Liver resection (segmentectomy)

Why are we operating?

Removal of anatomical liver segments along Couinaud's planes: cancer surgery built on the fact that the liver is eight independent territories, each with its own inflow, outflow and duct.

Indication: Colorectal liver metastases, hepatocellular carcinoma in a non-cirrhotic or well-compensated liver, and symptomatic benign lesions.

The operation in 4 steps

1. 01Assessment and ultrasound

   The abdomen is staged for disease beyond the plan, the liver mobilised on its ligaments, and intraoperative ultrasound maps the lesion, the hepatic veins and the portal pedicles.

   Why: Couinaud's segments are invisible from the surface; the ultrasound is the map that turns a smooth brown organ into eight addressable territories and confirms the planned segments are the right ones.

2. 02Inflow control

   The pedicle feeding the target segments, portal vein branch, hepatic artery branch and duct, is controlled, and the ischaemic demarcation line appears on the surface.

   Why: The demarcation line is the liver drawing its own resection margin: the territory of the clamped pedicle declares itself, and the transection plane follows the line the anatomy has drawn.

3. 03Parenchymal transection

   The liver is divided along the demarcation plane with crush or energy techniques, structures crossing the plane clipped or tied, and the middle hepatic vein respected at the boundary.

   Why: The liver has no fascia to follow; the plane is held by discipline and the ultrasound. Every vessel crossing it belongs to somebody, controlled, not avulsed, is what separates a dry field from a transfusion.

4. 04The cut surface and drains

   The raw surface is checked for bile leak and bleeding, argon or sutures applied where needed, and a drain left against the surface in selected cases.

   Why: The two late enemies of liver surgery, bile leak and bleed, both declare themselves at this surface. Ten unglamorous minutes here decide whether the ward course is quiet.

Danger zones

• Common bile duct

  The structure every biliary operation is designed not to injure; misidentification is the field's defining catastrophe.

• Right hepatic artery

  Crosses the triangle aberrantly in about one in seven patients, hugging the cystic duct.

• Duct of Luschka

  A small subvesical duct in the liver bed; missed, it declares itself as a postoperative bile leak.

Anatomy you need

The liver with its biliary tree: each Couinaud segment has its own inflow pedicle, which is what makes segmentectomy possible.

What can go wrong

• Postoperative bleeding

  Tachycardia first, hypotension late; falling urine output; a distending abdomen or rising drain output.

• Bile leak

  Right upper quadrant pain, fever, and bilious drain output, or a patient who is simply failing to thrive after cholecystectomy.

• Intra-abdominal abscess

  Swinging fevers, malaise, and localized pain from day 5 onward, classically after perforated appendicitis.