Hepatic Injury
(See also Overview of Abdominal Trauma.)
Etiology
Significant impact (eg, motor vehicle crash) can damage the liver, as can penetrating trauma (eg, knife wound, gunshot wound). Hepatic injuries range from subcapsular hematomas and small capsular lacerations to deep parenchymal lacerations, major crush injury, and vascular avulsion.
Classification
Hepatic injuries are classified according to severity into 6 grades (see table Grades of Hepatic Injury).
Grades of Hepatic Injury
Pathophysiology
The main immediate consequence is hemorrhage. The amount of hemorrhage may be small or large, depending on the nature and degree of injury. Many small lacerations, particularly in children, cease bleeding spontaneously. Larger injuries hemorrhage extensively, often causing hemorrhagic shock. Mortality is significant in high-grade liver injuries.
Complications
The overall incidence of complications is < 7% but can be as high as 15 to 20% in high-grade injuries. Deep parenchymal lacerations can lead to a biliary fistula or biloma formation. In biliary fistula, bile leaks freely into the abdominal or thoracic cavity. A biloma is a contained collection of bile similar to an abscess. Bilomas are typically treated with percutaneous drainage. For biliary fistulas, biliary decompression through endoscopic retrograde cholangiopancreatography (ERCP) is highly successful.
Abscesses develop in about 3 to 5% of injuries, often because of devitalized tissue being exposed to biliary contents. Diagnosis is suspected in patients in whom pain, temperature, and white blood count (WBC) increase in the days after injury; confirmation is by CT. Abscesses are usually treated with percutaneous drainage, but laparotomy may be necessary when percutaneous management fails.
Symptoms and Signs
Diagnosis
Treatment
Hemodynamically stable patients who have no other indications for laparotomy (eg, hollow viscus perforation) can be observed with monitoring of vital signs and serial hematocrit (Hct) levels. Patients with significant ongoing hemorrhage (ie, those with hypotension and shock, significant ongoing transfusion requirements, or declining Hct) require intervention. Patients whose vital signs are stable but who require ongoing transfusion may be candidates for angiography with selective embolization of bleeding vessels. Unstable patients should undergo laparotomy.
Success rates for nonoperative management are about 92% for grade 1 and 2 injuries, 80% for grade 3 injuries, 72% for grade 4 injuries, and 62% for grade 5 injuries. Following nonoperative management, there is no consensus in the literature regarding length of intensive care unit (ICU) stay, hospital stay, resumption of diet, duration of bedrest, or limitation of activity once discharged (1).
When surgery is done, small lacerations can typically be sutured or treated with hemostatic agents (eg, oxidized cellulose, fibrin glue, mixtures of thrombin and powdered gelatin). Surgical management of deeper and more complex injuries can be complicated.
Treatment reference
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Stassen NA, Bhullar I, Cheng JD: Nonoperative management of blunt hepatic injury: An Eastern Association for the Surgery of Trauma practice management guideline. J Trauma Acute Care Surg 73:S288-S293, 2012.
Key Points
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The main immediate consequence is bleeding, which often stops spontaneously, particularly if injuries are grade 1 or 2, but may require embolization or surgical repair; mortality and morbidity can be significant in high-grade injuries.
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Complications include formation of biliary fistulas, bilomas, and abscesses.
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Confirm the diagnosis by CT in stable patients.
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Treat patients using laparotomy (if unstable), observation (if stable), or sometimes selective angiographic embolization (eg, if stable but requiring ongoing transfusion).
