Liver Laceration

Epidemiology & Etiology

The liver is the most common solid organ injured in blunt abdominal trauma, typically secondary to motor vehicle collisions, falls, or direct blows. Penetrating trauma (stab/gunshot wounds) is less common but highly lethal due to immediate exsanguination. The right lobe is disproportionately affected due to its larger size and proximity to the ribs.

Pertinent Anatomy

Situated in the right upper quadrant, the liver is partially protected by ribs 7-11, meaning lower right rib fractures highly correlate with hepatic injury. It is highly vascularized by the portal vein (75% of blood supply) and hepatic artery, making massive intraperitoneal hemorrhage the primary threat upon capsular breach.

Pathophysiology

Direct impact or deceleration forces cause shearing of the hepatic parenchyma and Glisson's capsule. This mechanical disruption leads to extravasation of blood and bile into the peritoneal cavity. Uncontrolled bleeding rapidly progresses to hypovolemic shock, while pooled blood and bile cause intense peritoneal irritation. Severe crushing forces can cause complete hepatic avulsion or injury to the retrohepatic vena cava, which carries a massive mortality rate.

Clinical Manifestations

Patients typically present with localized RUQ pain, tenderness, and abdominal wall guarding. Blood irritating the right hemidiaphragm produces a classic right-sided Kehr sign (referred shoulder pain). Carefully evaluate for signs of hemorrhagic shock, including tachycardia, hypotension, narrowed pulse pressure, and altered mental status. Concomitant lower right rib fractures or abdominal wall ecchymosis strongly suggest underlying hepatic trauma.

Diagnosis

The FAST exam is the initial triage tool to detect hemoperitoneum in hemodynamically unstable trauma patients. For hemodynamically stable patients, CT abdomen/pelvis with IV contrast is the gold standard diagnostic test. CT defines the AAST injury grade (I-VI) and identifies active arterial extravasation, seen as a contrast blush. Serial hemoglobin and hematocrit monitoring is essential to track ongoing occult blood loss.

Treatment

Non-operative management (NOM) is the first-line approach for hemodynamically stable patients lacking peritonitis, involving ICU admission, bed rest, and serial abdominal exams. Angiography with transcatheter embolization is indicated for stable patients showing a contrast blush on CT. Exploratory laparotomy is the mandatory emergency intervention for patients with hemodynamic instability and a positive FAST, or those with overt peritonitis. Surgical techniques include the Pringle maneuver (clamping the hepatoduodenal ligament) to control inflow hemorrhage.

Prognosis

Most low-grade (I-III) lacerations heal without surgical intervention. Severe injuries risk delayed hemorrhage, typically occurring within the first 72 hours. Biliary complications, such as bilomas or biliary fistulas, may require ERCP and stenting. A rare but classic complication is hemobilia, presenting weeks later with Quincke's triad (RUQ pain, jaundice, and upper GI bleeding).

Differential Diagnosis