Stassen et al used a diagnostic algorithm to evaluate patients with an abdominal seat belt sign. This can help reduce the missing of occult intestinal injuries yet minimize negative exploratory abdominal laparotomies. The authors are from the University of Louisville, Stanford University, and Memorial Regional Hospital in Hollywood, Florida.



(1) The abdominal seat belt sign may be associated with occult injuries to the bowel and mesentery.

(2) The negative FAST protocol cannot exclude intestinal injury in these patients, so an abdominal-pelvic CT scan should be performed.

(3) A patient with a negative abdominal CT scan should be observed for at least 23 hours rather than discharged.

(4) Multiple repetitive CT scans may be needed to detect occult injuries.


Bowel injuries that may be found with the abdominal seat belt sign:

(1) small bowel perforation

(2) colon perforation

(3) mesenteric injury

(4) bowel deserosalization


The amount of intraperitoneal fluid is graded by the number of transverse cuts (taken at 10 mm) containing fluid (Brasel et al).

CT Cuts with Fluid

Grade of Fluid



1 to 3


4 or 5


>= 6



Observe for 23+ hours if the abdominal-pelvic CT is negative.


Manage conservatively:

(1) solid organ injury

(2) trace fluid without solid organ injury


Evaluate further, often with open laparoscopy:

(1) moderate to large amounts of free fluid without solid organ injury

(2) free air

(3) extravasation of oral contrast

(4) mesenteric stranding

(5) bowel wall thickening



• I am a little unsure about the optimum handling of a patient with a large amount of free fluid with a solid organ injury.


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