Describe the clinical management of transmediastinal gunshot wounds

Describe the clinical management of transmediastinal gunshot wounds.

Injuries to internal organs caused by this type of trauma are unpredictable. Any organ, even outside of the thorax, may be injured depending on the path of the bullet. Penetrating trauma to the cardiac window, defined as a quadrangle bounded by the midclavicular lines laterally, the clavicles superiorly and 11th ribs inferiorly, is highly likely to damage the heart. Evaluation must include not only the heart but the other intrathoracic organs. Diagnostic algorithms for trans-mediastinal gunshot wounds suggest transferring unstable patients directly to the operating room. Stable patients may be evaluated by chest radiograph, pericardial ultrasound, and spiral CT. A patient with abnormal ultrasound findings should be transferred directly to the operating room. Patients with abnormal spiral CT findings may need further study with esophagram, angiogram, bronchoscopy, or esophago-scopy. Positive findings in any of these examinations requires surgery.

Patients with penetrating injury, and to a lesser extent with blunt injury, who require intubation and ventilation may develop systemic air embolism. This complication results from entry of higher-pressure alveolar air into injured lower-pressure pulmonary veins. Clinical signs and symp-toms of this frequently fatal complication include sudden cyanosis, hypotension or cardiac arrest, loss of consciousness, and air bubbles in the radial, retinal, or coronary arteries. Although surgical measures such as emergency thoracotomy and clamping of the hilum of the lacerated lung have been recommended, the immediate measure to minimize further embolism is to ventilate the patients with the lowest peak inspiratory pressure. Placement of a double-lumen tube or a bronchial blocker to isolate the injured lung, thus avoiding ventilation to the injured lung, is another measure when time and equipment become available.

Anesthetic management of these patients is challenging. The massive requirement of fluid and blood necessitates insertion of large-bore intravenous lines. Abnormal coagula-tion requires factor and platelet replacement. Airway management may be difficult because of airway injury or mediastinal shift from hematoma, often necessitating fiberoptic-guided technique to facilitate intubation or to avoid entry into a false passage. Acid–base and electrolyte balance should be maintained. Cardiac injuries must be repaired immediately, possibly requiring the availability of cardiopulmonary bypass for safe repair of major coronary artery injuries.