Vascular: AAA Repair

Selection of Approach

• Transperitoneal Approach:
  • More Rapid Access (Best in Emergencies)
  • Better Access to Right Renal Artery
  • Better Access to Iliac/Femoral Arteries
• Retroperitoneal Approach:
  • Better Access to Visceral & Supraceliac Aorta
  • Better Access to Left Renal Artery
  • Avoids Adhesions from Prior Operations
• Controversy if Equivalent or Lower Complications with Retroperitoneal Approach

Transperitoneal Approach

• Position: Supine & Arms Abducted
• Exposure:
  • Midline Incision
  • Retract Transverse Colon Cephalad
  • Retract Small Bowel to the Right
  • Divide the Ligament of Treitz & Retract Duodenum to the Right
    • Avoid Injury to IMV
  • Incise Posterior Peritoneum from Ligament of Treitz Down to the Extent Necessary for Repair
    • Angle to the Right of Aortic Midline to Avoid Injury to IMA
  • If Suprarenal Clamp Needed – Open Posterior Peritoneum Up to the Level of the Renal Veins
    • May Require Renal Vein Division (Divide Close to IVC to Allow Collateral Drainage Through Gonadal, Adrenal & Lumbar Veins)
• Repair:
  • Systemic Heparinization
  • Clamp Iliacs Distally & Proximal Aorta
    • Distal First to Prevent Thrombus Embolization from Proximal Clamp)
  • Incise an Aortotomy Longitudinally with a T-Shape on Either End
  • Preform Proximal End-to-End Anastomosis
    • First Clear Anastomotic Sites of Thrombus
  • Clear Thrombus from the Aneurysmal Sac
  • Preform Distal End-to-End Anastomoses
    • First Clear Anastomotic Sites of Thrombus
    • Allow Flushing of Graft & Back-Bleeding Before Completing the Anastomoses
• Closure:
  • Achieve Hemostasis
  • Close Aneurysmal Sac Over the Graft
  • Close Posterior Peritoneum
  • Use Omentum to Separate Graft from Bowel if Unable to Close Sac or Peritoneum
    • Prevents Future Aortoenteric Fistula
  • Close Abdominal Wall

Retroperitoneal Approach

• Position: Right Lateral Decubitus
• Exposure:
  • Curved Skin Incision
    • Start Along the 10^th Intercostal Space at the Posterior Axillary Line
    • Run onto the Abdomen Lateral to the Lateral Border of the Rectus Muscle
  • Bluntly Dissect Peritoneum Off the Abdominal Wall
  • Identify Left Psoas Muscle Retract Peritoneal/Retroperitoneal Contents Anteromedially
  • Identify & Protect Left Ureter
  • May Divide Left Diaphragmatic Crus to Better Access Supraceliac Aorta
• Repair:
  • Systemic Heparinization
  • Clamp Iliacs Distally & Proximal Aorta
    • Distal First to Prevent Thrombus Embolization from Proximal Clamp)
  • Incise an Aortotomy Longitudinally with a T-Shape on Either End
  • Resect the Left Renal Artery with a Small Portion of Surrounding Aorta for Later
  • May Preform Endarterectomy or Deploy Stent in Stenosed Celiac or SMA
  • Preform Proximal End-to-End Anastomosis
    • Proximal End Must Be Beveled to Include the Celiac, SMA and Right Renal Artery
    • First Clear Anastomotic Sites of Thrombus
  • Anastomose Left Renal Artery Back to a Side-Branch of the Graft
  • Migrate Proximal Clamp Below the Renal Arteries to Minimize Ischemia Time
  • Clear Thrombus from the Aneurysmal Sac
  • Preform Distal End-to-End Anastomoses
    • First Clear Anastomotic Sites of Thrombus
    • Allow Flushing of Graft & Back-Bleeding Before Completing the Anastomoses
• Closure:
  • Achieve Hemostasis
  • Return Peritoneal Sac to Normal Configuration
  • Close Abdominal Wall

Specific Vessel Considerations

• IMA Reimplantation Indications:
  • SMA Stenosis
  • Large IMA
  • Backpressure < 40 mmHg (Poor Collaterals)
  • Previous Colectomy (Risk Injury to Collaterals)
• Lumbar Arteries:
  • Ligate if Bleeding