ALL Flashcards
What types of surgical portosystemic shunts are there?
Three categories:
1) non-selective shunts- eliminate hepatic portal perfusion.
2) selective shunts- decompress esophageal and gastric varices but have the potential to maintain portal perfusion.
3) partial shunts- incompletely decompress the entire venous system.
What are the classically described nonselective portosystemic shunts?
These procedures are largely relegated to history.
End to side portocaval shunt, side to side portocaval shunt and large diameter graft portocaval shunts. All associated with high operative mortality and profound encephalopathy. They were used largely to palliate variceal bleeding and intractable ascites in the past. Mostly in the era prior to liver transplantation.
What are the indications/contraindications to the only remaining selective shunt procedure - distal spleno-renal shunts? What is the basis of continued use?
The distal splenorenal shunt has been studied head to head with non-selective shunts and found to be equally impressive in decompressing esophageal and gastric varices with much less encephalopathy.
The procedure is mostly used in Child’s A &B alcoholic cirrhotics to control recurrent variceal bleeding not amenable to endoscopic means.
Medically intractable ascites is the main contraindication to the procedure as disruption of retroperitoneal lymphatics will worsen ascites.
What is the perioperative mortality and effect outcomes of the distal splenorenal shunt?
When performed electively in Child’s A & B cirrhotics, operative mortality is <10%. Post shunt encephalopathy is unusual. 5 year survival rates are 50-60%.
What partial shunt is still used in a few centers in the US and has excellent prospective data to support its use?
The small diameter H-type portocaval shunt. Using a small 8mm synthetic graft to offload the portal system, this procedure has similar to improved results as compared with distal splenorenal shunting.
Atleast in the few centers that employ this technique, the procedure can be extended to urgent and emergent indications and is technically simpler the splenorenal shunts.
In most institution, when endoscopic measures fail to resolve acute variceal bleeding, what is the next step in management?
TIPS- Tranjugular Intrahepatic Portosystemic shunts.
What are the indications for TIPS in cirrhotic patients?
Variceal bleeding when endoscopic & medical measures are exhausted, Intractable ascites, Hepatic Hydrothorax, Budd-Chiari syndrome, Hepatopulmonary syndrome.
In small series, it has been shown to be effective in hepatorenal syndrome.
The absolute contraindications to TIPS
1) Polycystic liver disease
2) CHF
3) Severe tricuspid regurgitation
4) Pulmonary HTN
The main relative contraindications are portal vein thrombosis, hepatic vein obstruction, encephalopathy. These make TIPS formation techniquely more difficult. Encephalopathy always worsens.
What are the primary complications of the TIPS procedure?
1) Shunt occlusion/stenosis - 10-15%
2) Encephalopathy - 10-45%
3) Stent malposition - 10-20%
4) Hemobilia - <5%
5) Sepsis
Most TIPS are plagued by recurrent thrombosis that is successfully lysed. However, this is a very resource intensive procedure in patients with poor longterm survival.
In a cirrhotic patient with ESLD who is otherwise eligible from a psychosocial and economic standpoint for liver transplantation. What is the primary determinant of priority for this scarce resource?
MELD score and anatomic characteristics of donor liver and recipient.
Portal hypertension and portal vein thrombosis are known to complicate orthotopic liver transplantation. What techniques/procedures can be employed to mitigate these technically difficult situations?
Veno-venous bypass and thromboendvenectomy if PVT is present.
What is the mainstay technique for endoscopic management of esophageal varices?
Variceal banding
Is there a role for peritoneovenous shunts for intractable ascites?
No. These procedures have essentially be abandoned except in rare cases do to their considerable complication profile. DIC, variceal bleeding, sepsis and SBO are well known to occur, but without demonstrated survival benefit.
What are the mainstays of treatment for ascites intractable to medical therapy (Salt restriction and diuretics)?
Large volume paracentesis followed by TIPS.
What is Budd-Chiari syndrome?
Hepatic venous outflow obstruction results in a rare form of portal hypertension. Most common etiology is Hepatic vein thrombosis
