What are the steps of a proximal splenorenal shunt (PSRS) procedure for portal hypertension?

Proximal Splenorenal Shunt (PSRS) Surgical Steps

The proximal splenorenal shunt involves creating an end-to-side anastomosis between the proximal splenic vein (after splenectomy) and the left renal vein to decompress portal hypertension, particularly effective in non-cirrhotic portal hypertension patients with refractory variceal bleeding. 1, 2

Preoperative Preparation

• Cross-sectional imaging (CT or MRI angiography) is mandatory to evaluate splenic vein anatomy, left renal vein position, and identify any anatomical variations that would preclude standard PSRS 1
• Assess coagulopathy using thromboelastography rather than INR, as INR is unreliable in liver disease; correct if indicated 3
• Platelet transfusion should be considered if platelet count is <50×10⁵/L 3
• General anesthesia or deep sedation with propofol is required 3
• Prophylactic antibiotics are recommended for complex procedures 3

Surgical Technique Steps

1. Patient Positioning and Incision

• Position patient supine with left side slightly elevated 2
• Perform midline laparotomy or bilateral subcostal incision for adequate exposure 2

2. Splenectomy

• Mobilize the spleen by dividing the splenocolic and splenorenal ligaments 2
• Ligate short gastric vessels and left gastroepiploic vessels 2
• Divide splenic artery first to reduce splenic engorgement and facilitate dissection 2
• Carefully dissect and preserve the splenic vein at its junction with the portal vein, ensuring adequate length (minimum 3-4 cm) for tension-free anastomosis 1, 2
• Ligate and divide the splenic vein at its confluence with the superior mesenteric vein, preserving maximum length 1

3. Left Renal Vein Exposure

• Mobilize the pancreatic tail medially to expose the left renal vein 1
• Identify the left renal vein anterior to the aorta and posterior to the superior mesenteric artery 1
• Dissect the left renal vein circumferentially for 2-3 cm to allow for anastomosis 1
• Ligate adrenal and gonadal tributaries if necessary to improve mobility 1

4. Anastomosis Creation

• Clamp the left renal vein with vascular clamps (partial occlusion or complete depending on anatomy) 2
• Create venotomy on the superior aspect of the left renal vein, sized to match the splenic vein diameter 2
• Perform end-to-side anastomosis between the proximal splenic vein and left renal vein using continuous 5-0 or 6-0 polypropylene suture 2
• Ensure tension-free anastomosis without kinking or twisting of vessels 1
• Release clamps sequentially (renal vein first, then splenic vein) and assess for hemostasis 2

5. Hemostasis and Closure

• Verify shunt patency by palpating thrill over the anastomosis 2
• Measure portal pressure pre- and post-shunt if equipment available; target reduction of portal pressure by at least 20% or to <12 mmHg 3, 4
• Achieve meticulous hemostasis given the pressurized venous system 3
• Place drains in the splenic bed and near the anastomosis 2
• Close abdomen in standard fashion 2

Technical Considerations and Alternatives

• If left renal vein is aberrant or unsuitable, consider splenoadrenal shunt (direct anastomosis to adrenal vein) as an alternative, which shows good results with median portal pressure reduction of 12.1 mmHg 1
• If splenic vein is narrowed or thrombosed, interposition mesocaval shunt or interposition PSRS using vein graft may be required 1
• Mean operative time is approximately 4.2 hours with expected blood loss of 450-500 mL 2

Postoperative Management

• Doppler ultrasound at one week post-procedure to assess shunt patency, particularly in patients with prothrombotic conditions 3, 4
• Follow-up Doppler ultrasound at 6-12 month intervals 3, 4
• Upper endoscopy at follow-up to evaluate variceal regression 1
• Monitor for hepatic encephalopathy, though rates are lower with PSRS compared to total shunts (17-28% in studies) 5

Expected Outcomes

• Shunt patency rates of 89-93% at long-term follow-up 1, 5
• Variceal rebleeding rates of 32-34% 5
• Complete resolution of hypersplenism in all patients 2
• No development of hepatic encephalopathy in most series of non-cirrhotic portal hypertension 2
• Operative mortality of 11-17% in elective settings 5

Critical Pitfalls to Avoid

• Inadequate splenic vein length leads to tension on anastomosis and early thrombosis; ensure at least 3-4 cm of mobilized vein 1
• Injury to pancreatic tail during dissection can cause postoperative pancreatitis or fistula 2
• Kinking or twisting of the anastomosis results in early shunt thrombosis 1
• Performing PSRS in patients with hepatofugal flow and significant ascites is contraindicated; these patients require total shunts 5