Three Hours of Follow-Up Is Sufficient for Asymptomatic Penetrating Thoracic Trauma

Penetrating thoracic trauma is termed “asymptomatic” if the patient has no symptoms, signs, or radiographic findings of intrathoracic injury, but delayed pneumothorax or hemothorax occurs in about 3% of such patients and usually necessitates tube thoracostomy. Patients with asymptomatic thoracic penetrating trauma usually are observed and undergo repeat chest radiography after 6 hours. However, findings from two studies suggest that 3 hours is sufficient for follow-up (JW Emerg Med May 16 2001 and Surg Gynecol Obstet 1992; 175:249).

In a prospective study, researchers compared chest radiography findings at 3 and 6 hours after presentation in patients who presented to a single emergency department within 2 hours after asymptomatic penetrating thoracic trauma (anatomic boundaries of injury: clavicles and base of the neck, superiorly; inferior costal margin and iliac crests, inferiorly). Supine anteroposterior chest radiographs were obtained at presentation, and upright posterioanterior and lateral chest radiographs were obtained at 3 and 6 hours. Patients with worrisome clinical or laboratory findings or findings of pneumothorax or hemothorax on the initial radiograph were excluded.

Of 100 patients who met inclusion criteria, 75% were men, 75% had stab wounds, and 25% had gunshot wounds. The average ED stay was 8.8 hours. Two patients had findings of pneumothorax on the 3-hour film; both patients underwent tube thoracostomy. No new cases of pneumothorax or hemothorax were detected on the 6-hour films. Patient charges, including the cost of radiographs and continuous pulse oximetry monitoring, were US$2802 for the 3-hour observation period and $4521 for the 6-hour period.