22yo male was accidentally shot with a pellet gun while hunting with his brother! There were multiple external pellet wounds to his face anterior chest and abdomen. He was haemodynamically stable with 100% sats. Abdomen was soft and NT. ECG was SR with no irregularities. A plain CT chest and abdomen was ordered. EFAST was not done due to clinical stability and as he was due to have CT imaging.
Reviewing the CT chest: Matt and Lisa had a freak out moment when one of the pellets was located perilously close to the heart. A frantic call to the radiologist was slightly reassuring: the pellet seemed to be in the epicardial fat. However a contrast CT was organised to make sure.
coronal CT image of the chest showing an opaque pellet inferior to the heart.
However, ED cardiac US revealed something very different!
The initial parasternal long axis view was reassuring. There was a tiny pericardial effusion and a normal RV and LV.
If anything, the radiology report appears to be correct. A bit of angling reveals a reverberation articfact seemingly anterior to the RV.
Parasternal long axis view showing a reverberation artefact anterior to the RV (see below).
Parasternal long axis view showing the commet artefact anterior to the RV (red arrow). This is produced by small highly reflective structures such as metal or air. This was assumed to be the pellet.
However, the subcostal view was slightly more scary
Subcostal view of the heart clearly showing the origin of the reverberation artefact within the RV myocardium. Below is a still of the cine loop with the artefact highlighted in blue.
Subcostal short axis view showing this more clearly.
Zoomed in view of the RV in short axis.
Contrast CT revealed that the pellet was in the RV myocardium. However as there was minimal pericardial effusion and as the patient was stable this was treated conservatively. Repeat formal TTE revealed no change in the position of the pellet.
78yo female pedestrian versus car.
She was hit to the legs at >60kph and then thrown several meters. She was intubated at the scene due to decreasing GCS and transported to ED via HEMS.
She had no evidence of chest injuries. She had an epigastric bruise extending across the abdome, L elbow and thumb bruising and R open distal tib fib fractures. EFAST was negative. No other injuries were noted. She had normal LL pulses.
She was stable during transport except for a drop in SBP to 60 just prior to landing. A unit of pack cells was started by HEMS.
In the ED, she initially stabilised after the unit of pack cells, but then continued to have episodes of hypotension. ED cardiac ultrasound revealed a hyperdynamic LV, small collapsing IVC. Further pack cells were given but the source of bleeding was still indeterminate. Frustratingly, repeat EFAST was still negative!!
I didn't think to look at the aorta!
CTs revealed no injuries in the chest, no organ injury in the abdomen. However, the spleen was variegated with a prominent splenic artery ?splenic artery dissection with associated infarction. The abdominal aorta was not dilated but it was surrounded 180 degrees with ?haematoma: suggesting ? traumatic aortic dissection.
The patient was brought back to ED. She had ongoing episodes of hypotension which responded to fluid resuscitation.
These are her US images done upon return to ED.
Trans aorta (mid) showing a normal sized aorta anterior to the vertebra with surrounding haematoma (see below).
colour doppler images showing blood flowing into haematoma (see below).
CT image of dissection
Isolated abdominal aortic dissection is rare (1). There are only a handful of case reports of abdominal aortic dissection as a sequelae of blunt abdominal trauma (2,3). It has been described post MVA (3) and even Heimlich manoeuver (4) in elderly and young patients. It is most often picked up by CT. US diagnosis in the ED in the setting of trauma has not been described.
Some EFAST courses recommend starting the EFAST with a view of the aorta. Maybe in the patient with unexplained hypotension post abdominal trauma ultrasound images of the abdominal aorta should be considered.
1. Trimarchi S, Tsai T, Eagle KA, et al. International Registry of Acute Aortic Dissection (IRAD) investigators. Acute abdominal aortic dissection: insight from the International Registry of Acute Aortic Dissection (IRAD). J Vasc Surg 2007;46:913–19.
2. Berthet JP, Marty-Ané CH, Vecrapen R, Picard E, Mary H, Alric (2003) Dissection of the abdominal aorta in blunt trauma: endovascular or conventional surgical management? J Vasc Surg 38:997–1004
3. Martí M, Pinilla I, Baudraxler F, Simón MJ, Garzón G. A case of acute abdominal aortic dissection caused by blunt trauma. Emerg Radiol (2006) 12: 182–185.
4. Desai SC, Chute DJ, Desai BC, Koloski ER. Traumatic dissection and rupture of the abdominal aorta as a complication of the Heimlich maneuver. J Vasc Surg. 2008 Nov;48(5):1325-7