Renal and hepatic lacerations in a trauma patient

Case Discussion

In this case, there is fluid surrounding the right kidney, lying dependently in Gerota's fascia. This is associated with right sided postero-inferior renal laceration sparing the renal pelvis.
There is also fluid lying anterior the liver, with the laceration appearing in hepatic segments five and six.

Traumatic renal injury is a relatively uncommon occurrence, which is found in 1-5% of all traumas ¹. They are typically caused by blunt injury mechanisms, in particular, motor vehicle accidents and falls from height.

Traumatic renal injury can be graded from 1 though to 5. The grading system is defined as follows ²:

• grade I - contusion or non-expanding subcapsular hematoma; no laceration
• grade II - non-expanding perirenal hematoma; cortical laceration <1cm deep without extravasation
• grade III - cortical laceration > 1 cm without urinary extravasation
• grade IV - laceration through corticomedullary junction into collecting system OR vascular segmental renal artery or vein injury with contained hematoma
• grade V - shattered kidney OR renal pedicle injury or avulsion

Stable patients with grade 1 to 4 lacerations tend to be managed conservatively. Grade 5 injuries, or unstable patients with lesser grade injuries require intervention. Unstable patients may have life-threatening hemorrhage, renal pedicle avulsion or expanding retroperitoneal hematomas.

Management options are either with open surgical exploration or interventional angioembolisation. Nephrectomy is usually preferred over repair for severe lacerations, unless there is a contra-indicating factor such as a solitary kidney or bilateral kidney injury.

Liver injury is a common finding in many types of trauma ³. This is because of its anterior location, as well as fragile parenchyma.

Investigations into traumatic liver injury involves focussed assessment for trauma using ultrasound (FAST scans), CT or with diagnostic peritoneal lavage. Imaging such as radiography may reveal chest fractures or splenic lacerations, both common associated injuries.

Traumatic liver injury can be divided into six categories according to the American Association for the Surgery of Trauma ⁵. This particular patient had a grade III hepatic laceration.

• grade I – hematoma: subcapsular <10 percent surface area; laceration: capsular tear <1 cm parenchymal depth
• grade II – hematoma: subcapsular 10 to 50 percent surface area or intraparenchymal <10 cm in diameter; laceration: capsular tear 1 to 3 cm parenchymal depth, <10 cm in length
• grade III – hematoma: subcapsular >50 percent of surface area or ruptured subcapsular or parenchymal hematoma; intraparenchymal hematoma >10 cm or expanding; laceration >3 cm in depth
• grade IV – laceration: parenchymal disruption involving 25 to 75 percent of a hepatic lobe, or 1 to 3 Couinaud segments
• grade V – laceration: parenchymal disruption of >75 percent of a hepatic lobe, >3 Couinaud segments within a single lobe; vascular: juxtahepatic venous injuries (retrohepatic vena cava, central major hepatic veins)
• grade VI – hepatic avulsion

Patients with liver injury can be managed based on their degree of hemodynamic stability ⁴. This is regardless of the grading of the injury. Stable patients are usually managed conservatively with supportive care. One exception is if there is extravasation of IV contrast - these lesions are usually embolized via hepatic embolization.

An haemodynamically compromised patient with a liver laceration is an indication for operative management. This can involve both damage-control surgery, and liver resection in the severely compromised patient.

Case contributed by A/Prof. Pramit Phal.