The other EPSS

Written by: Dr. Seldon (Edwin) Davis

Edited by: Dr. Joann Hsu

The case:

35 YO M with pmh Crohn’s disease brought in by EMS for hematemasis, found to be pale and diaphoretic on scene, passed out, and became unresponsive. Patient was brought to the ED intubated.

Exam was limited since he was unresponsive and intubated but abdominal distension was noted.

Bedside abdominal ultrasound in the RUQ showed:

RUQ with free fluid noted

Notice what looks like A lines coming in and out of the screen from the left, over the liver.

Again, the A lines over the liver.

Further imaging showed:

  • CT Abdomen/pelvis with IV contrast

    • Pneumoperitoneum with diffuse large and small bowel wall thickening,

      most pronounced in the pelvic small bowel which is perforated

    • Moderate to large volume complex ascites, peritonitis, and multiple

      loculated mesenteric gas and fluid-filled collections.

EPSS Basics

  1. EPSS: Enhanced Peritoneal Stripe Sign

    1. Enhanced (bright) echogenic line at the peritoneum

  2. Concerning for pneumoperitoneum (free air within the abdomen)

    1. EPSS is produced as the air interrupts echogenic return of the ultrasound waves.

    2. The air causes a scattering of the ultrasound waves between the gas and soft tissue, producing a high-amplitude linear echo which leads to hyperechoic enhancement of the normal peritoneal stripe sign

    3. So what is highlighted is the interface between gas and soft tissue!

EPSS and other Ultrasonographic Findings concerning for Pneumoperitoneum

  1. EPSS

  2. Reverberation Artifact (A-lines in the Abdomen)

  3. Comet-Tail Reverberatory Artifacts

  4. Air Bubbles in Ascitic Fluid

EPSS is a classic finding concerning for pneumoperitoneum, however in the setting of substantial pneumoperitoneum, A-Lines can be visualized within the abdomen

***** Not to be confused with EPSS/E-Point Septal Separation, measurement of the of anterior Mitral Valve leaflet movement used as an estimate  for Left Ventricular Ejection Fraction

Tips and Tricks

  • Use a Linear/Curvilinear Transducer

  • Look for signs of air being intra-luminal within the bowel (peristalsis, dirty shadowing)

  • Look in the RUQ

    • Anterior aspect of liver is adjacent to the anterior abdominal wall

    • Not occupied by bowel, and should be free from bowel gas

  • Scissor Maneuver

    • Slight Pressure to ant. Abd --> free intraperitoneal air expelled from region anterior to liver to other parts of peritoneal cavity --> reverberation artifact becomes less prominent 

    • Then when pressure on distal end of probe is released, maintain contact with probe and skin surface --> free gas returns to the area and the A-lines become more prominent

    • In real time the repeated maneuver appears like opening and closing of scissors 

Literature

  • Perforated Viscus associated w/ pneumoperitoneum, is a life-threatening etiology of acute abdominal pain in the ER

    • Literature supports POCUS as a useful adjunct and tool to rapidly diagnose and expedite management

Back to the case:

  • The patient was taken to the OR and after an extensive hospital course, he was discharged to rehab for further recovery.

Happy scanning!

References

  1. Bacci M, Kushwaha R, Cabrera G, et al. (June 08, 2020) Point-of-Care Ultrasound Diagnosis of Pneumoperitoneum in the Emergency Department. Cureus 12(6): e8503. doi:10.7759/cureus.8503

  2. Carroll D, Elfeky M, Shah V, Peritoneal stripe sign (pneumoperitoneum). Reference article, Radiopaedia.org (Accessed on 29 Sep 2024) https://doi.org/10.53347/rID-65535

  3. Chao, A., Gharahbaghian, L., & Phillips, P. (2014, December 23). Diagnosis of Pneumoperitoneum with Bedsite Ultrasound. Western Journal of Emergency Medicine, 16(2).

  4. Indiran, V., Vinoth Kumar, R. & Jefferson, B. Enhanced peritoneal stripe sign. Abdom Radiol 43, 3518–3519 (2018). https://doi.org/10.1007/s00261-018-1628-7

  5. Kricun, B. J., & Horrow, M. M. (2012, June). Pneumoperitoneum. Ultrasound Quarterly, 28(2)

  6. Muradali D, Wilson S, Burns PN, Shapiro H, Hope-Simpson D. A specific sign of pneumoperitoneum on sonography: enhancement of the peritoneal stripe. AJR Am J Roentgenol. 1999 Nov;173(5):1257-62. doi: 10.2214/ajr.173.5.10541100. PMID: 10541100.

Booth EM