What is the management of a patient with a retained bullet (BB) injury?

Management of Retained BB Projectile

Hemodynamically stable patients with retained BB projectiles can be safely managed non-operatively with close clinical monitoring and serial imaging, reserving surgical intervention only for those with hemorrhagic shock, hard signs of vascular injury, or evidence of organ damage. 1

Initial Assessment and Triage

Hemodynamic Evaluation

• Assess vital signs immediately: systolic blood pressure ≥90 mm Hg and heart rate 50-110 beats per minute defines hemodynamic stability 2
• Classify hemorrhage severity using ATLS criteria to guide resuscitation needs 2
• Perform FAST examination to detect hemopericardium, pneumothorax, or free intraperitoneal fluid, which have immediate management implications 3

Imaging Strategy

• Obtain trauma radiography series to identify the BB location, trajectory, and any associated injuries (pneumothorax, hemothorax, rib fractures) 3
• Proceed to CT with IV contrast for all hemodynamically stable patients to determine projectile trajectory and assess for occult organ injury 3
• Use radiodense markers at entry/exit wounds to aid trajectory determination on CT 3
• Consider multiphasic CTA if vascular injury is suspected to differentiate arterial from venous bleeding 3

Non-Operative Management (Preferred for Stable Patients)

Indications for Conservative Approach

• Hemodynamically stable patients without signs of ongoing bleeding or organ injury can be managed expectantly 1, 4
• Intramuscular BB projectiles are safe to leave in place with serial monitoring 4
• Soft tissue retained fragments without neurovascular compromise do not require removal 1

Monitoring Protocol

• Serial clinical examinations over 48 hours to detect delayed complications 1
• Serial hemoglobin measurements to identify occult bleeding 2
• Echocardiography if cardiac involvement is suspected to localize projectile and evaluate pericardium 4
• Follow-up imaging driven by clinical condition rather than routine protocols 3

Antibiotic Management

• Administer 48-72 hours of first-generation cephalosporin with or without aminoglycoside for high-velocity wounds 1, 2
• Add penicillin if gross contamination is present to cover Clostridium species 1, 2
• Note that infection rates are low (2-4%) in civilian BB injuries, but retained fragments increase this risk 1

Surgical Intervention (Mandatory Indications)

Immediate Operative Indications

• Hemorrhagic shock (Class III: BP decreased, HR >120; Class IV: BP decreased, HR >140) requires immediate surgical bleeding control 1, 2
• Hard signs of vascular injury mandate exploration regardless of imaging findings 1
• Peritoneal penetration with organ injury evidenced by free fluid, mesenteric stranding, bowel wall thickening, or contrast extravasation on CT 1

Cardiac Injuries

• Intracardiac BB projectiles require individualized assessment based on chamber versus myocardial location 5, 6, 4
• Intramuscular cardiac BBs can be managed non-operatively with echocardiographic confirmation 4
• Intrachamber projectiles warrant removal due to embolization risk, typically via sternotomy or minimally-invasive approach 5, 6
• Monitor for conduction abnormalities (interventricular conduction delay) which typically resolve spontaneously 4

Extremity Injuries

• Unstable fractures require operative stabilization 1, 2
• High-velocity wounds need aggressive surgical debridement due to radial tissue damage from kinetic energy transfer 1, 2

Critical Pitfalls to Avoid

• Do not assume trajectory from external wounds alone: BBs can travel unpredictably through tissue planes and embolize to distant locations 7, 8
• Do not discharge based on negative initial CT alone: serial examinations over 48 hours are essential to detect delayed complications 1
• Do not rely on clinical presentation: patients may be asymptomatic despite significant retained projectiles in critical locations 6, 7, 4
• Perform whole-body imaging liberally: routine chest/abdominal X-ray or CT should be obtained for all gunshot injuries regardless of apparent location 7
• Recognize BB variability: each projectile behaves differently due to tumbling, fragmentation, and cavitation potential 3, 8

Location-Specific Considerations

Genitourinary Tract

• Penetrating injuries generally do not require routine projectile removal 3
• Follow-up imaging is not required for minor injuries but should be performed for moderate-to-severe injuries within 48 hours 3

Thoracoabdominal Region

• CT sensitivity is 88% for detecting bowel injury in gunshot wounds, but clinical correlation remains essential 1
• Consider diagnostic laparoscopy in equivocal cases to reduce non-therapeutic laparotomy rates 3