Abdominal Trauma: Solid Organ & Hollow Viscus Injury

Evaluating blunt abdominal trauma

Stability is the branch point. After the primary survey, the decisive question is whether the patient is hemodynamically stable after initial resuscitation. Examination is unreliable with head injury, intoxication, or distracting injuries, so bedside ultrasound and CT fill the gap.

FAST. Focused assessment with sonography for trauma looks for free fluid in the pericardium, the hepatorenal space (Morison pouch, the most sensitive single view), the splenorenal recess, and the pelvis. It detects hemoperitoneum quickly but cannot grade organ injury and misses retroperitoneal (pancreas, duodenum, kidney) and hollow-viscus injuries.

Diagnostic peritoneal lavage. Largely replaced by FAST, DPL is positive with aspiration of ≥10 mL of gross blood or enteric contents, or lavage fluid with >100,000 RBC/mm³, >500 WBC/mm³, bacteria, bile, or food particles.

Penetrating abdominal trauma

Gunshot wounds. A bullet that enters the peritoneal cavity causes significant visceral or vascular injury in about 90% of cases, so transperitoneal gunshot wounds go to exploratory laparotomy, as does any penetrating wound with shock, peritonitis, or evisceration. Radiopaque markers on each wound plus plain films trace the trajectory: wounds plus retained bullets should total an even number. A few experienced centers observe carefully selected stable patients with tangential wounds, but the default is operation.

Anterior stab wounds. Only a minority need laparotomy. Operate for instability, peritonitis, evisceration, GI hemorrhage, or an impaled object. Otherwise, local wound exploration decides: intact anterior fascia means no peritoneal violation and allows discharge; fascial penetration leads to admission for serial examinations and blood counts over about 24 hours, with CT or diagnostic laparoscopy as adjuncts.

• Flank and back stab wounds: thick muscle hides retroperitoneal injury, so use CT with IV, oral, and rectal (triple) contrast.
• Left thoracoabdominal wounds: diagnostic laparoscopy to exclude an occult diaphragm tear.
• Evisceration: cover bowel or omentum with moist sterile dressings; do not push it back.
• Impaled objects: stabilize in place and remove only in the operating room, where the vessel it tamponades can be controlled.

Spleen and liver

Splenic injury. The spleen is the organ most often injured by blunt force. Clues are left upper quadrant pain, left lower rib fractures, and Kehr sign — left shoulder pain referred through the phrenic nerve (C3–C5) when blood irritates the diaphragm. Stable patients with injuries of any grade are managed nonoperatively: monitored bed, serial examinations and hemoglobin, and angioembolization for a contrast blush or pseudoaneurysm. Instability, peritonitis, or failed nonoperative care calls for splenectomy. Children's spleens are preserved whenever possible; nonoperative management succeeds in more than 90%.

An unstable patient with a known splenic injury goes to the operating room, not to CT or angiography.

After splenectomy. Asplenia carries a lifelong risk of overwhelming post-splenectomy infection, most often from Streptococcus pneumoniae, followed by Neisseria meningitidis and Haemophilus influenzae. Give pneumococcal, meningococcal (ACWY and B), and Hib vaccines — at least 2 weeks before an elective splenectomy or about 14 days after an emergency one — and teach patients to seek immediate care and antibiotics for any fever. In adults, a single dose of PCV20 or PCV21 covers pneumococcus, and MenACWY is a 2-dose primary series 8 weeks apart with a booster every 5 years. The smear shows Howell-Jolly bodies, and reactive thrombocytosis is common.

Liver injury. The liver is the organ most often hit by stab wounds and the second most often in blunt trauma, with right lower rib fractures as a clue. Stable patients, even with high-grade injuries, are managed nonoperatively, with angioembolization for active extravasation. In the unstable patient, the Pringle maneuver (clamping the hepatoduodenal ligament to occlude hepatic artery and portal vein inflow) slows bleeding, and perihepatic packing buys time. Bleeding that continues despite a Pringle maneuver comes from the hepatic veins or retrohepatic IVC, among the most lethal injuries in trauma.

Complications of nonoperative liver care. Bile leak or biloma (percutaneous drainage, ERCP with stent), abscess, delayed bleeding, and hemobilia — upper GI bleeding, right upper quadrant pain, and jaundice — which is treated with angioembolization.

Hollow viscus, duodenal, and pancreatic injury

Seat-belt sign. A transverse lap-belt bruise signals compression of bowel and mesentery against the spine and the flexion-distraction mechanism of a Chance fracture, a horizontal fracture through the vertebral body and posterior elements at the thoracolumbar junction or upper lumbar spine. The two injuries frequently coexist, especially in children.

Occult bowel injury. Early CT can look deceptively normal. Suspect bowel or mesenteric injury with free fluid but no solid-organ injury, bowel-wall thickening, mesenteric stranding or hematoma, or extraluminal air. Peritonitis may take hours to develop, so these patients are admitted for serial examinations, and peritonitis or free air mandates operation.

Duodenal hematoma. A focused epigastric blow — a bicycle handlebar, or abuse in a young child — crushes the duodenum against the spine. The intramural hematoma narrows the lumen, causing bilious vomiting and gastric outlet obstruction that may begin days later; a contrast study shows a coiled-spring pattern. Treatment is NG decompression and parenteral nutrition, and most hematomas resolve within 2–3 weeks; operate only for persistent obstruction or perforation. Duodenal perforation, by contrast, leaks air into the retroperitoneum and requires repair.

Pancreatic injury. The same mechanism can fracture the pancreas over the spine. Because the gland is retroperitoneal, FAST, early CT, and initial amylase and lipase may all be normal; persistent pain, rising enzymes, or new fluid collections warrant repeat CT plus MRCP or ERCP to assess the main pancreatic duct, the key determinant of management. Contusion with an intact duct is drained or observed; transection of the duct to the left of the superior mesenteric vessels is treated with distal pancreatectomy. Missed injuries present as pseudocyst, fistula, abscess, or pancreatitis.

Operative principles and abdominal compartment syndrome

Damage control. Hypothermia, acidosis, and coagulopathy (the lethal triad) feed one another. When a patient heads toward that spiral, the surgeon abbreviates the operation: control hemorrhage (packing, ligation), control contamination (staple off injured bowel without anastomosis), and leave the abdomen open under a temporary negative-pressure closure. Rewarming and correction of acidosis and coagulopathy continue in the ICU with balanced 1:1:1 blood product resuscitation, and the patient returns in 24–48 hours for definitive repair and closure.

Abdominal compartment syndrome. Massive resuscitation, bowel edema, retroperitoneal hematoma, packing, or closure under tension raise intra-abdominal pressure until organs fail. Pressure is measured through the bladder catheter (≤25 mL saline instilled, supine, at end-expiration). The tense abdomen compresses the renal veins and parenchyma (oliguria), elevates the diaphragm (rising peak airway pressures, hypercapnia), and reduces venous return (hypotension with a misleadingly high CVP); intracranial pressure can rise too.

Treatment. Decompressive laparotomy with a temporary closure is definitive and usually restores urine output and ventilation promptly. Sedation, neuromuscular blockade, NG and rectal decompression, and drainage of ascites only temporize. Prevention matters most: limit crystalloid, resuscitate with blood products, and leave the abdomen open after damage-control surgery.