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Thoracic Vascular Trauma. Gan Dunnington MD Stanford University 10/17/05. Thoracic Vascular Trauma. Thoracic Injuries account for 25% of death due to trauma Majority of penetrating chest trauma managed by tube thoracostomy
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Thoracic Vascular Trauma Gan Dunnington MD Stanford University 10/17/05
Thoracic Vascular Trauma • Thoracic Injuries account for 25% of death due to trauma • Majority of penetrating chest trauma managed by tube thoracostomy • Thoracic vascular injuries have high mortality in pre-hospital setting • Trauma center data (Mattox et al. 1989) • Of 5760 civilian vascular injuries over 30 yrs • 168 subclavian art, 190 carotid, 39 innominate, 144 thoracic aorta • 90% due to penetrating trauma
Prehospital • >80% blunt aortic injury die at scene • Prevention – seatbelts, airbags, driving habits • EMS – • IVF, intubation, defibrillation, cardiac drugs, EKG – effective for cardiac arrest • Immediate transport necessary • Assessment of mechanism of injury
Assessment • History • Steering wheel impact • Automobile deformation • Fall from significant height • Aircraft accident • Death of another passenger in same vehicle • Ejection
Assessment • Physical • Intrascapular murmur • Pulse/pressure defecit • T-spine fracture • Sternum/clavicle/scapula fracture • Hematoma of thoracic outlet
Assessment • Imaging • CXR • Hemothorax, tracheal displacement, fractures of sternum/clavicle/scapula, loss of aortic knob, mediastinal widening, thoracic outlet hematoma, deviation of left mainstem bronchus or NG tube, foreign bodies, out of focus foreign body
Assessment • Imaging • CT scan (CT Angio) • Probably imaging modality of choice • Transesophageal Echocardiography • Descending aorta • Difficult to image arch • Operator dependent
Assessment • Imaging • Arteriography • “gold standard?” • Beware anatomic variants • Ductus bump • Ulcerative plaque • Multiple views required • MRI/MRA • Not practical in acute trauma patient
Preop • Type and Cross in trauma bay • Cell-saver • IV access contralateral to injury, above and below diaphragm • Avoid Right IJ in descending aorta injury? • Double lumen endotracheal tube • Permissive hypotension before vascular control achieved
Operative Therapy • Incisions • ER thoracotomy • Left anterolateral clamshell • Sternotomy • Ascending aorta, arch, innominate, right subclavian, left common carotid • May be extended into left/right neck • High 3rd interspace anterior thoracotomy • Left subclavian proximal control • Supraclavicular incision • Posterolateral thoracotomy • Descending aorta
Operative Therapy • Communication with anesthesia and perfusionists is essential • Graft selection • Knitted vs woven, Dacron vs. PTFE • Shunting • Clamp-and-sew vs. mechanical perfusion • Paraplegia with clamp-and-sew approx 15% • Cardiopulmonary bypass requires full anticoagulation • Atrial-femoral bypass with centrifugal pump • Decreases paraplegia rate to 3%
Thoracic Aorta • Penetrating trauma • 50% mortality • Ascending –stab wounds • Descending – gunshot wounds • Blunt trauma • Ascending aorta trauma – 85% mortality • Cardiopulmonary bypass, cardioplegia
Thoracic Aorta Arch • Usually involve takeoff of innominate artery • Can be managed with Ao-innominate graft, oversew arch using side-biting clamps • Mortality 26% Shin et al. J trauma 2000
Descending Thoracic Aorta • Proximal control between carotid and subclavian • Know patient’s arch anatomy • Do not debride aorta • Do not sacrifice intercostals • Move clamps closer to injury when identified • Use fine suture and a soft graft • 85% repairs require interposition graft • If less than 50% circumference, may fix primarily • Mortality of managing blunt descending trauma approximately 30%
Descending Thoracic Aorta • Mattox and Wall classification • Category 1 • Massive injuries, exsanguination at scene, surgical repair futile • Category 2 • Present to ER with unstable hemodynamics and transient response – may be time for imaging • Category 3 • HD stable, contained hematoma, injury found with screening, may be transferred to aortic centers
Descending Thoracic Aorta • If delay: • Afterload reduction, dP/dT reduction • Betablockers, SNP • Keep MAP below preinjury level • Mediastinal hematoma must be stable on serial imaging • Patient informed of risks • Supervised by a surgeon • Optimal to perform surgery within 72 hrs of injury
Brachiocephalic Vessels • Incision dictated by injury • Sternotomy, clamshell, left thoracotomy, supraclavicular • Left subclavian can be ligated • Follow with carotid-subclavian bypass if needed • Subclavian vessels well collateralized and usually require graft due to soft vessel
Pulmonary vessels • Uncommon injury • Proximal injuries usually found when exploring hemopericardium • May be fixed primarily or require CPB • Distal injuries may require lobectomy/pneumonectomy • Penetrating lung injury – • Tractotomy and ligation of bleeders air leaks
Vena Cavae • Intrathoracic Cavae rarely injured –short • Pericardial tamponade usually found • Lateral venorrhaphy • Short inflow occlusion may be used • Interposition grafts for extensive injury • CPB can be necessary at times • Azygous injury mortality similar to caval injury • May be ligated/oversewn
Miscellaneous vessels • Intercostal injury • May loop rib with heavy absorbable suture • Mammary artery injury • Clamshell thoracotomy
Post-op care • Most require ICU care • Rewarming, correction of coagulopathy • Minimize crystalloid infusions if possible to limit pulmonary edema • Thoracic epidurals for pain management
Endovascular care • Numerous series – retrospective with trends towards efficacy • Rousseau et al. JTCVS. 2005. France • 76 pts admitted 1981-2003 with traumatic aortic injury • 35 treated surgically, 7 delayed (avg. 66 days) • Mortality/paraplegia = 21%/7% • No death or paraplegia in delay group • 29 stent grafted at isthmus • No major morbidity, no mortality in stent graft group at 46 months follow up
Endovascular care • Under investigation • Allows avoidance of morbid thoracic incisions • May allow delayed repair • May cover left subclavian artery with stent-graft • Results are equal to open surgery in short-term follow up
Summary • Injuries to thoracic aorta often fatal at scene • Hemodynamically unstable patients require emergent thoracotomy • Careful consideration needs to be given to incision • Adjuncts of shunts, grafts, CPB often necessary for surgical repair • Emerging role for endovascular therapy
Reference • Wall M, Huh J, Mattox K. Thoracic Vascular Trauma. Vascular Surgery; 2005: 71: .