P3C270: The Wandering Pellet: An Unusual Presentation of an Air Gun Injury in a Child

Introduction: Over 13,400 children < 18 years old are treated yearly in emergency departments for injuries caused by non-powder guns. Bullet embolism is an unusual but serious complication of penetrating trauma. We present a rare case of pellet embolism to right femoral artery after an air gunshot chest injury in a child.

Case Description: A 6-year-old female presented to a tertiary center after she was accidentally shot in the chest with a BB gun by her brother. Child’s exam was reassuring, and she was hemodynamically stable, there were no other wounds noted on the remainder of the skin exam. Pelvic x-ray showed a metallic foreign body in the subcutaneous tissues overlying the right proximal femur (figure 1). The patient was then taken for a CTA of the chest, abdomen, and pelvis to rule out further intra-abdominothoracic injury given the unclear missile trajectory. Upon returning from CT, the patient was re-evaluated and observed to have a cold, pallid right lower extremity. A right dorsalis pedis pulse was now absent by palpation. While waiting for CT images to become available for review in the ED, a bedside point-of-care ultrasound was performed by the ED attending who identified a foreign body in the femoral artery with a lack of downstream arterial pulsatility by color flow (Figure 2). This was confirmed by the CT which showed small right hemopneumothorax and a metallic foreign body lodged in the right femoral canal. Child was transferred to a larger tertiary center with more robust pediatric surgery capabilities. Arteriotomy was performed which revealed the embolized metallic pellet and a thrombus in the superficial femoral artery. The pellet and thrombus were removed, and the artery was repaired. The patient recovered uneventfully in few days. At the 4-week outpatient follow-up appointment, she had made a full recovery.

Discussion: Non-powder firearms are a preventable and recurrent source of serious injuries to children. Penetrating wounds with low kinetic energy projectiles are more likely to pierce one vessel wall and not the other, leading the pellet to come to rest within the vessel lumen increasing risk for Embolic events. Our case is unusual in that the pellet embolization apparently occurred during the initial evaluation in the ED. The quick recognition of the embolism and expedited vascular intervention likely decreased the chances of long-term ischemic complications. We utilized bedside ultrasound as reliable tool to evaluate acute limb pulselessness in penetrating chest gunshot injury, excluding cardiac tamponade, significant pneumothorax, and localizing embolized pellet even before definitive confirmation with CT.

Conclusion: The embolic event should always be considered in any penetrating trauma without a plausible bullet trajectory or exit wound and negative initial localization on targeted radiographs. Serial physical exam and reevaluation should be done in any suspected pellet embolism.