Overview
Definition:
A Kehr T-tube is a flexible latex or silicone tube shaped like the letter "T", surgically placed into the common bile duct (CBD) primarily after CBD exploration or repair
Its purpose is to provide external drainage of bile, protect the suture line, and facilitate postoperative cholangiography to assess ductal patency and identify residual stones or leaks.
Epidemiology:
T-tubes are employed in a subset of patients undergoing biliary surgery, particularly those with choledocholithiasis, strictures, or suspected bile duct injuries
Their use has become less frequent with advancements in laparoscopic cholecystectomy and intraoperative cholangiography, but they remain crucial in specific complex cases.
Clinical Significance:
Proper management and timely removal of a Kehr T-tube are vital to prevent complications such as infection, bile leakage, cholangitis, and retained common bile duct stones
Understanding the protocol ensures optimal patient recovery and successful examination outcomes for DNB and NEET SS aspirants.
Indications For Placement
Primary Indications:
Management of common bile duct stones not amenable to clearance via ERCP
Repair of bile duct strictures or injuries
Decompression of the CBD after exploration
Prophylactic drainage in high-risk patients.
Secondary Indications:
Drainage of infected bile
Facilitating controlled drainage in cases of anastomotic leakage
Management of mirizzi syndrome where CBD clearance is challenging.
Contraindications:
Absolute contraindications are rare
Relative contraindications include severe coagulopathy, suspected distal obstruction not addressed by the tube, and active sepsis not controlled
Inability to secure adequate visualization during placement.
Postoperative Management
Tube Care:
The T-tube exit site should be kept clean and dry, dressed with sterile gauze
The drainage bag should be emptied regularly, and the volume and character of bile output meticulously recorded
Any changes in output (e.g., decreased volume, purulent discharge, bile stained effluent) require immediate attention.
Monitoring:
Close monitoring of vital signs is essential
Observe for signs of cholangitis (fever, jaundice, right upper quadrant pain), bile leak (bilious discharge from wound, ascites), pancreatitis, and pancreatitis
Laboratory parameters including CBC, LFTs, and electrolytes should be monitored regularly.
Fluid And Electrolyte Balance:
Bile loss can lead to dehydration and electrolyte imbalances, particularly hyponatremia and hypochloremia
Intravenous fluid resuscitation and electrolyte correction are often necessary
In some cases, a portion of the drained bile may be reintroduced enterally if it is clear and not infected.
Pain Management:
Postoperative pain should be managed with appropriate analgesics, typically opioids, with a gradual transition to oral agents as tolerated
Muscarinic side effects of opioids may be managed with laxatives.
T Tube Cholangiography
Timing And Technique:
Typically performed on postoperative day 5-7, or when adequate healing is anticipated
The procedure involves injecting a radio-opaque contrast medium gently through the T-tube, under fluoroscopic guidance
Films are taken in multiple projections.
Interpretation:
The cholangiogram assesses the patency of the common bile duct, the integrity of the anastomosis (if performed), and the presence of retained stones, strictures, or leaks
Normal findings include a smooth, patent CBD and hepatic ducts draining freely into the duodenum, with no extravasation.
Abnormal Findings:
Retained stones appear as filling defects
Strictures present as narrowing
Leaks manifest as extravasation of contrast outside the biliary tree
Non-opacification of a segment may indicate obstruction or artifact
Duodenal visualization indicates patency of the distal CBD.
Tube Removal Protocol
Criteria For Removal:
Successful cholangiogram demonstrating a patent CBD without retained stones or leaks
Absence of cholangitis or significant abdominal pain
Adequate bile output through the tube that is not excessive and without signs of obstruction
Normalization of LFTs.
Removal Technique:
The T-tube is usually removed by gentle traction after disconnecting it from the drainage system
A simple pull without anesthesia is typically sufficient
Sometimes, a small stitch at the skin level may require removal
After removal, the exit site is dressed with a sterile bandage.
Post Removal Care:
Patients are observed for signs of bile leak for 24-48 hours post-removal
A small amount of bile drainage from the exit site is not uncommon and usually seals spontaneously within a few days
If significant bile leak occurs, the T-tube may need to be reinserted or alternative management initiated.
Complications
Early Complications:
Cholangitis: Infection of the biliary tree, often due to retained stones or obstructed drainage
Bile leak: Extravasation of bile from the T-tube site or an inadequately sealed duct
Pancreatitis: Inflammation of the pancreas, potentially triggered by manipulation or retained stones
Hemorrhage: Bleeding from the T-tube tract.
Late Complications:
Retained common bile duct stones: Stones not identified or removed during initial surgery or cholangiography
Biliary stricture: Narrowing of the bile duct at the T-tube insertion site, leading to obstruction
Tube dislodgement: Accidental premature removal of the T-tube
Incisional hernia: At the T-tube exit site.
Prevention Strategies:
Meticulous surgical technique during T-tube insertion
Thorough intraoperative cholangiography and CBD exploration
Judicious use of T-tubes
Careful postoperative monitoring and prompt management of any deviations from normal
Ensuring complete clearance of CBD stones prior to T-tube removal.
Key Points
Exam Focus:
Indications for T-tube placement and removal
Interpretation of T-tube cholangiography findings (normal vs
abnormal)
Management of early and late complications
Key criteria for T-tube removal.
Clinical Pearls:
Always confirm adequate drainage and character of bile pre-cholangiography
Never inject contrast against significant resistance
this could indicate obstruction and risk of duct rupture
Reintroduce bile enterally only if it is clear and non-infected to prevent electrolyte imbalance
Monitor for subtle signs of cholangitis, especially in immunocompromised patients.
Common Mistakes:
Premature removal of the T-tube before adequate healing
Incomplete clearance of CBD stones leading to cholangitis post-removal
Aggressive contrast injection during cholangiography
Failing to adequately monitor for post-removal bile leaks or signs of cholangitis
Overlooking electrolyte derangements due to excessive bile loss.