What is a large volume hemoperitoneum?

Large Volume Hemoperitoneum: Definition and Clinical Significance

A large volume hemoperitoneum is defined as the presence of at least 500 ml of blood within the peritoneal cavity, which is the minimum amount typically detectable on emergency ultrasound imaging. 1

Definition and Detection

• Large volume hemoperitoneum refers to significant intraperitoneal blood accumulation (≥500 ml), which can be detected through various imaging modalities, particularly emergency ultrasound (EUS) 1
• The abundance of hemoperitoneum on Extended Focused Assessment with Sonography for Trauma (E-FAST) correlates with the need for laparotomy - 3 positive E-FAST sites indicates abundant hemoperitoneum and is associated with 61% appropriate laparotomies 2
• CT scan with intravenous contrast offers high sensitivity (93.9%) and specificity (77.8%) for detecting active bleeding compared to angiography 2

Causes

• Traumatic causes are common, including blunt or penetrating injuries to solid organs (liver, spleen) or abdominal vasculature 3
• Non-traumatic causes include:
  • Iatrogenic complications from surgery or interventional procedures 3
  • Complications of anticoagulation therapy 3
  • Blood dyscrasias such as hemophilia 3
  • Tumor-associated hemorrhage (hepatocellular carcinoma, hepatic adenoma, vascular metastases) 3
  • Gynecologic conditions (hemorrhagic ovarian cysts, ruptured ectopic pregnancy) 3
  • Vascular lesions (visceral artery aneurysms and pseudoaneurysms) 3
  • Spontaneous hemoperitoneum of unknown etiology (rare) 4, 5

Clinical Significance

• Large volume hemoperitoneum is a potentially life-threatening condition that can lead to hemorrhagic shock and requires prompt diagnosis and management 2
• The presence of large hemoperitoneum alone is considered a risk factor for non-operative management failure in splenic injuries, though it is not an absolute contraindication 1
• Hemodynamic stability is the key factor in determining management strategy for patients with hemoperitoneum 2

Diagnostic Considerations

• E-FAST is the initial imaging tool of choice for detecting hemoperitoneum in trauma settings, especially when CT scanning is not immediately possible due to hemodynamic instability 6
• Important pitfalls in diagnosing hemoperitoneum include:
  • Blood clots form rapidly in the peritoneum and have sonographic qualities similar to soft tissue, potentially being overlooked 1
  • Perinephric fat may be mistaken for hemoperitoneum 1
  • Fluid in the stomach or bowel may be mistaken for hemoperitoneum 1
  • Peritoneal free fluid is not identified by EUS until at least 500 ml is present, meaning a negative exam does not preclude early or slowly bleeding injuries 1
  • Non-traumatic fluid collections such as ascites may be mistakenly attributed to trauma 1

Management Approach

• For hemodynamically unstable patients with large volume hemoperitoneum, immediate resuscitation measures should include IV access, fluid resuscitation, and blood products if necessary 2
• E-FAST, chest X-ray, and pelvic X-ray should be performed to identify bleeding source in hemodynamically unstable patients 2
• For hemodynamically stable patients with large volume hemoperitoneum, thoraco-abdomino-pelvic CT scan with intravenous contrast should be performed for complete injury assessment 2
• Angiography/embolization may be considered for active arterial bleeding in hemodynamically stable patients 2
• Emergency laparotomy is indicated for abundant hemoperitoneum in unstable patients despite resuscitation efforts 2