Emergency surgery is performed on a night club patron who has been stabbed and a large laceration in the liver is identified. In order to stop the bleeding the portal vein and hepatic artery can be clamped proximal to the porta hepatis where they:  pass anterior to the first part of the duodenum and head of pancreas  pass in the free edge of the lesser omentum  are retroperitoneal  are in contact with the anterior abdominal wall  are in contact with the posterior abdominal wall

The portal vein and hepatic artery are two major vessels that supply the liver. In the case of a liver laceration, clamping these vessels can help control bleeding. These vessels can be accessed at the porta hepatis, which is a deep fissure on the inferior surface of the liver where various structures, including the hepatic artery and portal vein, enter or leave the liver.

1. Pass anterior to the first part of the duodenum and head of pancreas: This statement is incorrect. The portal vein and hepatic artery do not pass anterior to the first part of the duodenum and head of pancreas. They are located in the hepatoduodenal ligament, which is a part of the lesser omentum.

2. Pass in the free edge of the lesser omentum: This statement is correct. The portal vein, hepatic artery, and common bile duct are all located within the free edge of the lesser omentum, which is a double layer of peritoneum that extends from the liver to the lesser curvature of the stomach and the first part of the duodenum.

3. Are retroperitoneal: This statement is incorrect. The portal vein and hepatic artery are not retroperitoneal. They are located within the peritoneum, specifically within the lesser omentum.

4. Are in contact with the anterior abdominal wall: This statement is incorrect. The portal vein and hepatic artery are not in direct contact with the anterior abdominal wall. They are located deep within the abdomen, within the lesser omentum.

5. Are in contact with the posterior abdominal wall: This statement is incorrect. The portal vein and hepatic artery are not in direct contact with the posterior abdominal wall. They are located within the lesser omentum, which is attached to the liver and stomach, not the posterior abdominal wall.