You are in: eMedicine Specialties > Radiology > GASTROINTESTINAL Bowel, TraumaArticle Last Updated: Sep 2, 2005AUTHOR AND EDITOR INFORMATIONAuthor: Raul N Uppot, MD, Instructor in Radiology, Harvard Medical School;, Assistant Radiologist, Department of Radiology, Section of Abdominal Imaging and Interventional Radiology, Massachusetts General Hospital Raul N Uppot is a member of the following medical societies: Radiological Society of North America Coauthor(s): John S Wills, MD, Associate Professor of Radiology, Thomas Jefferson University; Chair, Department of Radiology, Pennsylvania Hospital; Vinay K Gheyi, MD, MBBS, Chief of Radiology, Department of Radiology, McGuire VA Medical Center, Richmond, Virginia Editors: Neela Lamki, MD, Professor, Department of Radiology, Sultan Qaboos University, Oman; Adjunct Professor, Department of Radiology, Baylor College of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Spencer B Gay, MD, Professor of Radiology, Director of Body Computed Tomography, Department of Radiology, University of Virginia Health Sciences Center; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center Author and Editor Disclosure Synonyms and related keywords: abdominal injuries, intestinal injury, wounds nonpenetrating, wounds penetrating INTRODUCTIONBackgroundThe diagnosis and management of bowel trauma has evolved over many centuries. Historic methods One of the earliest descriptions of bowel trauma came from the Byzantine Empire (324-1453 CE). The historical writer Philostorgius (fifth century) described the fatal wounding of Emperor Julian the Apostate (361-363 CE) when he wrote, "a cavalryman severely wounded the emperor in the abdomen with his spear and injured the peritoneum and intestines; when the point of the weapon was pulled out, there followed an outflow of feces mixed with blood." For centuries, bowel trauma was managed conservatively, with occasional reports of the reduction of prolapsed portions of the GI tract. This treatment had a high mortality rate, and survivors escaped death by withstanding hemorrhage and sepsis. With the introduction of firearms at the Battle of Crecy in 1346, penetrating abdominal wounds became more severe. The first exploratory laparotomy was performed in 1834 by a French surgeon named ML Baudens. Baudens also recommended introducing a finger or small sponge through the abdominal wound to determine the presence of blood, feces, or bubbles of gas and, if present, to proceed with a laparotomy. This was the first diagnostic evaluation for bowel injury. In the early 1900s, Nicholas Senn, a surgeon, proposed to diagnose intestinal perforation using a technique termed the Senn hydrogen gas insufflation test. This diagnostic test involved insufflating hydrogen gas into the anus of a wounded patient. A lighted taper was then placed near the entrance wound. If a small explosion accompanied by a flaring blue flame occurred, this was considered a positive finding for intestinal perforation. A turning point in the conservative management of penetrating bowel trauma came after the assassination of President James Garfield in 1881. Although he was managed conservatively and died 3 months later of a mycotic aneurysm, his death brought the debate of abdominal exploration to academic discussion. During WWII, soldiers presenting with penetrating wounds underwent radiographic examinations, had nasogastric tubes inserted, received penicillin, and underwent exploratory laparotomy. From WWII to the Vietnam War, mortality from penetrating gunshot wounds decreased from 42-9%. With the introduction of radiography in the evaluation of blunt abdominal trauma, diagnostic accuracy improved. Abdominal radiographs could detect as little as 1 cm3 of free gas outside the intestinal tract. However, plain radiographs were nonspecific. Addition of conventional contrast procedures helped by identifying extravasation from perforated viscera. Modern methods In 1965, diagnostic peritoneal lavage (DPL) was introduced. DPL involves making a small midline incision and instilling 1 L normal saline or Ringer lactate into the peritoneum. Eluted fluid is examined for blood, particulate matter (fecal, vegetable), or bacteria. In 1971, the use of ultrasound (US) to evaluate blunt abdominal trauma was first reported. During this period, angiography also was used to evaluate blunt abdominal trauma to detect mesenteric, retroperitoneal, or solid organ hemorrhage. CT was invented in 1971. The use of CT to evaluate blunt abdominal trauma was first reported in 1979, when an EMI scanner was used to study blunt trauma in 4 patients. The identified injuries included lacerated spleen, hepatic hematoma, and 2 renal hematomas. Since 1979, the resolution and scanning time of CT have improved as well as its ability to detect bowel injury. Currently, multi-row helical detector CTs are capable of scanning the abdomen in less than 30 seconds and can detect free air, free fluid, abnormal bowel wall enhancement, bowel wall thickening, and mesenteric infiltration. These advances in CT have brought the debate of conservative management of abdominal trauma full circle. Currently, many patients with blunt abdominal trauma or retroperitoneal penetrating trauma can be managed without surgery and can avoid unnecessary laparotomy. Advances in the diagnosis and management of bowel abdominal trauma undoubtedly will proceed from advances in technology. Multidetector CT scanning using 16- and 64-slice CT has increased the speed in which trauma patients are scanned. In addition, 16- and 64-slice multidetector CT imaging allows the creation of isotropic voxels that allow reformats to be performed in sagittal and coronal planes, which can allow better localization of bowel injuries. Currently, CT is used in 3-dimensional reconstructions of the colon (CT colonography). The use of CT to reconstruct the entire alimentary tract to detect bowel trauma is not unreasonable. Interventional radiology and techniques of minimally invasive surgery also are revolutionizing treatment of bowel trauma. Laparoscopy is being used in hemodynamically stable patients with blunt abdominal trauma to identify and repair small bowel injuries. Percutaneous management of abscesses and hematomas provides a minimally invasive, although sometimes only temporary, alternative to open exploratory laparotomy in patients who may have multiple other injuries. PathophysiologyBowel injury can result from both blunt and penetrating trauma to the abdomen. Blunt trauma is the most common mechanism of injury to the bowel. Of patients with blunt abdominal trauma, 5% will have intestinal and mesenteric injury. Blunt trauma can occur from vehicular accidents, falls, and assaults. Penetrating trauma to the gut occurs more frequently in the urban setting and typically is secondary to knife or gunshot wounds.
FrequencyUnited StatesIn the United States, trauma is the leading cause of death in men and women younger than 40 years and is the third leading cause of death in all age groups. InternationalIn industrialized countries, trauma is the leading cause of death among individuals aged 1-40 years. Worldwide, 1 in 10 deaths occur from traumatic injuries. Specific statistics regarding trauma to the bowels is not available. Mortality/MorbidityThe abdomen is the third most commonly injured body region, and 10% of trauma deaths result from abdominal injuries. Morbidity and mortality in bowel trauma occur as a result of hemorrhage of injured mesenteric vessels or peritonitis from bowel wall rupture. SexOverall, males have a higher incidence of traumatic injuries than females. AgeTraumatic injury is the leading cause of death in males and females aged 1-40 years. AnatomyEach anatomic region of the GI tract is associated with characteristic patterns of injury. Most full-thickness gastric injuries result from penetrating trauma. Blunt abdominal gastric trauma occurs after a full meal. The most common site of gastric rupture is the anterior wall, followed by the greater curvature, the lesser curvature, and the posterior wall. Of duodenal injuries, 75% are secondary to penetrating trauma and 25% to blunt trauma. Blunt duodenal injury usually occurs in the second or third portion of the duodenum, where the duodenum can be compressed against the spine. Shearing injury also can occur adjacent to the ligament of Treitz. Duodenal injuries include duodenal wall hematoma, which can be managed without surgery, and duodenal wall rupture, which requires emergent surgery. Injury often occurs near points of fixation, such as the ligament of Treitz or ileocecal valve. Rupture often occurs along the antimesenteric border. Colonic injury can occur from both penetrating and blunt trauma. Blunt trauma frequently involves compressive injury to the transverse colon, the sigmoid colon, or the cecum. Clinical DetailsEvaluation of a patient with potential bowel trauma includes the following steps:
Swelling, bruising, skin penetration, lack of bowel sounds, guarding, and direct and rebound tenderness suggest the possibility of bowel injury. Clinical signs of bowel injury (ie, abdominal tenderness, rigidity, absent bowel sounds) are present in only 31% of patients. Preferred ExaminationCT of the abdomen is the preferred diagnostic examination for the evaluation of blunt abdominal trauma in the hemodynamically stable patient with blunt abdominal trauma and in selected instances of penetrating trauma to the posterior abdomen. Unstable patients or patients with penetrating injuries to the abdomen undergo exploratory laparotomy. Abdominal CT examination should be systematic.
Each imaging modality (eg, plain abdominal radiograph, US, CT) demonstrates typical findings that suggest a diagnosis of bowel trauma. In the hemodynamically stable patient with abdominal trauma, CT is the study of choice. Limitations of TechniquesThe accuracy of CT for the evaluation of bowel injury is as high as 97.6%. CT can be limited if DPL is performed prior to the CT. Free intraperitoneal fluid and air from the DPL observed on CT makes the evaluation for bowel injury very difficult. Although CT can suggest bowel injury by demonstrating free intraperitoneal air, free fluid, or thickened bowel wall, in many instances it cannot reliably localize the exact location of bowel injury. Delayed presentation of bowel injury occasionally occurs. Patients returning with continued symptoms several hours or days after a negative trauma should undergo repeat CT. DIFFERENTIALS
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Abdominal CT |
Direct Findings |
Indirect Findings |
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Bowel injury |
Bowel wall disruption and oral contrast extravasation |
Free intraperitoneal/retroperitoneal air, free intraperitoneal/retroperitoneal fluid
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Mesenteric vascular injury |
Intravenous contrast extravasation from the area of the mesentery |
Diffuse bowel wall thickening, diffuse bowel wall enhancement, mesenteric infiltration/mesenteric hematoma |
The accuracy of CT for evaluating bowel injury is 82%, with a sensitivity of 64% and a specificity of 97%.
Some findings on CT suggesting bowel injury can represent false-positive findings:
MRI has no role in evaluating patients with suspected bowel trauma.
Typically, the role of US in evaluating bowel trauma is limited to detecting free intraperitoneal fluid in trauma patients who are not sufficiently hemodynamically stable to undergo CT. However, the identified fluid cannot be further defined. Considerations include benign ascites, blood, urine, or bile and must be confirmed with CT.
Other findings of bowel injury include dilated bowel loops secondary to an ileus or obstruction. US is insensitive in detecting intraperitoneal free air.
Nuclear medicine has no role in evaluating acute bowel trauma.
The only role of angiography in acute bowel trauma is to identify the site of visceral bleeding.
Vascular intervention includes embolization of bleeding mesenteric vessels.
| Media file 1: A 47-year-old man with blunt trauma to the abdomen. Axial CT through upper abdomen reveals 2 spots of free intraperitoneal air (arrows). | |
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| Media file 2: A 15-year-old boy with blunt trauma to the abdomen and a perforated stomach. Axial CT demonstrates large amount of free intraperitoneal air (green arrow). An air/fluid level with fluid is seen in the right paracolic gutter (red arrow). Extravasated oral contrast is seen in the left paracolic gutter (blue arrow) adjacent to the stomach. | |
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| Media file 3: Patient in a motor vehicle collision with injury to the spleen. Axial CT through the abdomen shows thickening and enhancement of bowel wall in the left lower quadrant resulting from hypotension and hypoperfusion of the bowel. No bowel injury was seen. | |
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| Media file 4: Picture 4. A 47-year-old man with blunt trauma to the abdomen. Axial CT through the level of the pelvis shows small bowel wall thickening and enhancement (red arrow) from blunt small bowel injury. Free intraperitoneal air visualized (blue arrow) is from a perforated sigmoid colon. Image from AJR 2000;174:1538 printed with permission from American Roentgen Ray Society. | |
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| Media file 5: A 19-year-old man with right-sided chest trauma. Axial CT through the upper abdomen shows a large amount of right retroperitoneal air surrounding the right kidney (arrows). Some air is seen in the right subcutaneous tissues. Retroperitoneal air dissected downwards from a right-sided chest pneumothorax. | |
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| Media file 6: Patient with blunt abdominal trauma with duodenal hematoma. Axial CT through the abdomen shows soft tissue density and mild stranding surrounding duodenum (arrow) consistent with a duodenal hematoma. | |
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| Media file 7: Female patient with blunt abdominal trauma and duodenal perforation. Focal axial CT of the right upper abdomen shows free intraperitoneal air (red arrow) and contrast extravasation (blue arrow) from the duodenum (yellow arrow). | |
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| Media file 8: Female patient with right-sided colon perforation. Axial CT through the abdomen shows focal gas bubbles (red arrow) and anextraluminal fluid collection (blue arrow) adjacent to the contrast-filled colon. | |
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| Media file 9: A 79-year-old woman after a motor vehicle collision. Axial CT through the level of the pelvis shows a focal area of small bowel wall thickening (red arrow) consistent with focal blunt small bowel injury. Fat stranding is seen in the mesentery (yellow arrow) consistent with a mesenteric hematoma. | |
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| Media file 10: A 24-year-old man with blunt abdominal trauma and duodenal hematoma. Upper gastrointestinal series of the region of the duodenum shows large filling defect (arrow) compressing the contrast-filled second portion of duodenum lumen. Findings are consistent with an intramural duodenal hematoma. No extravasation of contrast is observed that suggests duodenal perforation. | |
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Article Last Updated: Sep 2, 2005