Classification
Bile duct injuries can be classified based on location as intrahepatic or extrahepatic bile duct injuries and based on cause into traumatic bile duct injuries and iatrogenic bile duct injuries, with the latter being the most common.
Traumatic Bile Duct Injuries
Traumatic bile duct injuries are rare and are often caused by traffic accidents, falls, crushing injuries, or stab wounds. Such injuries typically occur as part of complex injuries; for example, intrahepatic bile duct injuries are often associated with hepatic trauma, while extrahepatic bile duct injuries are frequently accompanied by injuries to the duodenum or pancreas.
Iatrogenic Bile Duct Injuries
Iatrogenic bile duct injuries result from medical interventions such as abdominal surgeries, interventional treatments, or puncture procedures. The majority occur during cholecystectomy, with a smaller proportion during bile duct exploration, subtotal gastrectomy, or hepatic resection. They may also arise in procedures involving the duodenum or pancreas. Ischemic bile duct injuries may occur following hepatic artery embolization or liver transplantation, while thermal injuries to the bile ducts may result from radiofrequency ablation for liver cancer. The most common site of bile duct injury during cholecystectomy is at the junction of the cystic duct and the common hepatic duct.
Etiology
Factors contributing to bile duct injuries during cholecystectomy include:
Anatomical Variations
Variations in bile duct anatomy, such as a short or absent cystic duct, an abnormal angle of convergence between the cystic duct and the common hepatic duct (e.g., parallel alignment), or abnormally high or low junctions, can increase the risk of injury. Other anomalies include the cystic duct joining the left or right hepatic duct, accessory ducts, or aberrant bile ducts.
Local Pathological Factors
Severe inflammation, adhesions, or scarring in the Calot's triangle can disturb the local anatomical structure and make dissection challenging. Conditions such as Mirizzi syndrome can further complicate the anatomy. These factors may lead to misidentification or misinterpretation of the biliary structures, resulting in injury.
Surgical Errors
Common surgical errors include mistaken ligation and transection of the common bile duct or common hepatic duct due to misidentifying them as the cystic duct. This is particularly likely during blind clamping for bleeding from the cystic artery. Excessive traction on the common bile duct during cystic duct ligation can also result in partial ligation or tearing of the duct wall, leading to stenosis.
Thermal Injury
Use of electrocautery for dissection or coagulation in the Calot's triangle or hepatic hilum can cause thermal damage to the bile duct wall.
Ischemic Injury
Excessive dissection around the bile duct may disrupt the peribiliary vascular plexus (PBVP), leading to ischemia and secondary bile duct stricture.
Other upper abdominal surgeries may also inadvertently injure bile ducts. For example, inadequate exposure of the structures at the first hepatic hilum during hepatic lobectomy may damage the preserved hepatic ducts. During subtotal gastrectomy, the distal common bile duct may be sutured inadvertently while closing the duodenal stump, resulting in biliary obstruction. Procedures such as radiofrequency or microwave ablation for liver cancer may induce thermal injury and inflammation due to the heat conduction effect, subsequently leading to delayed bile duct strictures.
Diagnosis
Timely intraoperative recognition of bile duct injuries is crucial. The main intraoperative indicators include:
- Leakage of bile observed during surgery.
- Two openings identified at the cystic duct site in the resected gallbladder specimen.
- Intraoperative cholangiography showing discontinuity, localized stricture, or extravasation of contrast from the bile ducts.
In the early postoperative period, the diagnosis should be considered if the following manifestations occur:
- Biliary peritonitis.
- Drainage of bile through the abdominal drain.
- Early-onset obstructive jaundice.
In cases where bile duct injury is delayed or occult, the following symptoms may appear weeks or months after surgery:
- Late-onset obstructive jaundice.
- Recurrent biliary infections.
- Fluid collection beneath or around the liver.
For suspected bile duct injuries, imaging studies such as ultrasound, CT, MRCP, or ERCP are necessary to confirm the diagnosis.
Management
The management of bile duct injuries depends on factors such as the timing and severity of the injury, the presence of inflammation in surrounding tissues, the patient’s overall condition, and particularly liver function. Proper initial treatment is especially important.
Intraoperative Management of Bile Duct Injuries
For small lacerations (<3 mm) or partial excision of the bile duct wall, repair is typically performed using direct suturing with 5-0 or 6-0 non-absorbable sutures, usually without the need for an internal stent.
For larger lacerations or transection injuries where the length of the bile duct defect is less than 2 cm, end-to-end bile duct anastomosis is typically performed, with placement of an internal stent through the anastomotic site for at least six months.
For extensive bile duct injuries, defects longer than 2 cm, or cases where end-to-end anastomosis is associated with high tension or ischemia, a Roux-en-Y hepaticojejunostomy is considered appropriate.
Postoperative Obstructive Jaundice Following Undetected Extraluminal Bile Duct Transection and Ligation
When bile duct transection and ligation occur intraoperatively but are not detected at the time, patients may develop obstructive jaundice following surgery. In such cases, surgical intervention after about three weeks is preferred to allow passive dilation of the bile ducts, facilitating reconstruction. The usual procedure is Roux-en-Y hepaticojejunostomy, with removal of unhealthy bile duct and scar tissue, bile duct reconstruction, and suturing with absorbable sutures, either continuously or interrupted. In cases where bile duct injury is accompanied by peritoneal infection, biliary peritonitis, or vascular injury, delayed repair is often necessary, with surgical timing generally chosen 4-6 weeks after effective control of local inflammation and infection.
Postoperative Bile Duct Strictures Leading to Recurrent Cholangitis and Jaundice
For bile duct strictures caused by extrahepatic bile duct injuries, surgery is usually required. This involves creating a large, tension-free, mucosa-to-mucosa anastomosis between the proximally dilated bile duct and the jejunum via a Roux-en-Y hepaticojejunostomy. Any stones proximal to the stricture are removed during the procedure. In select cases of bile duct strictures, endoscopic or percutaneous transhepatic balloon dilation may be used, combined with the placement of a biliary stent for 3-6 months.
Prevention
Iatrogenic bile duct injury is a serious complication in biliary surgery, with potentially severe and sometimes irreversible consequences, including recurrent biliary infections, biliary cirrhosis, liver failure, or the need for liver transplantation. Thus, prevention of iatrogenic bile duct injury is critically important. Preventive measures include the following:
Surgeons should maintain a strong sense of responsibility, approach each cholecystectomy with care, and remain vigilant regarding biliary anatomical variations and pathological factors.
A clear surgical field during operations is essential. The anatomical relationships between the cystic duct, common hepatic duct, and common bile duct should be confirmed before ligating or transecting the cystic duct.
Proper tension-free conditions of the cystic duct should be ensured during ligation, maintaining a distance of approximately 0.5 cm from the wall of the common bile duct.
Any abnormal bleeding from the cystic artery should be addressed only after clearly identifying the source of the bleeding before clamping or suturing. Blind clamping in a "blood pool" should be avoided to prevent bile duct injury.
For difficulties in anterograde cholecystectomy, conversion to retrograde cholecystectomy or partial cholecystectomy can be considered.
The use of electrocautery near bile ducts for hemostasis or tissue dissection should be avoided to reduce the risk of thermal injury.
Excessive dissection around bile ducts should be avoided to protect the peribiliary vascular plexus and prevent ischemic bile duct injury.
For laparoscopic cholecystectomy, if adequate exposure of Calot's triangle is not achieved, conversion to open surgery should be performed in a timely manner.