Benign biliary injuries are caused by surgical trauma in about 95% of cases. The remainder result from external abdominal trauma or, rarely, from erosion of the duct by a gallstone. Prevention of injury to the duct depends on a combination of technical skill, experience, and a thorough knowledge of the normal anatomy and its variations in the hilum of the liver. The number of bile duct injuries has risen sharply in the past few years along with the shift from open to laparoscopic cholecystectomy.
The most common lesion consists of excision of a segment of the common duct as a result of mistaking it for the cystic duct. Partial transection, occlusion with metal clips, injury to the right hepatic duct, and leakage from the cystic duct are other examples. A full discussion of how these injuries occur and how they can be prevented is beyond the scope of this text.
A clean incision of the duct without additional damage is best managed by opening the abdomen and suturing the incision with fine absorbable suture material.
Symptoms of Bile Duct Injuries and Strictures
Manifestations of injury to the duct may be evident in the postoperative period. Following laparoscopic surgery, bile ascites, manifested by abdominal distention, bloating, pain plus mild jaundice, is the usual presentation, since the duct is usually open to the abdomen. The symptoms are relatively mild and may for a time be thought to represent only ileus until a worsening picture requires further investigation.
Injuries following open cholecystectomy more often present with intermittent cholangitis or jaundice as a consequence of a biliary stricture. The first clear-cut symptoms may not be evident for weeks after surgery.
Findings are not distinctive. Bile ascites produces abdominal distention and ileus and, rarely, true bile peritonitis with toxicity. The right upper quadrant may be tender but usually is not. Jaundice is usually present during an attack of cholangitis.
The serum alkaline phosphatase concentration is elevated in cases of stricture. The serum bilirubin fluctuates in relation to symptoms but usually remains well below 10 mg/dL.
Blood cultures are usually positive during acute cholangitis.
Bile ascites can be suspected on ultrasound or CT scan. Fluid should be aspirated, and if it is bile, the diagnosis is clear. THC and ERCP are necessary to depict the anatomy. After laparoscopic cholecystectomy, the most common pattern is a blocked (by a metal clip) lower duct and an upper duct draining freely into the abdomen. With a stricture, the findings most often consist of focal narrowing of the common hepatic duct within 2 cm of the bifurcation and mild to moderate dilatation of the intrahepatic ducts.
Choledocholithiasis is the condition that most often must be differentiated from biliary stricture because the clinical and laboratory findings can be identical. A history of trauma to the duct would point toward stricture as the more likely diagnosis. The final distinction must often await radiologic or surgical findings. THC or ERCP should be definitive.
Other causes of cholestatic jaundice may have to be ruled out in some cases.
Complications develop quickly if the leak is not controlled. Bile peritonitis and abscesses may form. With stricture, persistent cholangitis may progress to multiple intrahepatic abscesses and a septic death.
Treatment of Bile Duct Injuries and Strictures
Bile duct injuries should be surgically repaired in all but a few patients who are likely to improve with a nonoperative approach. Excision of the damaged duct and Roux-en-Y hepaticojejunostomy is indicated for most injuries. The entire biliary tree must be outlined by cholangiograms preoperatively. The key to success is the thoroughness of the dissection and the ability ultimately to suture healthy duct to healthy bowel. This, in turn, depends on the experience with this particular operation.
When a definitive repair is technically impossible, the stricture may be dilated with a transhepatic balloon-tipped catheter. This is particularly applicable to patients with portal hypertension, whose hepatic hilum contains numerous venous collaterals that make operation hazardous.
The death rate from biliary injuries is about 5%, and severe illness is frequent. If the stricture is not repaired, episodic cholangitis and secondary liver disease are inevitable.
Surgical correction of the stricture should be successful in about 90% of cases. Experience at centers with an interest in this problem indicates that good results can be obtained even if several previous attempts did not relieve the obstruction. There is essentially no place for liver transplantation in this disease.