Carotid & Vertebral Artery Injuries Chapter 70

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

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

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

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

Initial Management Airway Bleeding controlled with direct pressure 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

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

Proposed algorithm for Zone I injury

CONTROVERSY: Optimal approach for patients with Zone II injuries 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 Current data shows similar outcome for both approaches Selective management include various combinations of physical examination, triple endoscopy, angiography, esophagography, CT scanning, duplex

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%

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

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

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

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%)

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

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

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

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

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

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