Aortic Transection
Parma Nand
Outline
AORTIC TRANSECTION
Parma Nand
03 August 2006
INCIDENCE
• Blunt trauma - deceleration
- compression
- direct injury
• estimated 20% all MVA deaths due to
? declining
older patients
• major associated injuries
• relatively uncommon operative repair
Aortic injury in vehicular trauma.
Williams JS et al. ATS 1994:57;726-730
– 530 post mortems. 105 aortic injuries in 90 victims
– site of tear/transection
• 65% prox descending
• 14% ascending and arch
• 12% distal descending
• 9% abdominal aorta
– associated injuries
• 78% multiple rib fractures
• 61% liver lacerations
• 42% head injuries
• 42% first rib fractures
• 36% splenic lacerations
• 34% heart lacerations
• 28% sternal fractures
• 26% cervical spinal fractures
NATURAL HISTORY
• Majority dead at scene
• previous paper
• 94% dead within first hour
• 99% dead within 24 hours
? What happens to those admitted to hospital
Transection Images
DIAGNOSIS
• Spiral CT with contrast +/- 3 D reconst.
– diagnose injury
– define site of injury - determines approach
– no role for emergency OT with “blind” approach
– helpful to exclude cervical spine injury
• aortography where equivocal
• TOE has been used
Management
• Blood pressure control
SBP< 100mmHg
• documentation/management associated injuries
major intracranial/abdo bleed
neuro status - ? paraplegia
cervical spine
• timing of interventions
SURGICAL MANAGEMENT
Surgical Technique -open
• Double lumen tube
• high postero-lateral thoracotomy 4th space
• clamp above subclavian, subclavian, decending aorta - minimise distance
• partial tear - primary repair
• primary repair not possible - interposition graft
fragile aortic tissue
Spinal Cord Protection
• Artery of Adamkiewicz variable
• Clamp and sew
vs
• Passive shunt GOTT
• active shunts Left Heart Bypass
Partial CPB
• ENDOLUMINAL GRAFT
Performing Repair
Completed Repair
Traumatic Aortic Rupture: Twenty-year Metaanalysis of Mortality and Paraplegia.
von Oppell U.O. et al. ATS 1994; 58: 578-84
• Most reported series are small, relatively uncommon operation
• of the 1742 pts “salvageable” 1972-1992
• 179 died before opn 10.3%(0-62%)
• further 61 bleed out despite emergent opn 3.5%
• 117/ 1492 died intraop 6.7%
• 201 died post op 11.5%
Results According to Technique
deaths(15.3%) new paraplegia(10.2%)
S-AXCL 16 19.2
Shunt-Un 14.6 13.9
Shunt-AA 11.3 8.2
Shunt-LV 8.7 26.1
Passive 12.3 11.1
Active(no heparin) 9.9
C-P 11.9 1.7
HFVAB 0.0 0.0
Active (Heparin/CPB) 18.2 2.4
2.3
Total Perfusion 15 6.1
Influence of distal perfusion and clamp time on paraplegia
CONCLUSION
• Spiral CT, angiography where equivocal
• aggressive BP control
• diagnosis = cardiothoracic emergency
• hypotensive and active bleeding head/abdo = priority over aorta
• stable but potentially progressive pathology = priority over aorta
• aorta = priority over injuries non life threatening but needing opn
• prohibitive risk pts - delay repair/ conservative
• technique of repair dependant on individual case
• where open - active distal perfusion
Endovascular Stent Graft in Traumatic Aorta
• Very attractive minimally invasive
alternative
• Technically safe & feasible
• Allows avoidance of:
- Large, physiologically debilitating incisions
- major heparinization
- Aortic cross clamping & prolonged distal
Hypotension → significant reduction in paraplegia
Other Advantages of Endovascular Stenting
Allows safe management of cases
– traditionally considered delayed management better option
• Greater feasibility of repair in acute phase – enables earlier management of this preventing in-hospital ruptures/bleed
Potential/Theoretical Disadvantages
• Relatively new technique & technology
• Long-term fate/durability of these grafts unknown
• L Subclavian artery needs to be covered in
- large majority → Arm ischaemia ??
→ Vertebral artery ??
Ischaemia
• Endoleaks/migration
#4: T.S. 61 y.
• Diagnosis:
– Thoracic rupture
– Emergency laparotomy and splenectomy
– Angiogram
• R/ urgent stentgrafting
#5: F.B. 20 y.
• Diagnosis:
– Thoracic aortic rupture
– associated with liverrupture, small bowel rupture and femurfractures
• R/ delayed thoracic stentgraft
#6: J.B. 51 y.
• Diagnosis:
– Pseudoaneurysm
– 20y. After thoracic rupture with successfull surgical repair
– Admitted electively, becoming symtomatic
• R/ urgent repair
Conclusion
Endovascular Stent-Grafting
• Attractive minimally invasive alternative
• Long-term durability unknown
• Allows greater feasibility in multi-trauma patients
TIMING OF REPAIR
• Historical emergent theatre
• recent papers have questioned this approach
Blunt trauma to the Heart and Great Vessels
Pretre R, Chilcott M. N Eng J Med 1997; 336:9, 626 - 632
• “…Although good results are reported by those who advocate delaying repair by a few days, no evidence currently validates delaying the repair of aortic rupture beyond the time required for the evaluation and treatment of other emergency conditions…”
Passive Shunt
• 8 - 10 mm heparinised tube - GOTT
• difficult to determine flows
• no heparin
• arch to distal descending aorta
• double pledgetted pursestrings
? Sufficient flows for adequate distal perfusion
Surgical Technique
• Double lumen tube
• high postero-lateral thoracotomy 4th space
• clamp above subclavian, subclavian, decending aorta - minimise distance
• partial tear - primary repair
• primary repair not possible - interposition graft
fragile aortic tissue
Left Heart Bypass
- LA/FA Bypass
• systemic heparin/ standard circuit
• Heparin bonded circuit/ no systemic hepari
• LA/PA to descending aorta/ femoral artery
• cell saver
• can add oxygenator/heat exchanger to circuit
• flows 1.2l/m2 , MAP > 60mmHg lower body
• MAP > 90mmHg upper body.
Partial CPB
• Full heparinisation
• same cannulation as L. Heart Bypass
• add reservoir to circuit - blood/air interface
• easier return of shed blood
• option of converting to circ arrest
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Ministry of Health
