INCIDENCE

Gastric injuries usually result from penetrating trauma and occur in approximately 20% of gunshot wounds and 10% of stab wounds.^1–3 Blunt gastric trauma is much less common. The American Association for the Surgery of Trauma (East) multi-institutional study on hollow viscus injury reported that the prevalence of blunt gastric rupture was 0.06% in patients undergoing evaluation for blunt abdominal trauma and 2.1% of all patients found to have hollow viscus injury.⁴

MECHANISM OF INJURY

The stomach is at risk for injury after stab wounds to the left thoracoabdominal region of the body. A single perforation occurs in over 50% of these cases.² However, injury to adjacent organs is common. Gunshot wounds result in two or more gastric wounds in 90% of cases.² Although often associated with some surrounding tissue damage to the stomach, this is usually only significant with high-velocity missiles. Shotgun wounds at close range (<15 feet) are often associated with massive destruction of the abdominal wall, stomach, and other intra-abdominal organs.

Blunt injury to the stomach is most often the result of motor vehicle crashes, or motor vehicle–pedestrian trauma.^5–7 Less common causes include falls, assaults, and improperly performed cardiopulmonary resuscitation. Blunt gastric injuries include linear lacerations and complete gastric rupture. The postulated mechanisms for blunt gastric injury include sudden increases in intraluminal pressure resulting in a balloon-bursting type of phenomenon of a full stomach, compression against the spine (seat-belt injury), or a deceleration injury with shearing forces resulting in a laceration of the anterior stomach wall.

DIAGNOSIS

Gastric perforations caused by blunt forces are often large, and intraperitoneal contamination is usually significant. Peritoneal signs are usually obvious, leading to early surgical intervention. Patients with blunt gastric rupture are frequently in shock related to other significant injuries including spleen and/or liver wounds.

Patients with stab wounds and hypotension, peritonitis, or both should undergo laparotomy immediately. Asymptomatic patients without central nervous system injury (brain or spinal cord injury) or drug or alcohol involvement may be observed with repeated physical exams. In other patients, local wound exploration, diagnostic peritoneal lavage (DPL), or laparoscopy are alternatives. Laparoscopy is most helpful with thoracoabdominal stab wounds in identifying associated injuries to the diaphragm.⁸ Focused assessment with sonography for trauma (FAST) may not identify the small amount of fluid initially associated with hollow viscus injury, and thus may be misleading with isolated gastric injuries.

Early operation is indicated for symptomatic gunshot wounds to the abdomen. Occasionally, a tangential gunshot wound in a stable patient may be observed, or such a wound may be found after the patient undergoes either DPL or laparoscopy. Abdominal CT is also helpful in this situation. In patients suspected to have either blunt or penetrating gastric injury, the placement of a nasogastric tube is helpful. Not only does proper placement of a nasogastric tube minimize the risk of aspiration, but a bloody aspirate when present is highly suspicious for a gastric injury. In patients with blunt gastric injury and no obvious peritoneal signs, a supine film of the abdomen discloses free air in less than 50% of cases. In this situation, abdominal CT is more sensitive in identifying free air.

SURGICAL MANAGEMENT

The abdomen is explored through a midline incision. Visualization of the stomach is facilitated by nasogastric tube decompression. Control of hemorrhage is the first priority, followed by control of enteric spill. Gastric wounds may be rapidly initially controlled by a running locking full-thickness closure with absorbable sutures. A seromuscular layer of nonabsorbable sutures is placed later in the operation. This not only affords hemostasis, but also controls further peritoneal contamination by gastric contents. Alternatively a TA-stapler or Allis or Babcock clamp may be used for temporary control.

After attention to the more life-threatening injuries, the stomach wound may be addressed. The stomach should first be carefully inspected for ecchymosis or hematomas along either the lesser or greater curvature. Certain areas of the stomach are particularly difficult to assess: the gastroesophageal junction, high in the gastric fundus, the lesser curvature, and the posterior wall. Perixiphoid extension of the midline incision, the use of a self-retaining retractor, and positioning of the hemodynamically stable patient in the reverse Trendelenburg position may aid in exposure of these problematic areas. The gastroesophageal junction area may also be better exposed by division of the left triangular ligament and mobilization of the lateral segment of the left lobe. The posterior wall of the stomach is exposed by opening the gastrocolic ligament just outside the gastroepiploic arcade along the greater curvature of the stomach. Division of the short gastric vessels may be necessary to adequately expose the proximal gastric fundus. Occasionally, air insufflated into the stomach via the nasogastric tube with the stomach submerged in saline may help identify an occult injury to the stomach. Tangential wounds and/or single perforations of the stomach do occur, but this is a diagnosis of exclusion.

Gastric injuries thus identified are treated according to their severity (Table 1, Figure 1). Most intramural hematomas (grades I and II) are treated by careful evacuation, hemostasis, and closure with seromuscular sutures made of nonabsorbable material. Small grade I and II perforations can be closed in one or two layers. Because of the vascularity of the stomach, I prefer a two-layer closure after hemostasis is achieved.

Table 1 AAST Organ Injury Scale for Stomach

AAST, American Association for the Surgery of Trauma.

Modified from American Association for the Surgery of Trauma (AAST).

Figure 1 Algorithm for treatment of gastric injury.

Large (grade III) injuries near the greater curvature can be closed by the same technique or by the use of a GIA stapler. Certain defects may also be closed using a TA stapler. The staple line may be protected with a seromuscular closure using nonabsorbable sutures. Care must be taken to avoid stenosis in the gastroesophageal and pyloric area. A pyloric wound may be converted to a pyloroplasty to avoid possible stenosis in this area. Extensive wounds (grade IV) may be so destructive that a proximal or distal gastrectomy is required. Reconstruction with either a Billroth I or II anastomosis is dictated by the presence or absence of an associated duodenal injury. In rare cases, a total gastrectomy and a Roux-en-Y esophojejunostomy are necessary for severe injuries (grade V).

If a diaphragm injury occurs in association with a gastric perforation, contamination of pleural cavity with gastric contents can be problematic.⁹ Under most circumstances, it is sufficient to clear the pleural space through the diaphragmatic rent after closure of the gastric perforation. It may be necessary to enlarge the diaphragmatic injury to achieve complete evacuation of the pleural contamination. After surgical repair of the stomach, the diaphragm injury is closed, and a chest tube is placed. Occasionally, the contamination may be so severe, particularly if operation is delayed, that a separate thoracotomy to provide adequate drainage of the pleural space is necessary. Thoracoscopic evacuation of the gastric contamination of the pleural space followed by chest tube placement is another option.

MORTALITY

Mortality after gastric injury is related to the mechanism of injury and the presence of shock and transfusion requirements, as well as the number of associated injuries. The mortality associated with blunt gastric rupture has been reported to range from 0% to 66% and averages around 30%.^4–8 Associated intra- and extra-abdominal injuries are usually present. The intra-abdominal organs most frequently injured include the spleen, liver, small bowel, and pancreas. The most frequent extra-abdominal injuries include chest, extremity, and head. Hemorrhagic shock and complications related to the associated injuries account for the vast majority of deaths.

The overall mortality rate for penetrating gastric injuries is 14%–20%.^1–3 Early deaths are related to irreversible hemorrhagic shock from associated injuries. Mortality increases dramatically with the number of organs injured. The most common associated injuries include the liver, diaphragm, colon, lung, and small bowel. Injuries to the spleen, pancreas, and major blood vessels in the abdomen are also common. Mortality after either penetrating or blunt gastric injury rarely is the result of injury to the stomach. When it occurs, it is related to anastomotic dehiscence, abscess or fistula formation, and subsequent organ failure.

MORBIDITY

Major morbidity after gastric injury includes intra-abdominal abscess formation, bleeding, anastomotic breakdown, and empyema formation.^3,6 The severity of gastric injury and degree of contamination contribute to the development of intra-abdominal abscess formation. Intra-abdominal contamination is often significantly greater after blunt gastric injury.

After penetrating trauma, the incidence of intra-abdominal abscess formation and surgical site infection is similarly low for both isolated gastric and colonic injury. The low incidence of intra-abdominal abscess formation with either isolated stomach or colon injury increases dramatically when concomitant injuries to the liver, kidney, pancreas, or duodenum are present.^10,11 There is even a greater synergistic effect on intra-abdominal abscess formation with combined stomach and colon injuries. The risk of empyema increases significantly when there is a diaphragm injury in association with penetrating injuries to the stomach. Bleeding can occur from the surgical site or gastric suture line, and may require reoperation. Occasionally suture line bleeding may be controlled using endoscopic techniques. In the rare instances of gastric injuries that require resection and anastomosis, anastomotic stenosis may require revision.

CONCLUSION

Most gastric injuries require debridement and closure. On rare occurrences more complex procedures, including gastric resection and anastomosis, are required. Shock and associated injuries dictate overall outcome.