Diagnosis

Colon Injuries
Most colonic injuries are identified at laparotomy performed for injury to other organs. Penetrating injury to the colon usually presents with peritonitis. This may develop over the course of a few hours and therefore serial physical examination is important for patients who are being managed non-operatively.

Colon & Rectum

Introduction
Diagnosis
Management - History
Management - Colon
Management - Rectum
Management - Guidelines
References

In patients where there is clinical suspicion of injury without overt signs, or clinical examination is impossible or unreliable (unconscious, intoxicated, spinal cord injury) then other modalities must be employed. The options are Computed Tomography (CT), Diagnostic Peritoneal Lavage (DPL) and Laparoscopy. Neither diagnostic peritoneal lavage nor laparoscopy will adequately evaluate the colon - especially the retroperitoneal colon.

Computed Tomography
CT is rapidly becoming the investigation of choice for evaluating blunt abdominal trauma in the haemodynamically normal patient. Colonic injury is suggested by free extraluminal air, intra-peritoneal or retro-pertioneal free fluid, focal thickening of the bowel wall, bowel wall haematoma or intra-mural air. Scans should be viewed on both abdominal and 'bone' windows to increase the sensitivity for free air. The overall accuracy of CT for evaluating bowel injury is 82%, with a sensitivity of 64% and a specificity of 97%. These figures may be improved with the use of triple-contrast (IV, oral and rectal) although the use of oral and rectal contrast is not universal. CT may also be useful in excluding peritoneal violation and allowing early discharge rather than admission for observation.

Rectal Injuries
A high index of suspicion for trauma is vital if injuries are not to be missed. In blunt trauma, rectal injuries are most commonly associated with pelvic fractures. Rectal examination should be performed on all pelvic injuries, looking for blood and bone fragments lacerating the rectal wall. If there is any doubt about the disagnosis, rigid sigmoidoscopy should be performed. When identified early and managed appropriately, open pelvic fractures have a mortality approaching that of closed injuries. However, in the presence of a missed rectal injury, the mortality may be as high as 50%.

Penetrating rectal injuries may be caused by injuries to the abdomen, thigh or buttock, as in the case presented. Again, any penetrating wound that may have injured the rectum should be fully evaluated with digital examination and proctoscopy/sigmoidoscopy. Even with these examinations it is possible to miss a significant rectal injury.

Management - History