What is the classification and treatment of bile duct injuries, specifically using the Strasberg classification?

Bile Duct Injury Classification

Primary Classification Systems

The Strasberg classification is the most commonly used system for categorizing bile duct injuries, dividing injuries into five types (A through E) based on anatomical location and injury pattern, though the ATOM classification is now recommended as the most recent and complete system. 1, 2

Strasberg Classification Types

Type A Injuries:

• Bile leak from minor ducts still in continuity with the common bile duct (cystic duct stump or small ducts in the liver bed) 2
• Do not involve the main biliary tree and represent minor injuries without tissue loss 2
• Managed with endoscopic therapy (ERCP with biliary stenting) achieving 96% success rates 2, 3

Type B Injuries:

• Complete occlusion of part of the biliary tree, typically an aberrant right hepatic duct that has been divided and excluded from the main biliary drainage system 2
• Will appear normal on ERCP because the occluded segment doesn't communicate with the main biliary system 2
• May require conservative management for small segments, but larger segments require surgical reconstruction with hepaticojejunostomy to prevent progressive liver damage 2

Type C Injuries:

• Bile leak from aberrant right hepatic duct not in continuity with the common bile duct 4
• Treatment tailored according to injury specifics (conservative, selective hepaticojejunostomy, or hepatectomy) 4

Type D Injuries:

• Lateral injury to the extrahepatic bile duct, typically from excessive traction causing medial perforations without continuity loss 4
• Requires hepaticojejunostomy for injuries at the common hepatic duct level 4
• May require hepaticojejunostomy with neoconfluence construction for injuries at the confluence level 4

Type E Injuries (Major Injuries):

• Circumferential injuries to major bile ducts with tissue loss 2
• Further subdivided according to the Bismuth classification (E1-E5) based on the level of injury 2
• E1: Injury >2 cm from the hepatic confluence 1
• E2: Injury <2 cm from the hepatic confluence 1
• E3: Injury at the hepatic confluence with intact communication between right and left hepatic ducts 1
• E4: Injury destroying the hepatic confluence with loss of communication between right and left hepatic ducts 1
• E5: Injury involving aberrant right sectoral duct plus injury to the common hepatic duct 1

Alternative Classification Systems

ATOM Classification (Most Recent): The World Society of Emergency Surgery recommends the ATOM classification as the most recent and complete system, which integrates anatomical damage, time of detection, and mechanism of injury 1

Anatomical Components:

• Injuries categorized by main biliary duct (MBD) versus non-main biliary duct (NMBD) involvement 1
• Main biliary duct injuries classified by anatomical level (1-6) 1
• Each injury described as complete (C) or partial (P), with loss of substance (LS) noted when applicable 1
• Vasculobiliary injury (VBI) documented as present (VBI+) or absent (VBI-), with specific injured vessel noted (RHA, LHA, CHA, PV, MV) 1

Temporal Components:

• Early intraoperative (Ei) 1
• Early postoperative (Ep) 1
• Late (L) 1

Mechanism Components:

• Mechanical (Me): direct surgical trauma from instruments 1
• Energy driven (ED): thermal injury from electrocautery or other energy devices 1

Treatment Algorithm Based on Classification

Minor Injuries (Strasberg Type A)

• First-line: ERCP with biliary stenting achieving 96% success rate 2, 3
• Managed almost exclusively by endoscopists 3

Moderate Injuries (Strasberg Types B-D)

Type B:

• Small segments: Conservative management 2
• Larger segments: Hepaticojejunostomy to prevent progressive liver damage 2

Type D:

• Common hepatic duct injuries: Hepaticojejunostomy 4
• Confluence level injuries: Hepaticojejunostomy with neoconfluence construction 4
• Left hepatic duct injuries: Selective left hepaticojejunostomy 4

Major Injuries (Strasberg Type E)

Definitive treatment: Roux-en-Y hepaticojejunostomy is the treatment of choice, achieving 88-95% success rates when performed by experienced surgeons 1, 2, 3

Technical principles for hepaticojejunostomy:

• Remove clips and scar tissue from the proximal bile duct stump 1
• Establish adequate caliber anastomosis using narrow proximal bile duct with normal mucosa 1
• Use fine suture technique (5-0 or 6-0) according to bile duct wall thickness 1
• Follow principles of single-layer stitching, uniform margins, appropriate density, moderate knotting strength, and tension-free anastomosis 1

Timing of Repair

Intraoperative detection:

• Repair immediately ONLY if experienced biliary surgery specialists are available 5, 1, 6
• If specialist expertise unavailable, perform drainage and refer to specialist centers 5, 6

Early postoperative detection without inflammation:

• Primary repair can be performed 5, 6

Cases with infection, peritonitis, or vascular injury:

• Delayed repair is mandatory after controlling bile leakage and infection 5, 6
• Definitive repair performed 4-6 weeks after effective control of inflammation and infection 5, 1, 6
• This represents a change from older recommendations of waiting at least 3 months 5

Critical Pitfalls to Avoid

Fundamental principle: Anastomosis and reconstruction must use healthy, non-ischemic, non-inflamed, and non-scarred bile duct 6

• Many repair failures occur due to failure to follow this principle, particularly when ischemic boundaries are unclear 6
• Using scarred bile duct wall or surrounding tissue will inevitably lead to surgical failure 6

Avoid end-to-end anastomosis: Not recommended for major bile duct injuries with tissue loss or when clips have been placed on the ducts due to high risk of stricture formation 1

Vasculobiliary injuries: Complex vasculobiliary injuries should be delayed rather than attempted intraoperatively, even by expert hepatopancreatobiliary surgeons 1

Stenting duration: Outcomes are best in patients stented for more than 6 months 3