Emergency CT Scanning of Trauma Patients

Multislice computed tomography (MSCT) is playing an important role in emergency departments (ED). This and other emerging ED imaging trends were discussed in a course held during the annual meeting of the European Congress of Radiology (ECR) in Vienna (Austria), led by Christoph D. Becker, professor of radiology at University Hospital, Geneva (Switzerland) and Pierre Schnyder, professor of radiology at University Hospital, Lausanne (Switzerland). A summary follows.

Whole-body CT is becoming increasingly popular for managing trauma patients because it provides a fast evaluation in a single exam and is also the best choice for detecting abdominal injuries in blunt trauma patients. This helps doctors to minimize surgery, operating only when necessary. CT is also the most comprehensive modality for imaging patients with aortic, spine, or cranio-cerebral trauma, allowing doctors to quickly evaluate the severity of injuries. However, radiologists need to modify their methods of reading images and generating reports for best results of MSCT in an emergency setting, where the trend is towards two- and three-dimensional reconstruction protocols. Radiologists also need to adjust their scanning techniques to handle patients with multiple trauma. CT scanning for trauma employs an injury scale that differs from that used by surgeons, which can make it difficult to compare data from the two techniques.

"The CT scale correlates well with outcomes for liver and kidney trauma, but it is still controversial for the spleen,” said Prof. Schnyder. "The good thing about it, though, is that it makes studies from different centers comparable because CT is used widely for trauma patients around the world.” Prof. Schnyder noted that the intrasplenic "contrast blush” of CT is a strong indicator that conservative treatment may fail and that surgery may be necessary.

CT also has a high sensitivity for detecting parenchymal splenic and hepatic injuries. With careful scanning techniques and interpretation, sensitivity for detecting injuries caused by gastrointestinal trauma is also good. Patients who are treated conservatively need repeat CT studies, according to Prof. Becker. These follow-up scans can provide early detection of delayed, clinically silent complications such as post-traumatic biloma or bowel devascularization.

Despite these many benefits, ultrasound will likely remain the modality used for many blunt trauma patients, to determine if other imaging studies are needed. Ultrasound is especially good for patients with abdominal trauma and should be the initial screening tool for suspected abdominal hemorrhage. "With ultrasound, you can quickly see which patients are hemodynamically unstable and refer them for emergency laparotomy,” said Prof. Becker. "However, even with experienced scanners, ultrasound is not reliable enough to rule out organ injuries.”