You take handover of an 84 year old man with presumed right-sided renal colic awaiting a CT KUB. You are called, he has suddenly deteriorated. On review you find his pain has worsened and he is pale, sweaty and hypotensive.
Is this a vagal response to pain, a reaction to his analgesia or something else? You scan his aorta.
Describe and interpret these scans
Image 1 & 2: Transverse views of the abdominal aorta. The aorta is aneurysmal measuring about 10cm in diameter. There is intraluminal lamellated thrombus against the posterolateral and left aortic wall.
Acute predominantly hypoechoic retroperitoneal haemorrhage is seen anteriorly and to the right of the aorta – causing what was initially thought to be right-sided renal colic.
Ruptured abdominal aortic aneurysm with retroperitoneal haematoma
As an abdominal aortic aneurysm slowly expands it is common for layers of thrombus to form against the inner surface of the aneurysmal wall.
Whilst ultrasound can readily measure the size of the aorta and hence detect an aortic aneurysm, it cannot reliably exclude the presence of a leak or rupture. It can sometimes confirm rupture if retroperitoneal haematoma is detected. This tends to dissect retroperitoneally toward the left, often displacing the left kidney inferolaterally.
On this occasion blood tracked to the right mimicking right-sided renal colic. The blood seen here is hyperacute and has not yet clotted completely – much of it still appears hypoechoic and liquid – it appears to flow as the adjacent aorta pulsates.