Thoracic Vascular Trauma Gan Dunnington MD Stanford University 10/17/05.
Post on 27-Dec-2015
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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
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