Duodenal Trauma

Etiology

As with any trauma, injuries are generally categorized as blunt or penetrating. The majority of duodenal trauma is caused by penetrating mechanisms. Only 22.3% of injuries are due to blunt mechanisms, while 77.7% are due to the penetrating mechanism.[5] 

Among penetrating injuries, 81% are caused by gunshot wounds, and 19% are caused by stabbings. Most blunt injuries are due to motor vehicle collisions (85%).[1] Other blunt causes include falls and assault.

Epidemiology

In the United States, trauma is the fourth most common cause of death. Trauma is the leading cause of death between ages 1 and 44.[6] For every trauma death, 30-times as many are admitted to the hospital, and up to 300-times as many are seen in the emergency department. Trauma is generally more common in the young adult male population, although it is being seen with increasing frequency in the elderly populations with a higher risk of morbidity and mortality.[7] 

General risk factors associated with increased morbidity and mortality include low socioeconomic status, non-Caucasian race, medical comorbidities, and living in a trauma “desert” with no nearby level I or II trauma centers.[8]

The trauma of the duodenum is rare and accounts for only 3.7 to 5% of all patients with an abdominal injury.[9] As with most trauma, they are most common in young males. The proportion of males to females is 5 to 1.[1] 70% occur between the ages of 16 to 30.[1]

Pathophysiology

Penetrating trauma generally causes injury by three mechanisms: direct injury, cavitation, and the resulting shock wave.[10] The direct injury is caused by a tearing and crushing force through tissue along the trajectory of the projectile and its fragments. Gunshot wounds have an added dissipation of kinetic energy that can further propagate injury. Cavitation occurs when a projectile with high energy travels through tissues.[10] 

Energy from the projectile causes a radial stretching that forms a temporary cavity with increased damage. The higher the energy mechanism, the larger the temporary cavity, and the greater the damage. Finally, a shock wave is created by rapid changes in pressure and temperature from the projectile.[11] This shock wave further propagates through the tissue causing additional damage.

Blunt trauma can cause bowel injury by either a crushing force, shearing force, or bursting force.[12] Crushing forces cause direct compression of the bowel wall, resulting in injury. Shearing forces cause injury by tearing around a fixed attachment due to acceleration/deceleration. Bursting forces cause an acute increase in intraluminal pressure leading to rupture.

The most common site of duodenal injury is the second portion (36%). This is followed by the third portion (18%), the fourth portion (15%), and the first portion (13%).[1] Injury to multiple portions is seen in 18% of patients.

Due to the proximity of other critical structures, duodenal injury rarely occurs in isolation. The most common associated injury is to the liver (17%), followed by the colon (13%), pancreas (12%), other small bowel (11%), and stomach (9%).

History and Physical

The history and physical examination of a patient with duodenal injury are generally nonspecific. The trauma evaluation will always start with an effective primary survey, including airway, breathing, circulation, disability, and exposure. At this point, a secondary survey will be performed to include a head-to-toe injury inventory and examination. This secondary survey will also involve obtaining an “AMPLE” history, including allergies, medications, past medical history, last oral intake, and events leading to the presentation.

Physical examination in relation to possible duodenal trauma is primarily related to the abdomen. This abdominal examination starts with an inspection to evaluate for distention, seat-belt signs, ecchymosis, lacerations, penetrating wounds, and possible evisceration. With penetrating wounds, the number and location of wounds should be noted. Although the classic abdominal examination then proceeds into auscultation, this step has less benefit in the setting of acute abdominal trauma and is often not performed.[13] 

The next steps in examining the abdomen are percussion and palpation to evaluate for tympany and peritoneal signs.[13] Peritoneal signs include significant tenderness, rebound, guarding, and rigidity.

History largely relates to the events around the trauma, such as the mechanism of injury. Symptoms such as abdominal pain, pain radiating to the back, chest pain, nausea, vomiting, or hematemesis could all be related to injury of the duodenum.[14] Duodenal trauma has also been rarely associated with severe testicular pain and priapism caused by sympathetic stimulation along the gonadal vessels.[15]

Evaluation

As with any trauma, evaluation should begin with an efficient primary and secondary survey, concentrating on the airway, breathing, and circulation. The definitive diagnosis of duodenal trauma will require a particularly high level of suspicion. Given the retroperitoneal location, the physical exam is further limited in detecting these injuries.[4]

After abdominal trauma, any patient with peritonitis or evisceration should be immediately taken for an exploratory laparotomy. [16] Similarly, after penetrating abdominal trauma, the hemodynamically unstable patient should undergo exploratory laparotomy. However, these hemodynamically unstable patients should first have the abdomen confirmed as the source of instability before laparotomy. Modern management generally uses focused assessment with sonography for trauma (FAST) to identify free abdominal fluid.[17] 

Diagnostic peritoneal lavage (DPL) is an option but has been replaced mainly by the advent of FAST. A stable patient can be evaluated by computerized tomography (CT).[18] The use of diagnostic laparoscopy is evolving but may be considered in the hemodynamically stable patient after penetrating abdominal trauma, depending on the circumstances.[19] Duodenal injury is graded by the American Association for the Surgery of Trauma (AAST) Organ Injury Scale.[20]

Treatment / Management

The retroperitoneal location of the duodenum within the “surgical soul” can make access and adequate visualization particularly difficult. The majority of the duodenum, including D1, D2, and the proximal portion of D3, can be visualized by a Kocher maneuver.[21] 

The Kocher maneuver is performed by incising the posterolateral peritoneal attachments of the duodenum and then retracting the duodenum and pancreatic head medially.[22] The distal D3 and D4, however, are more challenging to access are require a right-sided medial visceral rotation, known as a Cattel-Braasch maneuver.[23] This is performed by first replicating the Kocher maneuver and then extending the incision along the right white line of Toldt to mobilize the ascending colon fully. The right-sided medial visceral rotation is then completed by extending the incision around the cecum and incising the posterior mesenteric attachments toward the ligament of Treitz. This maneuver will provide a panoramic view of the entire inframesocolic retroperitoneum, including the distal D3 and D4.

The management of duodenal trauma largely depends on the extent of injury and involvement of other associated structures. The majority of simple duodenal hematomas seen on CT can be managed non-operatively.[24] This generally consists of nothing by mouth and serial abdominal examinations. These hematomas can progress and cause luminal obstruction. Obstruction should be managed by nasogastric tube decompression with total parenteral nutrition until the swelling dissipates.[25] (B3)

An upper GI contrast study can be considered every 5 to 7 days to evaluate progression. Surgical evacuation may be necessary if the obstruction fails to resolve after 2 or 3 weeks.

If a duodenal hematoma is identified intraoperatively, a Kocher maneuver should be performed, and the duodenum should be thoroughly inspected for signs of perforation. Without any signs of perforation, these hematomas are mainly managed conservatively. Evacuation of the hematoma found intraoperatively is indicated if there is a high suspicion of full-thickness injury or if there is > 50% luminal narrowing.

Traumatic duodenal laceration or perforation requires surgical intervention. The preferred treatment for the majority of duodenal lacerations is through a primary repair.[26] Serosal tears and partial-thickness lacerations can be repaired in a Lembert fashion. It is estimated that primary repair is safe for about 70-85% of all traumatic duodenal injuries.[27] (B2)

Primary repair may even be considered in some cases of complete transection with simple duodenal duodenostomy, as opposed to other areas of the small bowel that would be managed by larger resection. A primary repair requires minimal tissue loss with no tension or involvement of the ampulla. The use of a nasogastric tube to allow temporary protection of the repair can also be considered. Extraluminal drainage is a topic of debate with no level I evidence to guide practice.

After primary repair, if the duodenal injury is severe (grade III-IV) or there is concomitant pancreatic injury, a pyloric exclusion should be considered to protect the repair.[28] Pyloric exclusion involves creating a gastrotomy, through which the pylorus is closed with absorbable sutures. Both polyglycolic acid (Vicryl) and polydioxanone (PDS) can be considered.[29] A gastrojejunostomy is then created using the same gastrostomy site. After 4 to 12 weeks, the sutures will absorb, and the pylorus will reopen.(B2)

If there is significant tissue loss putting the repair under tension, or if the injury involves the ampulla, a roux-en-Y duodenal-jejunostomy should be considered. For massive injuries involving the head of the pancreas, the patient may require a pancreaticoduodenectomy (Whipple procedure).[30] This, however, should never be done in an emergent setting. These patients should first have wide drainage at the initial operation, followed by the definitive pancreaticoduodenectomy upon medical stabilization.

There are other historical options to mention that have generally fallen out of favor. These include duodenal diverticularization and triple-ostomy repair. Duodenal diverticularization involves performing an antrectomy and gastrojejunostomy to permanently bypass the primary repair.[31] A tube duodenostomy can also be added for decompression to completely drain biliary fluid as well. Additionally, a lateral tube duodenostomy has been added with the goal of creating a controlled fistula to prevent the formation of an uncontrolled fistula. This approach, however, has been associated with unnecessarily high morbidity and has mostly been abandoned.

A triple-ostomy repair involves a primary repair followed by gastrostomy, duodenostomy, and jejunostomy.[32] This was an attempt to totally drain all fluid paths during the healing process while being able to feed the small bowel distal to the injury. A modified triple-tube repair uses a nasogastric tube with a feeding jejunostomy and retrograde jejunostomy tube instead.

Differential Diagnosis

The presentation of duodenal trauma is nonspecific, with many other etiologies presenting similarly. 

• Esophageal trauma
• Stomach trauma
• Small bowel (jejunum or ileum) trauma
• Colorectal trauma
• Mesenteric trauma
• Mesenteric hematoma
• Intraabdominal vascular trauma
• Pancreas trauma
• Liver trauma
• Spleen trauma
• Kidney trauma
• Bladder trauma

Prognosis

Duodenal trauma is associated with increased morbidity and mortality. An overall morbidity rate of 22 to 27% is seen. A mortality rate of 5 to 30% is reported but varies by grade and timing.[1] 

Mortality is reported to be 8.3% for grade I, 18.7% for grade II, 27.6% for grade III, 30.8% for grade IV, and 58.8% for grade V. Early deaths are generally due to exsanguination while late deaths are due to fistula, sepsis, and organ failure. One of the most consequential factors in predicting mortality is a delay in diagnosis. A delay in diagnosis by over 24 hours nearly quadruples the mortality rate.[33]

Complications

• Missed injury
• Intraabdominal abscess
• Duodenal fistula
• Duodenal obstruction
• Recurrent pancreatitis
• Bleeding