الفهرس 
SURGICAL ANATOMYOnly 14 pages are availabe for public view
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Abstract
Esophageal injuries are uncommon but can have tragic outcomes if not detected early and treated rapidly.
Classification of esophageal injury recognizes three major categories of causes: penetrating trauma, chemical trauma and foreign body ingestion injuries. Perforating trauma includes gunshot wounds, stab wounds, and medical instrumentation injuries from endoscopic procedures, blunt trauma occurs with crushing injuries and impact injuries, barotrauma caused by dramatic pressure changes within the esophagus. Chemical trauma include those from ingestion of a caustic material that causes injury to the entire esophagus. Foreign body ingestion may cause a laceration or puncture to the esophageal wall.
Iatrogenic esophageal perforation is the most common cause of perforation. It may result from esophageal instrumentation such as endoscopy and dilatation or surgical dissection around the esophagus in the course of other operation as abdominal vagotomy and hiatal hernia repair.
Thoracic esophagus is more likely to be injured than cervical esophagus especially its lower third and becomes more susceptible to be injured by underlying disease, as it becomes more fragile.
Perforation occurs either as immediate total breach of esophageal wall or as mucosal laceration that is followed by intramural hematoma or abscess with subsequent delayed rupture.
Disruption of esophageal wall exposes the mediastinal tissue to ongoing contamination, infection and mediastinitis may develop.
Clinical features include dyspnea, pain in the neck or chest, and subcutaneous emphysema, the possibility of esophageal perforation should be considered at once especially when a recent history of esophageal instrumentation is present. X-ray examinations and contrast studies are essential for diagnosis. Also, computed tomography and use of flexible esophagoscopy may play a considerable role in the diagnosis.
Controversy continues about treatment of esophageal perforation especially when treated late. Delay in the diagnosis and treatment significantly influences the outcome with mortality rates approximately doubling if treatment is delayed beyond 24 hours.
The line of treatment and the prognosis depend on status of the patient, the free interval between treatment and perforation the presence of underlying esophageal disease, the site and the cause of the perforation.
The treatment may be conservative in selected cases of recent perforation, contained perforation and stable haemodynamics. It depends on restriction of oral intake, haemodynamic stabilization, and administration of broad spectrum antibiotics.
Generally, esophageal perforation requires prompt surgical therapy after the diagnosis. The treatment is directed towards elimination of infection, elimination of distal obstruction, closure of perforation, drainage, antibiotic therapy and nutritional support.
Primary surgical repair, often with a tissue buttress, remains the treatment of choice in early diagnosed patients in absence of underlying esophageal disease.
But when the diagnosis is delayed or in the presence of underlying esophageal disease, the treatment is directed towards drainage, exclusion and diversion, esophagectomy or stenting.
Chemical burns of the esophagus result from the inges¬tion of caustic substances (strong acid or alkali). Alkalis produc liquefaction necrosis, which almost ensures deep penetration, whereas acids usually cause coagulation necrosis, which in part limits the depth of the injury.
The site of caustic injury of the esophagus may be located almost equally in any one of its anatomic subdivisions or may be widespread throughout. Normally, the greater period of contact is in the lower esophagus hence, more extensive injury usually occurs in this area.
The burn injury to the esophagus has been divided into three phases. Inflammation, edema, and necrosis occur dur¬ing the first few days. Sloughing of esophageal tissue with mucosal ulceration occur in the second phase which last 3 to 4 weeks. In the third phase, cicatrization and stric¬ture formation may progress for many weeks.
Acute caustic ingestion is an indication for hospitalization, stabilizing the patient and assessing the severity of the injury. Oral intake should be withheld and hypovolemia corrected. Careful observation for evidence of airway obstruction, Broad-spectrum antibiotics, corticosteroids may mask signs of sepsis and visceral perforation and is not recommended.
Treatment can be conservative for mild cases with first degree burn, second and third degree burns usually requires surgical resection of severely damaged organs, usually a transhiatal esophagogastrectomy is the preferred choice.
Cases presenting later, usually have esophageal stricture, are managed by serial sets of dilatation or, if failed, surgical excision through a transhiatal approach with esophageal substitution done by transverse colon or better by gastric conduit.
A variety of objects and materials were inappropriately ingested, especially by children, by mentally disturbed or deranged persons. Many such objects pass into the stomach; others lodge in the esophagus and require removal by endoscopic manipulation.
Rarely surgery is indicated to remove impacted foreign body by esophagotomy and direct removal through cervical incision if in the neck whereas in the chest, either a posterior mediastinotomy or a thoracotomy approach is indicated.
In some instances, sharp or jagged foreign bodies lacerate the wall partially or completely. Most often such laceration occurs in the cervi¬cal esophagus but any point of normal narrowing in the tho¬racic esophagus or at a diseased area may be the site of perforation.