Missile embolism

Background

• Also known as "bullet embolism"
• Occurs when a bullet or bullet fragment enters the bloodstream.
• Can be arterial (80%) or venous
• Usually a small-caliber, low velocity projectile.
  • For this reason, incidence higher in non-military setting due to predominance of lower velocity projectiles
  • Incidence = 1.1% in recent combat operations

Clinical Features

• Number of entry wounds do not match exit wounds
• Location of bullet not consistent with predicted trajectory
• Bullet within intravascular or cavity without evidence of adjacent direct tissue injury
• Fluoroscopy showing foreign body move within vascular cavity
• CXR showing blurred foreign body within cardiac silhouette

Differential Diagnosis

• Intrapericardial foreign body
• Systemic venous embolism
• Right heart and pulmonary artery embolism
• Pulmonary vein embolism
• Left heart embolism
• Coronary artery embolism
• Paradoxical embolus (due to patent foramen ovale)

Diagnosis

• Need to maintain high index of suspicion, obtain full body radiography when indicated
• TEE/TTE if intrathoracic
• Serial fluoroscopy, especially if intracardiac, but will not determine if buried in myocardium or free moving within cavity
• FAST exam as reasonable supplement

Management

• Controversial - not all need to be removed
• Refer to diagram / literature review references

Disposition

• Admit to trauma floor vs. ICU based on hemodynamic stability vs. risk of further embolism complication

See Also

• Gun shot wounds
• Blast injuries