(See also Overview of Abdominal Trauma Overview of Abdominal Trauma The abdomen can be injured in many types of trauma; injury may be confined to the abdomen or be accompanied by severe, multisystem trauma. The nature and severity of abdominal injuries vary... read more .)
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.
Grades of Hepatic Injury
Grade | Injury |
|---|---|
1 | Subcapsular hematoma < 10% of surface area Laceration < 1 cm deep |
2 | Subcapsular hematoma 10‒50% of surface area, intraparenchymal hematoma < 10 cm Laceration 1‒3 cm deep and < 10 cm long |
3 | Subcapsular hematoma > 50% of surface area, intraparenchymal hematoma > 10 cm or any expanding or ruptured hematoma Laceration > 3 cm deep |
4 | Parenchymal disruption involving 25‒75% of a hepatic lobe or 1‒3 Couinaud segments within a single lobe |
5 | Parenchymal disruption involving > 75% of a hepatic lobe or > 3 Couinaud segments Juxtahepatic venous injuries (ie, retrohepatic vena cava or central major hepatic veins) |
6 | Hepatic avulsion |
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 Shock Shock is a state of organ hypoperfusion with resultant cellular dysfunction and death. Mechanisms may involve decreased circulating volume, decreased cardiac output, and vasodilation, sometimes... read more . 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 Endoscopic retrograde cholangiopancreatography (ERCP) Imaging is essential for accurately diagnosing biliary tract disorders and is important for detecting focal liver lesions (eg, abscess, tumor). It is limited in detecting and diagnosing diffuse... read more 
(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
The manifestations of severe abdominal hemorrhage, including hemorrhagic shock, and abdominal pain, tenderness, and distention, are usually clinically obvious. Lesser hemorrhage or hematomas cause right upper quadrant abdominal pain and tenderness.
Diagnosis
Imaging (CT or ultrasonography)
A hepatic injury is confirmed with CT in stable patients and with bedside ultrasonography or exploratory laparotomy in unstable patients.
Treatment
Observation
Sometimes embolization or surgical repair
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 Shock Shock is a state of organ hypoperfusion with resultant cellular dysfunction and death. Mechanisms may involve decreased circulating volume, decreased cardiac output, and vasodilation, sometimes... read more , 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 Treatment reference Hepatic injury can result from blunt or penetrating trauma. Patients have abdominal pain, sometimes radiating to the shoulder, and tenderness. Diagnosis is made by CT or ultrasonography. Treatment... read more ). However, the more severe the injury, the more care should be taken before permitting resumption of activities that may involve heavy lifting, contact sports, or torso trauma.
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. Hepatectomy and even partial resection are rarely done
Treatment reference
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. doi: 10.1097/TA.0b013e318270160d
Key Points
The main immediate consequence of hepatic injuries 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.
Complications include formation of biliary fistulas, bilomas, and abscesses.
Confirm the diagnosis by CT in stable patients.
Treat patients using laparotomy (if unstable), observation (if stable), or sometimes selective angiographic embolization (eg, if stable but requiring ongoing transfusion).
