Arteriovenous Fistula Is Protective in Stab Wounds Involving Major Vessels

Abstract

<h3>Introduction and Objective</h3> Stab wounds to the neck resulting in major vascular injuries occur in 40% of patients. These are usually associated with significant blood loss and frequently fatal. We describe a patient with multiple stab wounds to neck resulting in almost complete transection of the right common carotid artery (CCA) with a large pseudoaneurysm and an associated internal jugular (IJ) injury, resulting in a "protective" arterio-venous (AV) fistula. Protective AV fistulae are uncommonly described in the literature. We believe this to be a novel description of a CCA transection with associated "protective" AV fistula. <h3>Case Report</h3> A middle-aged male presented to our Level I trauma center after suffering three 1 cm stab wounds to the right side of his neck. The patient arrived via ambulance. The emergency medical services crew provided basic field care including applying supplemental oxygen and covering wounds with dry gauze. Upon arrival, the patient was verbal with a Glasgow Coma Scale score of 15. Heart rate was 122 and blood pressure was 139/91. On initial examination, a large, pulsatile hematoma with a palpable thrill was noted underlying a laceration to the lateral aspect of zone two. A second and third laceration were noted without associated swelling in zone one and zone three, respectively. Minimal external bleeding was noted from all stab wounds. Computed tomography angiography was obtained en-route to the operating room and demonstrated a right CCA injury with a large pseudoaneurysm and AV fistula decompressing into the right internal jugular (IJV) vein. On operative exploration, the right CCA was found to be greater than 90% transected with the proximal and distal ends connected by small amount of bridging adventitia. The right IJV was found to have an approximately 70% wall transection and the vagus nerve was totally transected. The CCA and IJV were repaired in a primary end-to-end fashion. The vagus nerve was also repaired. The patient had an uneventful postoperative course and was discharged home on hospital day three. On follow-up visit after 6 weeks patient was doing well with no neurovascular deficit. <h3>Discussion</h3> Penetrating injuries of the neck involving major vessels are associated with high morbidity and mortality. A traumatic AV fistula can provide a protective effect by decompressing the injured arterial structure and prevent massive blood loss and airway compression. Protective AV fistulae have been uncommonly described, and to our knowledge, this is the first case involving a >90% carotid transection with associated "protective" AV fistula ultimately allowing life-saving operative repair.