler [4]. With increased prevalence and use of ultrasound, it is a quick alternative for patients where reduction of exposure to ionizing radiation is preferred, such as pediatrics or pregnancy.

References

  1. Ye J, Li Q, Nie J. Prevalence, Characteristics, and Associated Risk Factors of Wrist Fractures in Americans Above 50: The Cross-Sectional NHANES Study. Front Endocrinol (Lausanne). 2022 Apr 25;13:800129. doi: 10.3389/fendo.2022.800129. PMID: 35547001; PMCID: PMC9082306.
  2. Xu B, Radojčić MR, Anderson DB, Shi B, Yao L, Chen Y, Feng S, Lee JH, Chen L. Trends in prevalence of fractures among adults in the United States, 1999-2020: a population-based study. Int J Surg. 2024 Feb 1;110(2):721-732. doi: 10.1097/JS9.0000000000000883. PMID: 37921645; PMCID:PMC10871608.
  3. Douma-den Hamer D, Blanker MH, Edens MA, Buijteweg LN, Boomsma MF, van Helden SH, Mauritz GJ. Ultrasound for Distal Forearm Fracture: A Systematic Review and Diagnostic Meta-Analysis. PLoS One. 2016 May 19;11(5):e0155659. doi: 10.1371/journal.pone.0155659. PMID: 27196439; PMCID: PMC4873261.
  4. Cocco G, Ricci V, Villani M, Delli Pizzi A, Izzi J, Mastandrea M, Boccatonda A, Naňka O, Corvino A, Caulo M, Vecchiet J. Ultrasound imaging of bone fractures. Insights Imaging. 2022 Dec 13;13(1):189. doi: 10.1186/s13244-022-01335-z. PMID: 36512142; PMCID: PMC9748005.
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Case 44: Interscalene Nerve Block for Shoulder Dislocation

Josh Gieschen

Case:

32yo male with no PMH who presents following a fall down the stairs with no head strike or loss of consciousness. He endorses left shoulder pain and inability to range his left shoulder. He has never dislocated his shoulder before. His pain is 8/10 and limited to the L shoulder, worse with motion or palpation.

Vitals:  Temp 97.6 °F | HR 87 | RR 18 | BP 119/76 | SPo2 100% on RA

Physical Exam: L arm held internally rotated, flexed, and guarded closely to torso. An obvious step-off deformity was seen directly lateral to glenoid with increased prominence of the shoulder anteriorly. Range of motion was limited severely by pain. The surrounding musculature was tense and tender to palpation. Distal sensation and pulses were intact in the bilateral upper extremities. The remainder of the physical exam was unremarkable.

The patient required hydromorphone 1mg IM during his initial evaluation for pain control.  He was noted to have large muscle bulk, with anticipated difficulty with reduction.  He was given 1mg lorazepam IM for anxiolysis and consented for an interscalene nerve block.  The nerve block was done under ultrasound guidance.

Figure 1: Needle-in-plane posterior approach through the middle scalene to the interscalene nerve bundle.

Figure 2: Lidocaine surrounds the interscalene nerve bundle.

The patient’s shoulder was subsequently reduced using Kocher’s method.

Discussion:

In this case, the patient’s shoulder dislocation was clinically evident. POCUS was primarily employed for interscalene nerve block. Given the patient’s high muscle mass, it was anticipated that reduction without targeted analgesia and anxiolysis would be challenging and highly uncomfortable. US guidance allowed isolation of a nerve bundle that would have otherwise been difficult if not impossible to target on its own, and the resulting relaxation and pain improvement allowed reduction to proceed with ease.

Interscalene blocks are commonly used for procedures and pathology of the shoulder and upper arm. They are not recommended for indications involving the hand as the inferior trunk of the brachial plexus is often spared, leading to sparing of the ulnar nerve (1).  Possible complications include phrenic nerve paralysis or Horner’s syndrome, though these are relatively rare. Because of these possible complications, interscalene blocks are relatively contraindicated in patients with respiratory insufficiency (2). Overall, interscalene blocks are a highly useful tool for analgesia and relaxation of the shoulder and upper arm and can facilitate procedures in the ED

References:

1. Operater. “Ultrasound-Guided Interscalene Brachial Plexus Nerve Block.” NYSORA, 1 Nov. 2024, www.nysora.com/techniques/upper-extremity/intescalene/ultrasound-guided-interscalene-brachial-plexus-block/.

2. Zisquit J, Nedeff N. Interscalene Block. [Updated 2022 Sep 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK519491/

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Case 43: Shortness of Breath

Molly Chou

An 83-year-old male presented to our emergency department with shortness of breath. He woke up that morning with symptoms and called EMS. On arrival, the patient was alert and oriented with SpO2 90% on room air. The patient had a recent admission for right middle and lower lobe pneumonia. He also reported a history of heart failure with mildly reduced ejection fraction, coronary artery disease, and chronic kidney disease.

Vitals: BP 122/71, HR 92, RR 30, T 98.8F, spO2 90% on room air, 99% on 4LNC

Exam: Normal heart sounds, tachypnea, rhonchi in bilateral lower lobes, non-tender abdomen, >4mm pitting lower extremity edema

Labs: Cr 2.23 (from 1.98), BNPP 34,591 (from 19,366), WBC 31

EKG: new left bundle branch block

CXR: pulmonary edema, bilateral pleural effusions, and opacities that may represent atelectasis, though cannot rule out pneumonia or aspiration.

A bedside ultrasound was performed:

Figure 1: Right-sided pleural effusion, atelectasis, and pneumonia in seen right lower lobe

Figure 2A: During exhalation. Left-sided pleural effusion, atelectasis. 2B: During inhalation. Pneumonia becomes more visible as air fills alveoli adjacent to consolidated lung tissue (also known as “dynamic air bronchogram”)

Discussion: Bedside ultrasound demonstrated persistent pneumonia as a likely contributor to his shortness of breath. While other clinical indicators directed the diagnosis toward acute on chronic heart failure, POCUS was instrumental in also identifying persistent pneumonia. The patient was ultimately started on antibiotics and admitted to Cardiology for pneumonia and diuresis.

Learning points:

  • Pneumonia is among the leading causes of hospitalization, and it can be detected on ultrasound if the pleural line is involved, which is in about 99% of cases.
  • Ultrasound can detect inflammation and lung-tissue thickening of lobar pneumonias and consolidations. Interstitial pneumonias more often manifest as B-lines or white lung areas. Complications such as empyema and lung abscess can also be detected [1].
  • POCUS is highly sensitive (estimated around 93%) and specific (estimated around 98%) for pneumonia, particularly if done by a skilled sonographer [2,3].
  • Classic ultrasound findings:
    • “Hepatization” of lung parenchyma, when multiple hypoechoic areas give the tissue a “liver-like” or “spleen-like” appearance.
    • “Shred sign” (Figure 1), when a clear margin can be detected separating a consolidation with aerated parenchyma.
    • Air bronchograms (hyperechoic, linear punctate spots) can be detected within a consolidation in over 90% of pneumonia patients, though they are non-specific, as they may indicate any form of airway obstruction [1].
      • However, “dynamic air bronchograms” (Figure 2) where air-filled bronchograms move with respiration, are highly specific (94%) to pneumonia and have a high positive predictive value (97%) when seen [4]. An example can be seen below [5]:

References:

  1. Boccatonda A, Cocco G, D'Ardes D, et al. Infectious Pneumonia and Lung Ultrasound: A Review. J Clin Med. 2023;12(4):1402. Published 2023 Feb 10. doi:10.3390/jcm12041402
  2. Reissig A, Copetti R, Mathis G, et al. Lung ultrasound in the diagnosis and follow-up of community-acquired pneumonia: a prospective, multicenter, diagnostic accuracy study. Chest. 2012;142(4):965-972. doi:10.1378/chest.12-0364
  3. Chavez MA, Shams N, Ellington LE, et al. Lung ultrasound for the diagnosis of pneumonia in adults: a systematic review and meta-analysis. Respir Res. 2014;15(1):50. Published 2014 Apr 23. doi:10.1186/1465-9921-15-50
  4. Lichtenstein D, Meziere G, Seitz J. The Dynamic Air Bronchogram: A Lung Ultrasound Sign of Alveolar Consolidation Ruling Out Atelectasis. Chest. 2009;135(6):1421-1425. Published 2009 Jan 8. doi:10.1378/chest.08-2281
  5. Hailey Hobbs, MD. Dynamic Air Bronchograms. NephroPOCUS. Published 2019 Jul 1. Accessed 2024 Dec 13.
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Case 42: Nephrolithiasis

Alex Liang, Rachna Subramony

A 48 year old male with past medical history of Crohn’s Disease, cryptogenic cirrhosis, pancytopenia, portal vein thrombosis, Factor V Leiden, and prior history of kidney stones presenting with right sided flank pain, dysuria, and hematuria worsening over the past 4 days. He reports similar symptoms in the past associated with his previous findings of kidney stones. He denies fever, nausea, vomit, diarrhea, chest pain, shortness of breath, or anuria.

Vitals: BP 123/80 mmHg | Pulse: 101 | Temp: 98.5 °F (36.9 °C) | Resp: 20 | Wt: 65.8 kg (145 lb) | SpO2: 97%

On physical examination, the patient is alert and uncomfortable but not in acute distress. Abdominal examination reveals a soft, non-distended abdomen with right flank and right costovertebral angle (CVA) tenderness. The remainder of the physical exam, including cardiac, pulmonary, and neurologic exams, was unremarkable.

A bedside ultrasound was performed on the right kidney.

Figure 1: Several renal calculi in the medullary pyramids of the right kidney. The largest measures approximately 6.8mm in diameter.

Discussion

Nephrolithiasis, commonly referred to as kidney stones, is a prevalent condition with an estimated annual incidence rate of approximately 0.5% to 1% in the general population and a lifetime risk of 10%-15% with higher prevalence among men. Risk factors for nephrolithiasis include dehydration, dietary factors (high sodium or oxalate intake), obesity, metabolic syndrome, and recurrent urinary tract infections1,2.

The differential diagnosis for nephrolithiasis includes conditions that present with acute flank pain, hematuria, and urinary symptoms. Such conditions include pyelonephritis, renal infarction, or ureteropelvic junction obstruction. In this patient, the presentation of acute right flank pain with costovertebral angle tenderness accompanied by dysuria and gross hematuria is strongly indicative of nephrolithiasis.

On physical examination, patients with nephrolithiasis typically present with costovertebral angle tenderness on the affected side with otherwise minimal abdominal findings. The clinician should be attentive of systemic signs such as fever and tachycardia, as they may suggest a concurrent urinary tract infection or obstructive pyelonephritis and require further work up. In this case, the patient presented without fever or systemic signs of infection, supporting a diagnosis of uncomplicated nephrolithiasis.

While non-contrast computed tomography (CT) of the abdomen and pelvis is the gold standard for diagnosing nephrolithiasis, ultrasound remains an asset in the detection of stones with a sensitivity of 54% and specificity of 71%. In some cases, such as in pregnant patients, ultrasound is the preferred modality due to its lack of ionizing radiation. In this case, a renal ultrasound revealed several stones in the medullary pyramids of the right kidney, with the largest measuring 6.8mm in diameter. It is important to note that CT does have higher sensitivity (88%) and lower specificity (58%) compared to ultrasound. Despite this, no evidence has shown that increased CT use is associated with improved patient outcomes when compared to ultrasonography 3.

When performing a point-of-care ultrasound (POCUS) exam for nephrolithiasis, the curvilinear or phased-array transducer should be placed in the flank region along the midaxillary line to obtain longitudinal and transverse views of the kidney. The exam focuses on the identification of hydronephrosis, which appears as anechoic dilation of the renal collecting system, and the detection of renal calculi, which appear as echogenic foci with posterior acoustic shadowing.

Management of nephrolithiasis depends on the size and location. Stones that are less than or equal to 5mm are typically managed conservatively with hydration and analgesia. Medication such as tamsulosin can be given to aid in the expulsion of the stones. Stones that are 10mm or greater, causing significant obstruction, or with concurrent infection or renal impairment often require more invasive measures such as extracorporeal shock wave lithotripsy (ESWL), ureteroscopy with laser lithotripsy, or percutaneous nephrolithotomy 4.

Recurrence of nephrolithiasis is common, with a rate of approximately 50% within 10 years. Patients can decrease this risk with preventative strategies such as dietary modifications (increased fluid uptake, reduced sodium and oxalate consumption) and addressing underlying metabolic abnormalities 4.

References

  1. Pearle MS, Calhoun EA, Curhan GC. Urologic Diseases in America Project: Urolithiasis. J Urol. 2005;173(3):848–857. doi:10.1097/01.ju.0000152082.14384.d7.
  2. Scales CD, Smith AC, Hanley JM, Saigal CS. Prevalence of Kidney Stones in the United States. Eur Urol. 2012;62(1):160–165. doi:10.1016/j.eururo.2012.03.052.
  3. Smith-Bindman R, Aubin C, Bailitz J, et al. Ultrasonography versus Computed Tomography for Suspected Nephrolithiasis. N Engl J Med. 2014;371(12):1100-1110. doi:10.1056/NEJMoa1404446.
  4. Curhan GC. Epidemiology of Stone Disease. Urol Clin North Am. 2007;34(3):287–293. doi:10.1016/j.ucl.2007.05.003.
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Case 41: Abdominal Aortic Aneurysm

Skyler Sloane, Benjamin Supat, Colleen Campbell

An 83-year-old man presented to the emergency department with a chief complaint of acute onset lower abdominal pain radiating to the right groin. The patient reported a history of hypertension, coronary artery disease, and nephrolithiasis. 

Vitals: BP 71/51 | Pulse 84 | Temp 98.0 °F (36.6 °C) | Resp 20 | SpO2 99% on RA 

On physical exam, the patient appeared to be in obvious discomfort. There was diffuse abdominal tenderness though no rebound or guarding was observed.

A bedside FAST exam was performed. What do you see? 

Figures 1-3: This 3-view FAST exam was negative for intra-abdominal free fluid.

Next, we performed an ultrasound of the aorta.

Figure 4: Transverse aorta view. Here we can see a fusiform aneurysm. The hyperechoic vessel wall contains a less dense ring of clot surrounding the anechoic blood in the vessel.

Figure 5: Labeled image showing intramural thrombus.

The patient was given a 1L fluid bolus, 2 ultrasound-guided peripheral 14g IVs, and 2 units of emergency-release blood. The patient also got a CT angiogram which showed a large ruptured fusiform infrarenal abdominal aortic aneurysm measuring 9.2 cm by 6.0 cm with a large hematoma in the right flank and iliac fossa, which explained the patient’s symptom of flank pain. Diffuse moderate atherosclerotic vessel wall changes were also present. The patient underwent emergent endovascular aneurysm repair.

Discussion: 

An abdominal aortic aneurysm (AAA) is defined by the parameter of aortic dilation of 3 cm or greater, measured outer wall to outer wall (1). This risk of developing a AAA increases with age and is more common in males than in females. Primary relationship to a family member who has had an AAA, hypertension, and coronary artery disease are predisposing factors. Smoking and poor lifestyle are also common risk factors (2). 

There are three types of AAAs: fusiform aneurysms, saccular aneurysms, and mycotic aneurysms. Fusiform aneurysms comprise 94% of aneurysms, and they present as bulging or ballooning on all sides of the aorta. Saccular aneurysms are less common and become symptomatic at smaller sizes (on average of 5.5 cm) and present as an outpouching on one side of the aorta. Saccular aneurysms can result from a tear on the tunica media of the aortic wall, due to injury or ulceration. Mycotic aneurysms are formed due to an infection of the vessel wall that can be bacterial, viral, or fungal in nature. They can occur as a complication of endocarditis and have an increased risk of rupture. AAAs are most commonly infrarenal (80%), but some may be pararenal (3,4).

Most patients with AAAs are asymptomatic, and diagnosis is often incidental as a result of imaging with MRI, CT, or ultrasonography. AAAs can present with life-threatening complications such as thrombosis, embolization, and rupture (3). The risk of rupture increases with the size of the aneurysm. A ruptured AAA is a catastrophic medical emergency, and left untreated the mortality approaches 100%. 50% of patients die prior to hospital arrival, and another 25-50% die during surgery.  Most AAAs rupture in the retroperitoneal cavity, creating symptoms of pain, lightheadedness, and a pulsing sensation in the abdomen. Notably, up to 50% of patients with AAAs have aneurysm rupture as their primary presentation of having a AAA, and only some patients are diagnosed prior to a catastrophic event and thus have preventative measures taken (5). 

Due to the emergent need to address potential AAA and AAA ruptures, rapid diagnosis in an emergency setting is necessary. Aortic ultrasound is the primary diagnostic method for diagnosing AAAs or ruptured AAAs in an emergency setting (6). Non-radiologist-performed ultrasound for AAA is estimated to have a sensitivity of 0.975 [95% confidence interval (CI), 0.942-0.992] for AAA detection and a specificity of 0.989 (95% CI, 0.979-0.995), making it an effective diagnostic tool (7). Computed tomography angiogram is also commonly used for diagnosis and surgical planning of AAAs. However, CT is not always feasible in unstable patients (8). 

In this case, point-of-care ultrasound was a vital component in diagnosing this patient. Given a patient presentation concerning for AAA, ultrasound is a rapid and effective method to reach an early diagnosis and expedite treatment. 

References

  1. Hirsch AT, Haskal ZJ, Hertzer NR, et al. ACC/AHA 2005 Circulation. 2006; 113: e463-e654. doi:10.1161/CIRCULATIONAHA.106.174526
  2. Altobelli E, Rapacchietta L, Profeta VF, Fagnano R. Risk Factors for Abdominal Aortic Aneurysm in Population-Based Studies: A Systematic Review and Meta-Analysis. Int J Environ Res Public Health. 2018 Dec 10;15(12):2805. doi: 10.3390/ijerph15122805. PMID: 30544688; PMCID: PMC6313801.
  3. Farber, M. A.; Parodi, F. E. Abdominal Aortic Aneurysms (AAA), 2023, 2023. https://www.merckmanuals.com/professional/cardiovascular-disorders/diseases-of-the-aorta-and-its-branches/abdominal-aortic-aneurysms-aaa.
  4. Aggarwal S, Qamar A, Sharma V, Sharma A. Abdominal aortic aneurysm: A comprehensive review. Exp Clin Cardiol. 2011 Spring;16(1):11-5. PMID: 21523201; PMCID: PMC3076160.
  5. Jeanmonod D, Yelamanchili VS, Jeanmonod R. Abdominal Aortic Aneurysm Rupture. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459176/
  6. Abdominal aortic aneurysm: diagnosis and management. London: National Institute for Health and Care Excellence (NICE); 2020 Mar 19. (NICE Guideline, No. 156.) Available from: https://www.ncbi.nlm.nih.gov/books/NBK556921/
  7. Concannon E, McHugh S, Healy DA, Kavanagh E, Burke P, Clarke Moloney M, Walsh SR. Diagnostic accuracy of non-radiologist performed ultrasound for abdominal aortic aneurysm: systematic review and meta-analysis. Int J Clin Pract. 2014 Sep;68(9):1122-9. doi: 10.1111/ijcp.12453. Epub 2014 May 18. PMID: 24837590.
  8. Moxon JV, Parr A, Emeto TI, Walker P, Norman PE, Golledge J. Diagnosis and monitoring of abdominal aortic aneurysm: current status and future prospects. Curr Probl Cardiol. 2010 Oct;35(10):512-48. doi: 10.1016/j.cpcardiol.2010.08.004. PMID: 20932435; PMCID: PMC3014318.
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Case 40: Rare Ocular Condition Diagnosed by Point-of-Care Ultrasound

Skyler Sloane, Andre Velazquez, Colleen Campbell

A 73-year-old male presented to our emergency department with a chief complaint of new intermittent double vision for the past two weeks. The patient noticed that he saw double when looking at signs on the freeway. These were new symptoms he had not experienced in the past. The patient reported a history of hypertension, hyperlipidemia, and recently diagnosed prostate cancer. The patient also confirmed a history of ocular migraine. The patient denied current headaches, new floaters or flashes, curtains, or clouds in his vision.

Upon arrival, vital signs were: BP 131/91 | Pulse 107 | Temp 97.8 °F (36.6 °C) | SpO2 98% 

Visual acuity: OD 20/20 and OS) 20/20. Pupil light reaction from 3 mm to 2 mm bilaterally. Extraocular movement was full and normal in both eyes. Finger counting was normal in both eyes. The right eye had an intraocular pressure of 13 mmHg and the left eye had an intraocular pressure of 14 mmHg. The bedside anterior segment exam was normal. 

We performed a bedside ultrasound while waiting for an ophthalmology consult and obtained the following images of the left eye. 

Figure 1: Ultrasound of the left eye. 

Figure 2: Labeled ultrasound of the left eye showing asteroid hyalosis (hyperechoic free-floating particles in the vitreous chamber). 

In the obtained images, we see hyperechoic free-floating particles in the vitreous chamber as we scan through the eye. From these images, we reached a diagnosis of asteroid hyalosis. This was later confirmed by ophthalmology through a dilated fundus exam. 

Asteroid hyalosis (AH) is an uncommon degenerative condition that is characterized by the formation of asteroid bodies (AB), comprised of calcium and phospholipids within the vitreous chamber (1). The greatest prominent risk factor is age (2). 

Asteroid hyalosis is benign and asymptomatic in most cases and is not a viable cause for the diplopia that our patient presented with (1). Ophthalmology reported no evidence of strabismus or nystagmus. Additionally, the optic nerve was observed to be sharp and perfused. They postulated that the complaints could be explained by superior oblique myokymia vs retinal hemifield slide. Given the patient’s history of recently diagnosed prostate cancer, brain imaging was recommended to rule out intracranial pathology. Brain imaging revealed no evidence of acute infarct, hemorrhage, or mass. A follow-up with ophthalmology revealed ocular misalignment with a small esotropia in the left eye and a left abduction deficit. The ophthalmologist postulated that this could be due to minor six nerve palsy. This esotropia was found to be the cause of the ocular diplopia.

Asteroid hyalosis can mimic vitreous hemorrhage on ultrasound. Both conditions may show hyperechoic echogenicities swirling in the vitreous chamber in a washing machine or snow globe motion (3). Asteroid particles are composed of calcium linked to phospholipids and often take on an intensely hyperechoic appearance on ultrasound due to their density (2). Conversely, vitreous hemorrhage often appears less hyperechoic than asteroid particles and can have a less granular appearance (4). Differentiating between asteroid hyalosis, a benign and largely asymptomatic condition, and vitreous hemorrhage, a more serious condition that may require emergent intervention is critical. 

Figure 3: Vitreous Hemorrhage: diffuse mobile opacity often referred to as a “snow globe” appearance that is made apparent by side-to-side movement of the eye.

We presented this case to raise awareness of the utility of point-of-care ultrasound in rapidly diagnosing rare ocular diseases. Furthermore, this case is significant because asteroid hyalinosis is a relatively rare disease that is infrequently observed in the emergency department. 

References: 

  1. Scott, D. A. R., Møller-Lorentzen, T. B., Faber, C., Wied, J., Grauslund, J., & Subhi, Y. (2021). Spotlight on Asteroid Hyalosis: A Clinical Perspective. Clinical Ophthalmology, 15, 2537–2544. https://doi.org/10.2147/OPTH.S272333
  2. Duong R, Abou-Samra A, Bogaard JD, Shildkrot Y. Asteroid Hyalosis: An Update on Prevalence, Risk Factors, Emerging Clinical Impact and Management Strategies. Clin Ophthalmol. 2023 Jun 20;17:1739-1754. doi: 10.2147/OPTH.S389111.
  3. Gros EC, Mccafferty LR. Asteroid Hyalosis: A Mimicker of Vitreous Hemorrhage on Point of Care Ultrasound: A Case Report. POCUS J. 2023 Nov 27;8(2):113-115. doi: 10.24908/pocus.v8i2.16391.
  4. De La Hoz Polo M, Torramilans Lluís A, Pozuelo Segura O, Anguera Bosque A, Esmerado Appiani C, Caminal Mitjana JM. Ocular ultrasonography focused on the posterior eye segment: what radiologists should know. (2016) Insights into imaging. 7 (3): 351-64. doi:10.1007/s13244-016-0471-z
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