Chapter 18 Operative Exposure in Abdominal Trauma: Exposure of the Pancreas and Duodenum

This chapter will discuss surgical exposure of the duodenum, pancreas, and nearby vascular structures.

Learning Objectives

By the end of the ASSET course, participants should be able to do the following:

1. Demonstrate operative exposure of the head of the pancreas and the second and third portions of the duodenum with the Kocher maneuver.
2. Demonstrate operative exposure of the body of the pancreas in the lesser sac.
3. Demonstrate exposure of the fourth portion of the duodenum and the inferior border of the pancreas by mobilizing the ligament of Treitz.
4. Demonstrate exposure of the distal pancreas using the Aird maneuver.
5. Discuss the management of injuries to body of the pancreas.
6. Identify the anatomic relationships of the duodenum, pancreas, and surrounding structures.

Considerations

• The duodenum is nestled among a number of vital structures, including the aorta, inferior vena cava (IVC), hepatic portal structures, renal arteries and veins, pancreas, and superior mesenteric artery and vein (Figure 1).
• Injuries to the pancreas and duodenum are often accompanied by life-threatening vascular injuries.
• Complex repairs to the duodenum or pancreas should rarely be undertaken at the initial operation if the patient has multiple concurrent injuries and is physiologically compromised. In these circumstances, it is best to use damage control techniques (hemorrhage and contamination control) with wide drainage of the pancreas.

• Definitive surgical intervention is best accomplished with the involvement of surgeons with appropriate expertise in these rare injuries.
• Complete assessment of the pancreas and duodenum requires several different operative maneuvers.
• A generous midline incision as part of a trauma laparotomy is used to access these structures. As with all trauma laparotomies, the patient should be prepped to the knees in case a segment of saphenous vein needs to be harvested for interposition arterial grafting.

Operative Technique to Expose the Anterior Pancreas

• The anterior segment of the pancreas is best accessed by entry into the lesser sac via division of the gastrocolic ligament.
• This tissue is divided inferior to the gastroepiploic vessels, between the stomach and the transverse colon, with cautery and/or division between clamps with ligation.
• As this dissection is carried to the patient’s right, care must be taken to avoid injury to the gastroepiploic arcade, as the gastrocolic connection may be foreshortened.
• With the stomach retracted cephalad, the anterior surface of the pancreas is identified at the base of the lesser sac (Figure 2).
• If a hematoma overlies the pancreas, it may be contained by the posterior peritoneum, which should be entered to fully explore the extent of the injury (Figure 3).

Operative Technique to Expose the Head of the Pancreas and Segments Two and Three of the Duodenum

• The anterior and medial surfaces of the duodenum are inspected by following the anterior surface of the stomach to the pylorus and tracing it around the second and third portions of the duodenum.
• The Kocher maneuver, with or without formal medial visceral rotation (chapter 15), exposes the lateral and posterior aspects of segments two and three of the duodenum (Figures 4 and 5), the head of the pancreas, the uncinate process, and the right renal pedicle.
• A right-to-left medial visceral rotation (chapter 15), which includes an extended Kocher maneuver, allows for inspection of the head and uncinate process of the pancreas, the entire duodenum, the IVC down to the pelvic brim, and the right kidney. With medial and superior rotation of the ascending colon and hepatic flexure, care must be taken to identify and avoid injury to the middle colic and superior mesenteric vessels (Figure 6).

Operative Technique to Expose the Posterior Pancreas and Fourth Portion of the Duodenum

• The fourth portion of the duodenum is inspected at the ligament of Treitz to the right of the inferior mesenteric vein at the base of the transverse mesocolon. The ligament may be taken down, as shown in Figure 7.
• The inferior border of the pancreas and posterior portion of the fourth segment should be carefully inspected by dividing the posterior peritoneum along the inferior aspect of the body of the pancreas and by dividing the ligament of Treitz.
• Mobilizing the duodenojejunal flexure allows exposure of the inferior aspect of the pancreas, as well as the aorta and the left renal pedicle (Figure 8). During mobilization, care must be taken to avoid injury to the inferior mesenteric vein.
• Again, the posterior aspects of the second and third duodenal segments can be visualized with the Kocher maneuver.

Operative Technique to Expose the Distal Pancreas (Aird Maneuver)

• The Aird maneuver involves dividing all peritoneal attachments to the spleen to allow medial mobilization of the spleen and tail of the pancreas (Figure 9).
• Lateral and inferior attachments of the pancreas should be divided sharply to the level of the inferior mesenteric vein to allow full medial rotation and improved exposure. The retroperitoneal attachments can be sharply dissected superiorly via the lesser sac.
• Mobilization of the spleen and tail of the pancreas allows inspection of the posterior tail of the pancreas and identification of the splenic vein and artery (Figure 10).
• Further exposure of the posterior pancreas is accomplished by dividing the retroperitoneal attachments along the inferior border, with retraction of the pancreas cephalad (Figure 11).
• With the spleen and tail of the pancreas mobilized, they can be rotated medially to completely inspect the body and tail of the pancreas (Figure 12).

Operative Technique to Expose the Portal Vein, SMV, and SMA

• The duodenum is exposed via a Kocher maneuver, and the lesser sac is entered to inspect the anterior portion of the pancreas.
• If active hemorrhage is present in the region of the neck of pancreas, there may be an injury to the portal vein, SMV, and/or SMA. After blunt dissection anterior to the SMV/portal vein and behind the neck of pancreas, a stapler may then be used to divide the neck. This allows for rapid exposure of injured vessel(s) and will help control any hemorrhage from the pancreas itself.
• The origin of the SMA can also be identified with a left-to-right medial visceral rotation (as described in chapter 15) or through the root of the small bowel mesentery.

Considerations for Pancreatic

Resection

• Resection proximal to the injury should occur if there is a definite (or strong suspicion of) pancreatic ductal injury.
• If the pancreas is disrupted to the left of the SMA/SMV, a distal pancreatectomy should be performed, with or without splenectomy (Figures 13 and 14).
• Splenic preservation is contraindicated if the patient has multiple injuries, is physiologically deranged (e.g., coagulopathic, hypothermic, acidotic), or has other time-sensitive injuries.
• If the injury is to the right of the SMA/SMV complex, a distal pancreatectomy may be required but will sacrifice the majority of the pancreatic mass (Figure 15). In the acute setting, it may be preferable to perform damage control drainage with delay of definitive resection.
• If there is massive injury to the head of the pancreas, the patient should be widely drained and resuscitated. Consideration should be given to performing one of several variations of the Whipple procedure once the patient is physiologically resuscitated.

Pearls and Pitfalls

The first priority is to control bleeding. Concurrent injuries may be managed with damage control techniques, with delayed reconstruction if necessary. External drainage, external drainage, external drainage ....

• The key for the majority of pancreatic injuries is to identify if there is a ductal injury; strong indicators include a more than 50 percent transected gland, a central injury, and massive tissue destruction.
• Consider options for early administration of postoperative enteral nutrition; intraoperative placement of feeding tubes is encouraged.