PRESENTATION: 4 ½ year FS German shepherd referred for surgical extraction of a tranquilizer dart entering the right side of the chest.

HISTORY: The patient had been hit by a car and was extremely agitated and aggressive, necessitating sedation to permit transport to an emergency clinic. The dart inadvertently entered the dog's chest.

PHYSICAL EXAMINATION: The dog was sedate on presentation. Vital signs were stable and there were multiple cutaneous lacerations from the car trauma. The dart entered the right cranial thoracic region.

DIAGNOSIS: Thoracic radiographs revealed the foreign body and pneumothorax.

TREATMENT: A right 7th thoracotomy was performed. The right middle lung lobe had been perforated and was removed. The point of the dart had perforated the mediastinum and esophagus. The dart was extracted and the esophageal lacerations were primarily sutured in a double layer interrupted pattern. The chest cavity was lavaged and a temporary thoracostomy tube was placed and maintained for 3 days postoperatively. Medications included injectable cephalosporin and aminoglycoside antibiotics, metoclopramide, cimetidine, and NPO for 24 hours followed by liquid diet.

OUTCOME: The dog was discharged 4 days postoperatively on oral medications with soft food diet and recovery was uncomplicated. There were no clinical signs of esophageal stricture noted up to 6 years postoperatively. Signs of stricture would have been expected by 1-5 weeks postoperatively.

DISCUSSION: The esophagus has no serosal layer and a segmental blood supply, which seem to impair healing compared to the rest of the gastrointestinal tract. Dehiscence and leakage are frequent complications of esophageal surgery which can lead to fatal mediastinitis. A double layer appositional simple interrupted closure provides the best immediate tissue strength and apposition, with improved healing. If esophageal closure must be performed very quickly in the compromised patient, simple interrupted appositional sutures are indicated.

Cimetidine is an H2 antagonist administered to decrease gastric acidity and subsequent mucosal damage if gastroesophageal reflux occurred. Ranitidine and omeprazole are more recently developed antacids that were not available at the time this case was managed. Metoclopramide reduces reflux by increasing lower esophageal sphincter pressure.

Temporary thoracostomy tubes are indicated if continued fluid or air production is considered possible postoperatively. Once there is no longer air production, and fluid production has stabilized to a minimal amount, tube removal is indicated. Presence of a thoracostomy tube itself can cause 2-4 ml/kg of fluid production per day.