portoenterostomy

Portoenterostomy, commonly called the Kasai procedure, is a pediatric surgical operation used to treat biliary atresia. The goal is to restore bile drainage from the liver into the intestine by removing obstructing fibrous tissue at the porta hepatis and connecting the liver’s residual ducts to a loop of small intestine, typically a Roux-en-Y jejunal limb. The procedure creates a direct conduit for bile to reach the gut, bypassing the obliterated extrahepatic biliary tree.

Indications and timing

Biliary atresia presents in neonates with cholestasis and jaundice. Portoenterostomy is the standard initial treatment for infants with probable extrahepatic biliary obstruction. Outcomes are best when the operation is performed early, ideally within the first two months of life; delayed diagnosis or surgery is associated with higher rates of persistent jaundice, progressive liver disease, and earlier need for liver transplantation. The procedure is not effective for other forms of neonatal cholestasis.

Technique

Following laparotomy, the surgeon exposes the porta hepatis, excises fibrous obstructive tissue, and creates a hepaticojejunostomy by attaching a loop of small intestine to the hepatic duct remnants. The aim is to establish mucosa-to-mucosa drainage from the liver into the intestinal lumen. A Roux-en-Y limb is commonly used. Postoperative care focuses on ensuring adequate drainage, preventing and monitoring for infection and cholangitis, and supporting nutrition. The exact technical details can vary by center.

Outcomes and prognosis

Many children experience initial bile drainage and improved growth, but long-term prognosis varies. A substantial proportion eventually develops progressive liver disease and may require liver transplantation. Survival with the native liver is improved when surgery is performed early, but overall transplant-free survival rates decline with age and severity of liver injury. Complications include cholangitis, portal hypertension, and cirrhosis.

History

The procedure is named after Morio Kasai, who described it in 1959. It remains the standard initial surgical approach for most infants with biliary atresia.