An elderly lady was brought to the Emergency Dept by ambulance as a priority 1 with a presumptive diagnosis of "ruptured AAA" after collapse and abdominal pain. She was pale and hypotensive on the arrival of the ambulance crew. Examination revealed hypotension, pallor and a tender abdomen with a midline laparotomy scar. She was not on any anti-coagulants.
There was free fluid in the hepatorenal space (note that this was only seen in the anterior space with the probe pointed 'up' and it was possible to make the space look normal by viewing only the posterior space).
A large retroperitoneal haematoma was seen. The aorta was normal (not shown). There was a hypoechoic mass in the haematoma which did not show any flow.
She underwent urgent CT (with contrast) to determine the cause of the retroperitoneal bleeding which revealed multiple SMA and IMA aneurysms. These were treated with coiling and the bleeding stopped.
This case illustrates:
1) Most importantly - the spaces where we look for free fluid are 3 dimensional and so should be scanned through before concluding there is no fluid
2) The aorta is not the only source of retroperitoneal haemorrhage. Splenic artery aneurysms are the most common, but aneurysms can occur from other vessels. The presentation is similar to ruptured AAA.