What is the workup and management for ingestion of a metal piece?

Management of Metal Foreign Body Ingestion

Endoscopy is recommended as first-line treatment for persistent esophageal foreign bodies, with timing based on the type of object and clinical presentation. 1

Initial Assessment and Diagnostic Workup

Clinical Evaluation

• Assess for symptoms: dysphagia, odynophagia, inability to swallow saliva, retrosternal pain, foreign body sensation, vomiting, drooling
• Check for signs of complications: fever, cervical subcutaneous emphysema, neck tenderness
• Evaluate for respiratory symptoms: choking, stridor, dyspnea (indicating possible airway obstruction)

Laboratory Tests

• Complete blood count (CBC)
• C-reactive protein (CRP)
• Blood gas analysis for base excess and lactate 1

Imaging

1. Plain Radiographs:

   • Obtain neck, chest, and abdominal radiographs to assess presence, location, size, shape, and number of metal objects
   • Include biplanar radiography with lateral projection to differentiate between tracheobronchial and esophageal foreign bodies
   • Note: Plain radiography has up to 47% false-negative rate for radiopaque objects 1

2. CT Scan:

   • Perform CT scan if perforation or other complications are suspected
   • Essential when plain radiographs are negative but clinical suspicion remains high
   • Sensitivity of 90-100% and specificity of 93.7-100% 1

3. Avoid Contrast Studies:

   • Contrast swallow is not recommended as it may coat the foreign body and impair endoscopic visualization
   • Risk of aspiration in patients with complete esophageal obstruction 1

Management Algorithm

Timing of Endoscopic Intervention

1. Emergent Endoscopy (within 2-6 hours):

   • Sharp-pointed metal objects (high risk of perforation, up to 35%)
   • Batteries
   • Magnets
   • Objects causing complete esophageal obstruction 1

2. Urgent Endoscopy (within 24 hours):

   • Other esophageal foreign bodies without complete obstruction 1

3. Observation:

   • 80-90% of ingested foreign bodies pass spontaneously through the GI tract
   • Consider observation for small, blunt metal objects that have passed into the stomach in asymptomatic patients 2

Endoscopic Techniques

• Flexible endoscopy: First-line approach for most foreign bodies
• Rigid endoscopy: Consider as second-line therapy, particularly for objects in upper esophagus 1
• Retrieval tools: Use baskets, snares, and grasping forceps for removal of sharp-pointed objects 1

Special Considerations

• Sharp objects: Require prompt removal due to high risk of perforation
• Magnets: Require urgent removal as they can attract each other across bowel walls causing pressure necrosis, perforation, and fistula formation 1, 3
• Batteries: Need immediate removal due to risk of electrical burns, pressure necrosis, and chemical injury 1

Post-Removal Management

• Evaluate for underlying esophageal disorders (present in up to 25% of cases)
  • Common conditions: esophageal stricture, hiatus hernia, esophageal web, Schatzki ring, eosinophilic esophagitis, achalasia, tumors 1
• Consider histological evaluation to rule out underlying pathology
• Monitor for complications: perforation, bleeding, infection

High-Risk Populations

• Patients with mental illness or intellectual disability require closer monitoring as they are at higher risk for foreign body ingestion 4, 3
• Patients with previous abdominal surgery (adhesions) or intestinal disease (Crohn's, stenosis) have higher risk of complications 2

Follow-up

• Clinical follow-up to ensure resolution of symptoms
• Repeat imaging if foreign body was not retrieved and has not passed naturally
• Psychiatric evaluation for patients with intentional ingestion 1

Complications to Monitor

• Perforation
• Obstruction
• Hemorrhage
• Abscess formation
• Fistula formation
• Stricture development (in cases with mucosal injury)

Remember that early intervention for sharp metal objects is crucial to prevent life-threatening complications such as perforation, which can lead to mediastinitis, peritonitis, or abscess formation.