Carotid & Vertebral Artery Injuries

1. Carotid & Vertebral Artery Injuries Chapter 70

2. Controversies • Pros and cons of duplex versus angiography versus newer modalities • Selective versus mandatory exploration for penetrating Zone II injuries • Treatment of patients with coma • Blunt carotid injury

3. Penetrating Carotid Artery Trauma • Epidemiology • Young, healthy, intoxicated males • Stab wounds & low velocity missiles • 6% of penetrating neck injuries • 22% of all cervical vascular injuries • CCA>ICA • Iatrogenic trauma during central line placement

4. Evaluation of Patients with Penetrating Trauma • Hard signs of vascular injury • 8-25% of patients with penetrating neck injury • Shock • Active bleeding • Expanding hematoma • Require expeditious operative exploration • Soft signs of vascular injury • Majority of patients • History of pulsatile bleeding • Small, stable hematoma • Cranial nerve injury • Unexplained neurologic deficit • “Proximity” injury without other signs

5. Penetrating Neck Trauma • Injuries not penetrating the platysma are superficial and require no further workup • Zone III • Angle of mandible to base of skull • Exposure of this area difficult • Pharynx; distal carotid and vertebral arteries; parotid gland; cranial nerves • Zone II • Cricoid to angle of mandible • Usually clinically apparent injuries • Cartoid and vertebral arteries; jugular vein, larynx; esophagus; trachea; vagus; recurrent nerve • Zone I • Thoracic inlet (sternal notch to cricoid) • Injuries to this area have highest mortality • Proximal carotid, subclavian, vertebral arteries; upper lung; esophagus; trachea; CNS

6. Initial Management • Airway • Endotracheal intubation for any difficulty with oxygenation, ventilation, or depressed sensorium • Obvious tracheal injury can be treated with ETT into the wound • Bleeding controlled with direct pressure • CXR and lateral C-spine films • Major vascular injury in Zone II usually clinically apparent with significant hematoma or frank external hemorrhage • Approached by immediate surgical exploration • Due to difficulties of vascular exposure in Zone I and III, angiography is needed prior to surgical exploration unless extremely unstable

7. Physical exam normal • No hypotension, active bleeding, unequal UE pulses, expanding neck hematoma, motor function abnormalities, clavicular fracture, SQ air, stridor, nor voice abnormalities

8. Proposed algorithm for Zone I injury

9. MANDATORY Low rate of complications with exploration (2.2% and 0%) Potentially devastating effect of delay in diagnosis of aerodigestive injuries Unreliability of physical signs for predicting cervical vascular injury SELECTIVE High rate of negative exploration (40-60%) Low incidence of devastating complications of delaying therapy CONTROVERSY:Optimal approach for patients with Zone II injuries • Current data shows similar outcome for both approaches • Selective management include various combinations of physical examination, triple endoscopy, angiography, esophagography, CT scanning, duplex

10. Zone II Injury Selective Workup • Demetriades et al, Br J Surg ’93 • 176 stable patients undergoing arteriography • 19% with vascular injury, 8% requiring intervention (all were symptomatic) • Low yield for arteriography in asymptomatic patients • Fry et al, Am J Surg ’94 • 100 stable patients evaluated • 15 underwent DUS then arteriography • 1 arterial injury found on DUS confirmed on arteriography • Remaining 85 had arteriography only when DUS abnormal • 7 arterial injuries found on DUS confirmed • 2 venous injuries • Remaining 76 patients with normal DUS were stable • Frykberg et al, J Vasc Surg ’00 • 145 prospective injuries studied • 91 patients with isolated Zone II injuries observed without sequelae • 23 patients underwent arteriography with 3 injuries • Missed injury rate 0.9%

11. CT-A for Neck Injury • Gonzalez, et al. J Trauma ‘03 • 42 prospective patients with Zone II underwent CT + esophagography, then exploration • 4 esophageal injuries (2/4 on CT, 2/4 on esoph) • 7 IJ injuries (4/7 on CT) • Gracias, et al. Arch Surg ‘01 • 23 patients with penetrating neck injuries underwent CT initially • 13 patients no injury (4 discharged from ED) • 10 patients had angiography, 2 required endoscopy due to proximity • Mazolewski, et al. J Trauma ‘01 • 14 prospective patients with Zone II injuries underwent CT, then mandatory exploration • 4 scans deemed high probability, 3 had surgical injury • No missed injuries • Munera, et al. Radiology ‘02 • 175 patients with penetrating neck injuries • Injuries idenitified in 27 patients (15.6%), observation in 146 • Sensitivity 90%, specificity 100%, PPV 100%, NPV 98% • One missed injury of pseudoaneurysm at common carotid origin

12. Surgical Management • All significant penetrating carotid artery lesions should be repaired when technically feasible • Primary repair • Patch angioplasty • Internal-to-external carotid artery transposition • Interposition graft • Controversy surrounds carotid injuries to patients with coma • Initial anecdotal reports of conversion of ischemic infarcts to hemorrhagic infarcts • Recent evidence that most deficits remain unchanged or improve • Collected series • 28 comatose patients treated with ligation (61% mortality, 14% good outcome) • 42 comatose patients repaired (26% mortality, 50% good outcome) • Minor carotid injury (intimal defect or small pseudoaneurysm) • Nonoperative management in neurologically intact patients safe

13. Outcomes/Future Directions • Mortality 17% • Stroke rate 28% • Higher if coma or shock present (50% & 41%) • Endovascular case reports for Zone I and III injuries

14. Blunt Carotid Artery Trauma • Accounts for 3-10% of carotid injury • 4 mechanisms • Cervical hyperextension-rotation (most common) • Direct blow to the neck • Intraoral trauma • Basilar skull fracture • Injuries results in dissection, thrombosis, pseudoaneurysm formation, carotid-cavernous sinus fistula, complete disruption • Distal ICA>CCA (90%:10%)

17. Diagnostic Evaluation • Diagnosis of blunt carotid injuries increased due to heightened awareness and more aggressive screening • Fabian et al, Ann Surg ’96 • 96 cases reported up to 1980, 75 cases in 80s, 309 cases from ’90-’95 • Optimal screening modality not established • 4 vessel cerebral angiograms not cost-effective • DUS has difficulty with high ICA lesions • CT-A (Berne et al, J Trauma ’04) recently thought to be best screening test

18. Grading System • Grade I: mild injury • Most (66%) heal even without treatment • Grade II: dissection or hematoma with luminal stenosis • Grade III: pseudoaneurysm • Grade IV: carotid occlusion • Grade V: transection • Usually lethal and not amendable to treatment

19. Treatment/Outcomes • Carotid-cavernous sinus fistulae • Balloon occlusion techniques • Dissection, thrombosis, pseudoaneurysm have varied approaches • Recent literature supports nonsurgical management for dissections and thrombosis • Systemic heparinization followed by 3-6 mo coumadin • Pseudoaneurysms should be surgically repaired • Prognosis is generally poor • Mortality rates 5-43% • Good neurological outcomes in only 20-63% of survivors

20. Vertebral Artery Trauma • Exceedingly rare • 2 largest series have 43 and 47 patients • Clinical presentation and outcomes related to associated injuries • 70-80% of patients with vertebral artery injury have no evidence of arterial trauma on exam • Usually diagnosed on angiography or CT-A for neurologic deficits • Most injuries (AV fistulae and pseudoaneurysms) can be managed with proximal and distal artery occlusion • Surgical ligation versus endovascular coiling • Vertebral occlusion can be observed • Occasionally some risk of rebleeding • Arterial repair reserved for rare circumstance when preoperative arteriography suggest inadequate collateral circulation

21. Major Venous Trauma • Operative exposure for venous injuries should follow adjacent arteries/arterial injuries • Severe injuries to innominate, IJ, subclavian veins can be ligated • Definite treatment option for unstable patients or those with significant other injuries • Lateral venorrhaphy can be attempted if >50% luminal size • SVC or bilateral innominate/IJ injuries can be considered for repair to prevent SVC syndrome or acute cerebral edema

22. Summary • Hard signs of vascular injury mandate operative exploration • Good results can be obtained with mandatory exploration, routine arteriography or DUS or CT-A, or physical examination alone in properly selected patients • Adopted approach should be based on experience, volume, local diagnostic capabilities, and personnel resources • All significant penetrating carotid artery lesions should be repaired when technically feasible • Diagnosis of blunt carotid injury requires high index of suspicion, but optimal screening tool remains controversial • Nonsurgical treatment and anticoagulation is the mainstay of treatment for most blunt carotid injuries • Vertebral artery injuries are rare and treated by exclusion of the injured artery from the posterior circulation