What is a hepatic laceration?

What is a Hepatic Laceration

A hepatic laceration is a traumatic tear or cut through the liver parenchyma (liver tissue), typically resulting from blunt or penetrating abdominal trauma, that disrupts the liver's structural integrity and can cause hemorrhage, bile leakage, and associated complications. 1

Anatomic Definition and Pathophysiology

• A hepatic laceration represents a disruption of the liver capsule and underlying parenchyma, creating a tear that extends into the liver substance with varying depth and complexity 1
• The injury involves damage to hepatic blood vessels (hepatic artery branches, portal vein tributaries, and hepatic veins) and bile ducts within the liver tissue, leading to the two primary complications: hemorrhage and bile leak 1
• Lacerations can occur anywhere in the liver but may be limited to specific anatomic regions, including the "bare area" (the posterior surface not covered by peritoneal reflection), which can present without intraperitoneal bleeding 2

Severity Classification

The severity of hepatic lacerations is graded using the American Association for the Surgery of Trauma (AAST) system, which ranges from Grade I (minor) to Grade VI (fatal):

• Grade I: Subcapsular hematoma <10% surface area or capsular tear <1 cm parenchymal depth 3, 4
• Grade II: Subcapsular hematoma 10-50% surface area, intraparenchymal hematoma <10 cm, or laceration 1-3 cm depth and <10 cm length 3, 4
• Grade III: Subcapsular hematoma >50% surface area or expanding/ruptured hematoma, intraparenchymal hematoma >10 cm, or laceration >3 cm depth 3, 4
• Grade IV-V: More extensive injuries involving major vascular structures or massive parenchymal destruction 1

Clinical Significance and Complications

The primary life-threatening consequence of hepatic laceration is exsanguination, which represents the leading cause of death in liver injuries. 1

Immediate Complications:

• Hemorrhage: Active arterial or venous bleeding that can lead to hemodynamic instability and death within minutes if uncontrolled 1, 5
• Hemodynamic shock: Defined as blood pressure <90 mmHg with heart rate >120 bpm, altered consciousness, or evidence of vasoconstriction 5

Delayed Complications (occurring in 12-14% of patients after high-grade injury):

• Re-bleeding or secondary hemorrhage: Occurs in 1.7-5.9% of cases with mortality up to 18%, often from subcapsular hematoma rupture or pseudoaneurysm 1
• Biliary complications: Including biloma (bile collection), biliary fistula, hemobilia (bleeding into bile ducts), and bile peritonitis, with incidence of 2.8-30% 1
• Hepatic artery pseudoaneurysm: Rare (1% prevalence) but high-risk complication requiring urgent treatment to prevent rupture 1
• Abscesses: Occur in 0.6-7% of severe lesions, typically requiring percutaneous drainage 1
• Hepatic necrosis: Can occur after arterial ligation or extensive devascularization 1

Diagnostic Approach

• Contrast-enhanced CT scan is the gold standard for defining anatomic injury extent, identifying active bleeding (arterial blush), and detecting associated injuries in hemodynamically stable patients 3, 4
• Ultrasound is useful for assessing bile leak/biloma in grade IV-V injuries, especially with central lacerations 1
• Diagnostic peritoneal lavage may miss lacerations limited to the bare area of the liver, as these injuries may not produce intraperitoneal bleeding 2

Management Principles

Management decisions are determined primarily by hemodynamic status, NOT by the anatomic grade of the laceration alone. 3, 5, 4

• Hemodynamically stable patients: Non-operative management (NOM) is the standard of care regardless of laceration grade, with intensive monitoring, serial examinations, and CT imaging 3, 4
• Hemodynamically unstable patients: Require immediate operative management with damage control surgery, regardless of laceration grade 1, 5
• Active arterial bleeding on CT in stable patients: Proceed directly to angioembolization as primary intervention 5, 6

Critical Clinical Pitfall

Never assume all hepatic lacerations can be managed non-operatively based solely on anatomic grade—hemodynamic status trumps anatomic classification and fundamentally changes management from observation to immediate surgery. 3, 5