An Elderly lady presented with collapse then complained of abdominal pain. A pulsatile mass was palpated in her abdomen.
An abdominal aortic aneurysm is shown in trans and long views. In addition, there was a 10 x 6 cm hetrogenous mass, consistent with haematoma seen to the side of the aorta, suggestive of a retroperitoneal haemorrhage. No free fluid was seen in the right or left upper quadrants or in the pelvis (images not shown)
Occasionally ultrasound may detect direct signs of rupture - either free fluid (with intra-abdominal rupture) or a retroperitoneal haematoma (such as in this case). Free fluid from a ruptured AAA is usually a preterminal sign, as there will be little tamponade effect to contain the intra-abdominal bleeding.
It is important to note that the absence of these signs of rupture does NOT exclude rupture. Ultrasound is relatively insensitive for excluding rupture (despite having good sensitivity to exclude an aortic aneurysm). It's role in these patients is generally to confirm or exclude the presence of an aneurysm. If the patient's condition allows, then further imaging with CT is usually performed to exclude or confirm rupture.
In this case, although the patient's condition had improved post collapse, she was transferred directly to theatre on the basis of the ultrasound.