Month: July 2025

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Case 52: The Role of FAST in Penetrating Thoracoabdominal Injury

Brandon Woo, Elaine Yu

A 28 year old male with unknown past medical history presented to the emergency department with a single gunshot wound sustained to the anterior chest just prior to arrival. He was brought in by family members who reported a witnessed traumatic gunshot wound to the chest by an unreported individual. The patient complained of trouble breathing and was severely agitated in the setting of pain. He required 75 mg IV ketamine for moderate sedation while obtaining vital signs, ultrasound, and intravenous access. The team prepared for urgent intubation in the setting of possible respiratory decompensation and activated massive transfusion protocol.

Vitals: BP 151/81 | Pulse 104 | Temp 97.8º F (36.6ºC) | Resp 27 | Wt 122.2 kg (269 lb 6.4 oz) | SpO2 93%

On physical exam, the patient was in acute distress and diaphoretic, reporting trouble breathing but speaking in full sentences. He was alert and oriented to person, place, and event. Primary trauma assessment: patent airway, rapid shallow breathing, and capillary refill less than 2 seconds. Secondary survey revealed an approximately 1 cm open wound with active bleeding to the subxiphoid region. There were no step-offs or deformities to the spine and no other obvious signs of trauma externally. There were equal breath sounds, and 2+ pulses were present in the radial and posterior tibialis arteries. The remainder of the exam was unremarkable.

A FAST exam was performed to evaluate for free fluid, hemothorax, or pericardial effusion.

Figure 1: Subxiphoid view

Figure 2: RUQ view

Figure 3: LUQ view

Figure 4: Pelvic view (transverse).

Figure 5: Pelvic view (longitudinal).

Figure 6: Chest X-Ray

Discussion:

The extended Focused Assessment with Sonography for Trauma (eFAST) is a validated rapid, bedside trauma tool, classically validated in hemodynamically unstable patients with blunt trauma where delays in imaging may be fatal. However its use in penetrating trauma is situational. The sensitivity of ultrasound is significantly lower for bowel injury, retroperitoneal bleeding, and intra-abdominal bleeding [1]. This patient was hemodynamically stable, which typically decreases the urgency for bedside ultrasound. However the patient’s agitation, tachypnea, and uncertain injury trajectory of a subxiphoid entry wound made thoracic and abdominal evaluation critical.

The presence of pelvic free fluid (Figures 4,5) and tachycardia with hyperdynamic ventricles (Figure 1) raised concern for intra-abdominal injury and potential hemorrhage. The location of free fluid in a supine trauma patient is influenced by gravity, with the rectovesical or rectouterine pouch being common sites of accumulation [1]. This patient had been upright prior to arrival and was agitated and repositioned multiple times, raising the possibility that the visualized pelvic fluid was gravitational rather than an isolated pelvic organ injury.

Figure 7: Abdominal X-ray.

Free fluid was visualized only in the suprapubic view, which may be due to localized pelvic injury, supported by the bullet location on KUB (Figure 7), or redistributed by gravity from another source, given that the patient had been upright and repositioned prior to evaluation. The absence of fluid in the right or left upper quadrants does not exclude intra-abdominal hemorrhage, particularly in the setting of penetrating trauma, where eFAST sensitivity varies significantly by region and injury type [1,2].  Retroperitoneal bleeding or bowel injury are often missed with eFAST alone, both possibilities in this case.

A meta analysis of over 24,000 trauma patients demonstrated eFAST sensitivity and specificity, respectively, for intra-abdominal free fluid (74%, 98%), pericardial effusion (91%, 94%), pneumothorax (69%, 99%) [2]. In the suprapubic view, sensitivity ranges from 80 - 90%, with specificity ~ 99%, and detection thresholds as low as 100 - 150 mL [2]. The RUQ view, Morison’s pouch, has a sensitivity 85 - 96% and specificity 98%, but typically requires at least 200 mL of fluid for reliable detection [2]. The LUQ view, splenodiaphragmatic space, demonstrates sensitivity 70 - 85% with specificity 98 - 99% [2]. These ranges reflect variations in body habitus, fluid pooling, and operator dependency. These views are widely taught per guidance of the ACEP Sonoguide [5].

A randomized controlled trial found that while FAST did not reduce mortality, it significantly improved workflow and led to a faster time to diagnosis, fewer CT scans, shorter hospital stays, and lower costs [3]. Additional studies have shown that even when eFAST yields false negative results, outcomes are favorable as long as patient status is closely monitored and reassessed [4]. These statistics demonstrate eFAST’s strength in ruling in injuries when positive, but its limitations in ruling out injuries when negative, especially in penetrating trauma, where sensitivity can range from 28-100% depending on trajectory, organ involved, and injury severity [5]. 

In this case, eFAST was used as an adjunct to clinical decision making, not a replacement for formal imaging or serial exam. Its findings enabled structured handoff, avoiding unnecessary invasive interventions, and highlighted how point-of-care ultrasound can be safely integrated into trauma workflows even when patients fall outside classical indications. Additional data are needed to clarify how patient position prior to arrival, upright versus supine, affects the sensitivity and specificity of eFAST in trauma assessment, particularly in the evaluation of intra-abdominal free fluid. 

References:

  1. Tewari V, et al. The efficiency of focused assessment with sonography for trauma (FAST) vs. CT in penetrating torso trauma. J Emerg Trauma Shock. 2024;17(1):3–9.
  2. Netherton S, Milne WK, Proctor C, et al. Diagnostic accuracy of eFAST in trauma: a systematic review and meta-analysis. Can J Emerg Med. 2019;21(6):727–738.
  3. Stengel D, Bauwens K, Sehouli J, et al. Point-of-care ultrasonography for diagnosing thoracoabdominal injuries: a randomized controlled trial. JAMA. 2017;317(11):1110–1119.
  4. Sierzenski PR, et al. Clinical outcomes after false-negative FAST in hypotensive trauma patients. BMC Emerg Med. 2023;23:45.
  5. American College of Emergency Physicians (ACEP). Trauma Ultrasound (eFAST). Sonoguide. Available at: https://www.acep.org/sonoguide/basic/fast
  6. https://www.bcpocus.ca/organscans/efast/
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Case 51: Utility of the Spine Sign in Detecting Pleural Effusion on POCUS

John Hermez

A 74 year-old male with a past medical history of metastatic castration-resistant prostate cancer complicated by cauda equina necessitating laminectomy decompression, chronic RLE DVT on apixaban and chronic hypotension presented to the emergency department accompanied by his spouse for altered mental status. Per the patient’s wife, he experienced cognitive decline and increasing weakness for one week prior to presentation. Two days prior to his arrival in the ED, the patient became more confused and agitated with his wife reporting that he appeared to be hallucinating intermittently. While he typically ambulates without assistance and straight-catheterizes himself, he has been unable to care for himself independently.

Vitals: BP 91/53 | Pulse 85 | Temp 98.1 °F (36.7 °C) | Resp 12 | Wt 92.3 kg (203 lb 7.7 oz) | SpO2 98% | BMI 29.1 kg/m²

Physical Exam:

On exam, the patient is in no acute distress and is oriented only to his name. He has diffuse anasarca with 2+ right lower extremity edema and 1+ left lower extremity edema. He is not pale or cyanotic and has shallow respirations on room air with diminished lung sounds and a flat JVP.

Labs: WBC 25.7 and initial lactate 2.2. Hb 9.5 PLT 98, Urine cloudy and orange, growth pending

ECG: NSR at 82 bpm with occasional PVCs, no evidence of ST changes

CXR: Compared to prior, there are new heterogenous bibasilar lung opacities and atelectasis possibly representing pneumonia. No definite pleural effusion or pneumothorax. Stable cardiac silhouette.

To clarify cardiac function and better characterize pulmonary status, a bedside point of care echocardiography was performed.

Figure 1: Trace pericardial effusion seen on parasternal short axis view.

Figure 2: Sagittal right sview demonstrating the thoracic spine sign

Discussion:

Radiographic imaging of the thorax is routinely performed in the ED to aid in the diagnosis of a wide range of cardiopulmonary manifestations. While upright chest x-rays are the Gold Standard for detecting pneumonia in patients, the detection of pleural effusion may be less clearly visualized. Meta-analysis has shown that the screening sensitivity of ultrasound may be 94% as compared to 51% for chest x-ray, in spite of having similar specificity.1 In this case, we rapidly obtained a point-of-care echocardiogram and pulmonary ultrasound to guide medical decision making in a patient with advanced metastatic disease and anasarca with equivocal radiograph.

A parasternal short axis view was obtained (figure 1) and demonstrated a trace pericardial effusion estimated to be 3mm without evidence of gross systolic dysfunction. Although the right ventricle was poorly visualized during diastole, the small volume of effusion and history of chronic hypotension was reassuring against tamponade physiology. Acquisition of a right subcostal view (figure 2) demonstrated the thoracic spine sign which is a reliable indicator of pleural effusion or hemothorax.2

Figure 3: Subcostal view labelled to identify anechoic pleural effusion (image courtesy of Stanford Medicine 25)5

The spine sign is a sonographic description of the visualization of vertebral bodies above the level of the diaphragm, which indirectly indicates that a thoracic fluid collection is present. When there is no thoracic free fluid present, an abrupt loss of the vertebral bodies occurs at the diaphragm due to air in the lungs impeding transmission.2 Pleural effusions and traumatic hemothorax can both represent fluid collections, hence the utility of subcostal imaging in the eFAST exam to evaluate thoracic trauma. One study on closed chest trauma has shown the absence of the spine sign to have a negative predictive value of 97.8% in assessing pleural effusion.3 The focused use of ultrasonography in the emergency department is regarded of high value in the early detection and diagnosis of multiple pathologies. Algorithmic exams such as the RUSH protocol provide rapid feedback on the physiology of a critically ill patient which can guide management and are recommended both by the American College of Emergency Physicians and Critical Care Societies.4 The potential applications of ultrasonography in resource-limited, austere environments by prehospital personnel are also of particular interest given novel advancements in AI-technology and focused training protocols.

In spite of a technically challenging exam, this case was an excellent example of the utility of multimodal imaging to clarify cardiopulmonary status in the ED. The patient was treated with broad antibiotic therapy for suspected urosepsis and admitted to the hospital for multidisciplinary care. He later was scheduled for therapeutic thoracentesis and surgical evaluation for a scapular fluid collection. 

References:

  1. Yousefifard M, Baikpour M, Ghelichkhani P, Asady H, Shahsavari Nia K, Moghadas Jafari A, Hosseini M, Safari S. Screening Performance Characteristic of Ultrasonography and Radiography in Detection of Pleural Effusion; a Meta-Analysis. Emerg (Tehran). 2016 Winter;4(1):1-10. PMID: 26862542; PMCID: PMC4744606.
  2. Dickman, E., Terentiev, V., Likourezos, A., Derman, A. and Haines, L., 2015. Extension of the Thoracic Spine Sign: A New Sonographic Marker of Pleural Effusion. Journal of Ultrasound in Medicine, 34(9), pp.1555-1561.
  3. Vargas CA, Quintero J, Figueroa R, Castro A, Watts FA. Extension of the thoracic spine sign as a diagnostic marker for thoracic trauma. Eur J Trauma Emerg Surg. 2021 Jun;47(3):749-755. doi: 10.1007/s00068-020-01459-1. Epub 2020 Aug 17. PMID: 32803497.
  4. Seif D, Perera P, Mailhot T, Riley D, Mandavia D. Bedside ultrasound in resuscitation and the rapid ultrasound in shock protocol. Crit Care Res Pract. 2012;2012:503254. doi: 10.1155/2012/503254. Epub 2012 Oct 24. PMID: 23133747; PMCID: PMC3485910.
  5. “The Spine Sign.” Edited by Stanford Medicine 25 Bedside Medicine Symposium, Stanford Medicine 25, Stanford Medicine 25 Bedside Medicine Symposium, stanfordmedicine25.stanford.edu/blog/archive/2018/thespinesign1.html. Accessed 25 May 2025.
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Case 50: Ventral Hernia Pain

Bradley Phillips

A 47-year-old female with a medical history of right nephrectomy complicated by incisional “Swiss cheese” ventral hernias with recurrent incarceration and bowel strangulation presented to the ED with acute abdominal pain localized to the ventral hernia, nausea, and vomiting.

About three years earlier, the patient had undergone an exploratory laparotomy while admitted for peritonitis, which revealed an ischemic segment of small bowel and incarcerated omentum within a ventral hernia. She then underwent omentectomy, small bowel resection with primary anastomosis, and ventral hernia repair.

Following this surgery, the patient had recurrence of the hernia and frequent admissions for small bowel obstruction (SBO), all managed nonoperatively with nasogastric tube decompression and small bowel follow-through. She was discharged from the last such admission the day before presentation, and at that time was tolerating a liquid diet, passing flatus and having bowel movements. She believed that advancing her diet at home had triggered her symptoms, which included 6-7 episodes of non-bloody, non-bilious emesis following a solid meal.

Vitals: BP 128/83 mmHg | Pulse 103 | Temp 98.7 °F (37.1 °C) | Resp 16 | SpO2 93%

On physical examination, the patient was in acute distress and tachycardic. Abdominal exam revealed distension, tenderness in the periumbilical area, and guarding without rebound, as well as a large ventral hernia adjacent to a well-healed midline scar. The right side of the hernia was firmer than the left side but was mostly reducible.

A focused bedside ultrasound exam of the bowel was performed using the curvilinear transducer.

Figure 1. A dilated loop of small bowel, shown here in long axis, measures 3.78 cm in diameter. Bowel wall distension increases the visibility of the plicae circulares.

Figure 2: A loop of small bowel shown in long axis with bidirectional intraluminal content flow, also known as to-and-fro peristalsis.

Computed tomography of the abdomen showed dilated loops of small bowel measuring up to 3.9 cm with fecalization of the internal contents and a transition point at the anastomotic site at the hernia mouth, confirming SBO. There was no radiographic evidence of ischemia or perforation. General surgery was consulted. It was thought that the obstruction was likely due to adhesions or stenosis at the prior anastomosis and unrelated to the large ventral hernia.

The patient was admitted and treated conservatively with intravenous fluids and nasogastric tube decompression. Small bowel follow-through showed delayed passage of contrast and slow return of bowel function. She was discharged on a full liquid diet with planned follow-up with minimally invasive surgery for complex hernia repair.

Discussion

SBO is a significant cause of morbidity and hospital admissions. In the United States, the annual incidence of SBO is approximately 350,000 cases [1,2]. Prolonged obstruction can cause intestinal ischemia and necrosis of the bowel wall [3]. Combined with increased intraluminal pressure from the obstruction, this can lead to bowel perforation, peritonitis, and sepsis. The overall mortality rate for SBO is approximately 10%, but it can increase to 30% in cases complicated by bowel necrosis or perforation [1].

Adhesions are the most common cause of SBO, responsible for 65-74% of cases, and typically result from previous abdominal or pelvic surgeries. Other risk factors for SBO include hernias, neoplasms, Crohn disease, radiation enteritis, volvulus and foreign bodies [1,4].

Patients with SBO typically present with abdominal pain (often colicky and centrally located), nausea and vomiting, and constipation or obstipation. On physical examination, there may be abdominal distension. Early in the course of the obstruction, bowel sounds may be high-pitched and hyperactive. Advanced SBO can present with hypoactive or absent bowel sounds as well as severe abdominal tenderness with signs of peritoneal inflammation [1,5-6]. An elevated lactate supports clinical concern for bowel ischemia [7-8]. This patient’s lactate was normal at 1.1 mmol/L, although at the time of her episode of bowel strangulation and ischemia three years earlier, it was 2.5 mmol/L (elevated).

The differential diagnosis of SBO includes the myriad non-obstructive causes of nausea, vomiting, and abdominal pain; functional small bowel obstruction (adynamic ileus, pseudo-obstruction); and large bowel obstruction.

If SBO is suspected, the American College of Radiology recommends early imaging, particularly abdominal CT, to evaluate the severity of the obstruction, identify the etiology, and detect complications such as volvulus, strangulation, closed-loop obstruction, and ischemia [5]. However, point-of-care ultrasound (POCUS) has been shown to have a sensitivity of 83% to 92% and specificity of 93% to 96% in the evaluation of SBOs, and its use can save time and reduce radiation exposure [9,10].

When performing a POCUS exam for SBO, the curvilinear probe should be used for adult patients. The exam can be started at the patient-identified point of maximum tenderness, with the examiner applying graded compression to slowly and gently displace air out of the way of the probe. Segments of small bowel should be inspected in both long and short axis for dilation (diameter greater than 2.5 cm), absent or to-and-fro peristalsis, the presence of a transition point, free fluid, and bowel wall edema. Once an area of interest is identified, examiners can switch to the linear probe to increase image resolution [11].

The presence of a transition point is highly specific for SBO, as it is not seen in ileus. On ultrasound, a transition point will appear as an area of dilated bowel adjacent to an area of decompressed bowel. In the duodenum and jejunum, bowel wall distension can increase the visibility of the plicae circulares. An edematous bowel wall appears thickened on ultrasound with decreased echogenicity [11].

Management of small bowel obstruction (SBO) involves both nonoperative and operative strategies, depending on the patient's clinical presentation and response to initial treatment. Surgical intervention is indicated in cases of generalized peritonitis or signs of bowel ischemia (e.g., fever, leukocytosis, tachycardia, metabolic acidosis, or evidence of ischemia on imaging) or if the obstruction fails to resolve after 3 days of nonoperative management [2,12].

The risk of recurrence of adhesive small bowel obstruction is higher in patients who are managed nonoperatively compared to those who undergo surgical management, with recurrence rates ranging from 13% to 29% over long-term follow-up periods. The risk of recurrence also increases with the number of prior SBO episodes [13-15].

References

1. Rami Reddy SR, Cappell MS. A Systematic Review of the Clinical Presentation, Diagnosis, and Treatment of Small Bowel Obstruction. Curr Gastroenterol Rep. 2017 Jun;19(6):28. doi: 10.1007/s11894-017-0566-9.

2. van Veen T, Ramanathan P, Ramsey L, Dort J, Tabello D. Predictive factors for operative intervention and ideal length of non-operative trial in adhesive small bowel obstruction. Surg Endosc. 2023 Nov;37(11):8628-8635. doi: 10.1007/s00464-023-10282-9.

3. Scaglione M, Galluzzo M, Santucci D, Trinci M, Messina L, Laccetti E, Faiella E, Beomonte Zobel B. Small bowel obstruction and intestinal ischemia: emphasizing the role of MDCT in the management decision process. Abdom Radiol (NY). 2022 May;47(5):1541-1555. doi: 10.1007/s00261-020-02800-3.

4. Miller G, Boman J, Shrier I, Gordon PH. Etiology of small bowel obstruction. Am J Surg. 2000 Jul;180(1):33-6. doi: 10.1016/s0002-9610(00)00407-4.

5. Expert Panel on Gastrointestinal Imaging; Chang KJ, Marin D, Kim DH, Fowler KJ, Camacho MA, Cash BD, Garcia EM, Hatten BW, Kambadakone AR, Levy AD, Liu PS, Moreno C, Peterson CM, Pietryga JA, Siegel A, Weinstein S, Carucci LR. ACR Appropriateness Criteria® Suspected Small-Bowel Obstruction. J Am Coll Radiol. 2020 May;17(5S):S305-S314. doi: 10.1016/j.jacr.2020.01.025.

6. Jackson P, Vigiola Cruz M. Intestinal Obstruction: Evaluation and Management. Am Fam Physician. 2018 Sep 15;98(6):362-367.

7. Tanaka K, Hanyu N, Iida T, Watanabe A, Kawano S, Usuba T, Iino T, Mizuno R. Lactate levels in the detection of preoperative bowel strangulation. Am Surg. 2012 Jan;78(1):86-8.

8. Ambe PC, Kang K, Papadakis M, Zirngibl H. Can the Preoperative Serum Lactate Level Predict the Extent of Bowel Ischemia in Patients Presenting to the Emergency Department with Acute Mesenteric Ischemia? Biomed Res Int. 2017;2017:8038796. doi: 10.1155/2017/8038796.

9. Gottlieb M, Peksa GD, Pandurangadu AV, Nakitende D, Takhar S, Seethala RR. Utilization of ultrasound for the evaluation of small bowel obstruction: A systematic review and meta-analysis. Am J Emerg Med. 2018 Feb;36(2):234-242. doi: 10.1016/j.ajem.2017.07.085.

10. Shokoohi H, Mayes KD, Peksa GD, Loesche MA, Becker BA, Boniface KS, Lahham S, Jang TB, Secko M, Gottlieb M. Multi-center analysis of point-of-care ultrasound for small bowel obstruction: A systematic review and individual patient-level meta-analysis. Am J Emerg Med. 2023 Aug;70:144-150. doi: 10.1016/j.ajem.2023.05.039.

11. Damewood S, Finberg M, Lin-Martore M. Gastrointestinal and Biliary Point-of-Care Ultrasound. Emerg Med Clin North Am. 2024 Nov;42(4):773-790. doi: 10.1016/j.emc.2024.05.006.

12. Azagury D, Liu RC, Morgan A, Spain DA. Small bowel obstruction: A practical step-by-step evidence-based approach to evaluation, decision making, and management. J Trauma Acute Care Surg. 2015 Oct;79(4):661-8. doi: 10.1097/TA.0000000000000824.

13. Behman R, Nathens AB, Mason S, Byrne JP, Hong NL, Pechlivanoglou P, Karanicolas P. Association of Surgical Intervention for Adhesive Small-Bowel Obstruction With the Risk of Recurrence. JAMA Surg. 2019 May 1;154(5):413-420. doi: 10.1001/jamasurg.2018.5248.

14. Medvecz AJ, Dennis BM, Wang L, Lindsell CJ, Guillamondegui OD. Impact of Operative Management on Recurrence of Adhesive Small Bowel Obstruction: A Longitudinal Analysis of a Statewide Database. J Am Coll Surg. 2020 Apr;230(4):544-551.e1. doi: 10.1016/j.jamcollsurg.2019.12.006.

15. Fevang BT, Fevang J, Lie SA, Søreide O, Svanes K, Viste A. Long-term prognosis after operation for adhesive small bowel obstruction. Ann Surg. 2004 Aug;240(2):193-201. doi: 10.1097/01.sla.0000132988.50122.de.

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