Health Care Policy

pact on the care of the patient from diagnosis of the injury to therapeutic options including stents or stentgrafts. Blunt trauma to the chest and neck often causes unrecognized injUries to the brachiocephalic arteries and veins. Originally, these injuries were thought to occur in less than 1% of blunt trauma cases. However, recent data suggest that carotid injuries occur 3 to 5 more frequently (1). In as many as 30% of these injuries, there are bilateral carotid dissections. These injuries are not as rare as originally reported because of both the use of seat belts and the more aggressive use of diagnostic techniques to discover the injuries. These facts dictate that any patient sustaining blunt trauma to the neck and chest or a basilar skull fracture should be considered a candidate for carotid dissection. The mechanism of injury is the stretching of the extracranial internal carotid artery over the lateral mass of the first cervical vertebra because of a hyperextension injUly with rotation. These injuries will usually begin at the bifurcation of the common carotid artery and extend to the base of the skull. Uncommonly, an initial pseudoaneurysm will arise at the entrance of the internal carotid artery into the base of the skull without a preexisting dissection. The latter injury only occurs with significant energy deposition in the skull base with an associated basilar skull fracture. The conventional treatment of choice is anticoagulation because carotid arterial dissections will usually heal without additional intervention. However, extension of the dissection throughout the extracranial internal carotid artery with narrowing of the lumen of the vessel suggests that more aggressive treatment should be considered because of the probability of thrombotic embolic events even with adequate anticoagulation. It has been shown that once a pseudoaneurysm has developed, it will not spontaneously thrombose and may be the source of cerebral emboli (2). Blunt trauma rarely causes venous injury. The exception is in strangulation injuries that can occlude the internal jugular veins. These injuries are life threatening because an increase in intracranial pressure will result. Use of stents in the internal jugular vein will adequately treat these injuries if thrombolytic agents are not effective. Penetrating trauma will cause very localized injuries as in the passage of a bullet or knife. However, with the larger caliber weapons, especially military-type high velocity rounds, the blast or concussive effect of the shock wave passing through tissues will widen the area of injury. Embolization of hemorrhaging vessels is indicated to stabilize the patient before surgery or as definitive therapy especially in the neck, shoulder, or groin because of the difficulty of surgical exploration. Knowledge of the patency of the circle of Willis is essential before embolization of the carotid or vertebral arteries is performed. Use of coils will all the efficient closure of the bleeding vessels.

In summary, the use of transcatheter methods for treatment of arterial and venous brachiocephalic injuries is an important adjunct to surgical therapy, but adequate knowledge of the mechanism of injury, wounding patterns, and surgical options are essential to optimize the role of interventional radiology in the treatment of these patients.

Selected Bibliograpy 1. Fabian TC, Patton ]H, Croce MA, et al. Blunt carotid injury. Importance of early diagnosis and anticoagulant therapy. Ann Surg 1996; 223:513-522. 2. Welling RE, Kakkasseril ]S, Peschiera]. Pseudoaneurysm of the cervical internal carotid artery secondary to blunt trauma.] Trauma 1985; 25:1108--1109.

10:55 am Health Care Policy Speaker to be Announced 11:25 am Current Management of Abdominal Trauma Michael Katz, MD Leanting objectives: (1) To describe recent changes in

abdominal trauma management algorithms; (2) to understand the role of the interoentional radiologist in the management of abdominal trauma; and (3) to be familiar with the principles of visceral embolization. ABDOMINAL trauma most commonly results in injury to the solid parenchymal organs. Triage of abdominal trauma is based on the mechanism of injury and hemodynamic status. Alterations in the surgical management of these injuries has changed referral patterns for arteriography. Unstable patients undergo emergency laparotomy. Massively traumatized patients may be treated by "damage control" surgery solely for control of hemorrhage and enteric contamination. Repeat exploration at 48-72 hours is performed for definitive repairs. By abbreViating the initial surgery, patients can be aggressively treated for hypothermia and coagulopathy, and hemodynamics can be optimized. After or between surgeries, additional bleeding is best managed by arteriographic embolization. Whereas unstable patients undergo emergency laparotomy, stable patients undergo radiologic evaluation, usually by CT. Computed tomography has the pivotal role in abdominal trauma triage. Abdominal arteriography is therefore rarely used as the initial diagnostic modality, but can be combined with emergency pelvic or thoracic arteriography in the polytrauma patient. A limitation of CT is that it does not readily differentiate active bleeding from bleeding that has already stopped. However, advances in CT technology that allow for more rapid scanning have increased the frequency of identifying contrast extravasation. A characteristic focal high-density area, isodense with major ar-