Is hepatic artery pseudoaneurysm a recognized complication of pancreaticoduodenectomy (Whipple) in a young adult with multifocal pancreatic head neuroendocrine tumors and comorbid diabetes mellitus, hypertension, and thyroid disease?

Hepatic Artery Pseudoaneurysm After Pancreaticoduodenectomy

Yes, hepatic artery pseudoaneurysm is a well-recognized and potentially life-threatening complication of pancreaticoduodenectomy (Whipple procedure), occurring in approximately 4.9% of patients and carrying a mortality rate of up to 27-50% when rupture occurs. 1, 2, 3

Incidence and Clinical Significance

• Pseudoaneurysm formation after pancreaticoduodenectomy occurs in approximately 4.9% of patients, with the hepatic artery being one of the most common sites (36% of cases in one series) 2
• The median time from surgery to detection is 17 days (range 1-76 days), though delayed rupture has been reported as late as 120 days postoperatively 2, 4
• Approximately 72.7% of patients with pseudoaneurysms present with hemorrhage, and mortality from rupture ranges from 27.3% to 50% 1, 2, 3

Pathophysiology and Risk Factors

The formation of pseudoaneurysms results from several mechanisms specific to pancreaticoduodenectomy:

• Postoperative pancreatic fistula is an independent risk factor (p=0.013), as pancreatic enzymes cause local tissue digestion and arterial wall erosion 2
• Intra-abdominal collections and local inflammatory processes create an environment conducive to vessel wall breakdown 1
• Prolonged operating time is a significant independent risk factor: operations exceeding 610 minutes increase pseudoaneurysm risk (p=0.026), and those exceeding 657 minutes significantly increase mortality from rupture (p=0.043) 2
• Younger age (<65.5 years) paradoxically increases risk (p=0.004) 2
• Arterial wall weakness from extensive lymphadenectomy and skeletonization during dissection, particularly around the hepatic artery and superior mesenteric artery 4, 5

Clinical Presentation and Warning Signs

Recognize these prodromal symptoms that often precede rupture:

• Upper abdominal oppression, nausea, and backache are warning signs that should prompt immediate investigation 3
• Persistent fever, leukocytosis, hyperbilirubinemia, anastomotic leak, and intra-abdominal abscess are frequent accompanying signs 3
• Upper gastrointestinal bleeding unresponsive to conservative treatment with hemodynamic instability indicates likely pseudoaneurysm rupture 1

Diagnostic Approach

• When warning signs appear in the postoperative period, perform immediate diagnostic angiography rather than waiting for frank hemorrhage 3
• Color Doppler ultrasound can identify pseudoaneurysms and should be used for screening in high-risk patients 4
• CT angiography provides definitive anatomic localization when pseudoaneurysm is suspected 1

Management Strategy

Transcatheter arterial embolization (TAE) is the first-line treatment and achieves complete hemostasis in 85% of cases:

• Emergency angiography with TAE should be performed immediately upon diagnosis or hemorrhagic presentation 3
• TAE achieves complete hemostasis in 11 of 13 patients (85%) in reported series 3
• Embolization of the common hepatic artery proximal and distal to the pseudoaneurysm with microcoils is the standard technique 4
• Surgical hemostasis should be reserved for cases where TAE fails to achieve complete hemostasis 3

Critical Pitfalls and Complications

Be aware of these specific complications of hepatic artery embolization:

• Biliary ischemia and intrahepatic biloma can occur when hepatic arterial flow is interrupted, as the bile duct blood supply is compromised after pancreaticoduodenectomy 6
• Minor transient elevation of liver enzymes is expected and typically resolves 4
• Patients who undergo surgical hemostasis after failed TAE have high mortality from multiple organ failure (MOF) 3
• Avoid initial surgical exploration without angiography, as this approach is associated with higher mortality (43 days to death from MOF in one case) 3

Prevention Strategies

Based on identified risk factors, implement these preventive measures:

• Minimize operating time through efficient surgical technique and adequate preoperative planning 2
• Protect vessels during dissection and ensure adequate hemostasis intraoperatively 1
• Aggressively prevent and treat postoperative pancreatic fistula, as this is the most modifiable risk factor 2
• Ensure nutritional repletion preoperatively 1
• Treat intra-abdominal infections and collections promptly 1, 3

Surveillance in High-Risk Patients

Maintain high clinical suspicion in patients with:

• Prolonged operating time (>610 minutes) 2
• Postoperative pancreatic fistula 2
• Persistent fever, leukocytosis, or intra-abdominal collections 3
• Age <65.5 years 2

In these patients, any prodromal symptoms (upper abdominal oppression, nausea, backache) should trigger immediate diagnostic angiography rather than watchful waiting 3.