Retroperitoneal hemorrhage

Retroperitoneal haemorrhage can be a source of significant yet occult blood loss.

Clinical presentation

The clinical features are varied depending on the amount of hemorrhage present, rate of onset and ability of the surrounding structures to contain the hemostatic system. The classical features are:

• acute abdominal and/or flank pain
• hypotension
• anaemia

However, presentation is often non-specific with a lack of cutaneous bruising or other localising signs that can mean a delay in presentation and diagnosis.

Pathology

CausesAetiology

• pelvic, abdominal or lumbar trauma (e.g. pelvic fractures)
• blood dyscrasia
• rupture arterial aneurysm (e.g. abdominal aortic aneurysm)
• interventional or surgical procedures
• bleeding from underlying renal or adrenal pathology (e.g. renal AML; renal trauma)
• rarely spontaneous retroperitoneal haemorrhage (SRH) - anticoagulation/fibrinolytic therapy

Clinical features

The clinical features are varied depending on the amount of hemorrhage present, rate of onset and ability of the surrounding structures to contain the hemostatic system. The classical features are:

• acute abdominal and/or flank pain
• hypotension
• anaemia

However, presentation is often non-specific with a lack of cutaneous bruising or other localising signs that can mean a delay in presentation and diagnosis.

Radiographic features

The radiographic features can be variable depending on the stage of the haematoma.

Plain film - abdominal radiograph

NonAbdominal radiographi is typically non-specific but may show:

• obliteration of psoas muscle outline
• displaced bowel loops
• in case of an aortic aneurysm as the cause, there may be calcification of aortic aneurysm giving a clue towards the cause in the correct correct clinical context

Ultrasound

• spillage of haemorrhage into the peritoneal cavity can be picked up
• a large haematoma in the retroperitoneum may be seen
• may show indirect evidence of displacement of retroperitoneal structures
• the presence of an abdominal aortic aneurysm with peri-aortic haemorrhage could favour a ruptured aortic aneurysm as the cause

CT

• retroperitoneal structures have a hazy margin with fluid tracking through the retroperitoneum
• non contrast-contrast
  • acute and subacute haematomas - heterogeneous high attenuation
  • chronic haematomas - low attenuation
• contrast-enhanced CT - without(without dedicated angiography)
  • well-defined margin in case of a formed hematoma and absence of contrast enhancement

CT angiography

On angiography an active bleeding point or the breach in the wall of aneurysm (if its an underlying cause) may be identified.

MRI - MRA/MRA

On MRI a retroperitoneal haematoma has a variable appearance depending on the stage of the blood. It helps in better assessment as it can distinguish between blood and a neoplasm:

• acute and subacute stages -: hyperintense on T1- and T2-weighted images
• chronic stage -: hypointense is present on T1- and T2-weighted images

Treatment and prognosis

Management is based on the overall clinical context and vitals signs of the patient, the cause and stage of the haemorrhage.

Medical

Initial medical management involves:

• correction of coagulation disorders
• reversal of any anticlotting therapies (e.g. octaplex for warfarin)
• intravenous fluid resuscitation
• blood transfusion
• admission to an appropriate level of care (e.g. HDU for significant bleeds)

Although no consensus guidelines exist for retroperitoneal haemorrhage, it is accepted that patients with small haematomas or without ongoing bleeding can be managed conservatively.

Interventional radiology

It was previously thought that spontaneous retroperitoneal haemorrhage is related to microvascular causes which cannot be treated endovascularly. However, endovascular treatments now have a proven role in management, including:

• stent graft placement
• arterial embolisation

Chronic haematomas can become infected and are evacuated by percutenouspercutaneous drainage or surgery. It has a better prognosis compared to that of the acute type.

Surgery

Inappropriate surgical evacuation can exacerbate haemorrhage by relieving haematoma induced tamponade. However, active retroperitoneal hemorrhagehaemorrhage giving a large intra-abdominal haemoperitoneum can be fatal, and can require emergency surgery.

Differential diagnosis

• psoas haematoma -: often thought as a type of retroperitoneal haemorrhage but occurs posterior to the retroperitoneum in the iliopsoas compartment