Bowel and mesenteric trauma injury grading

A number of bowel and mesenteric injury grading systems have been proposed and validated for trauma to the bowel and/or mesentery based on CT and clinical parameters.

Classifications

RAPTOR ¹

The RAdiographic Predictors of Therapeutic intervention score predicts the need for early therapeutic operative intervention by allocating points for the presence of 7 CT findings. Each finding is allocated 1 point when present and the score is the total, with a maximum score of 7.

CT findings:

• multifocal hematoma

• extravasation

• bowel hematoma

• devascularization

• fecalization

• pneumoperitoneum

• fat pad injury (abdominal wall seat belt sign)

A score of 3 or more suggests significant bowel and/or mesenteric injury and has specificity of 85% (score of 3), 87% (score of 4) and 95% (score of 5).

In the study ¹, the following definitions were used:

• therapeutic laparotomy: surgical findings included a bleeding mesenteric injury, full thickness bowel injury, or significant bowel deserosalisation requiring resection

• non-therapeutic laparotomy: surgical findings included a non-bleeding mesenteric injury, a serosal injury not requiring resection, or a solid organ injury

BIPS ²

The Bowel Injury Predicition score in blunt abdominal trauma is based on a combination of clinical findings and CT grade of mesenteric injury. Each parameter is allocated 1 point when present and the score is the total, with a maximum score of 3.

Parameters:

• white cell count of ≥17 g/l

• abdominal tenderness

• CT grade 4 or 5

CT grading of injury:

• grade 1: isolated mesenteric contusion (ill-defined ground glass haziness or wispy or streaky opacities within the mesenteric fat) without associated bowel wall thickening or adjacent interloop fluid collection

• grade 2: mesenteric hematoma (discrete, measurable, soft tissue density within the mesentery) < 5 cm without associated bowel wall thickening or adjacent interloop fluid collection

• grade 3: mesenteric hematoma > 5 cm without associated bowel wall thickening or adjacent interloop fluid collection

• grade 4: mesenteric contusion or hematoma (any size) with associated bowel wall thickening (thickening of the wall of small bowel > 3 mm) or adjacent interloop fluid collection (small triangular collection of free fluid within the mesentery and/or between the bowel loops)

• grade 5: active vascular or oral contrast extravasation bowel transection or pneumoperitoneum

A score of 2 or more is strongly associated with blunt hollow viscus injury .