What is the treatment for a patient with iron poisoning in the Intensive Care Unit (ICU)?

Treatment of Iron Poisoning in the ICU

Deferoxamine mesylate is the definitive treatment for acute iron poisoning in the ICU, administered intravenously at 15 mg/kg/hour continuously, with aggressive supportive care including fluid resuscitation, correction of metabolic acidosis, blood product replacement, and hemodynamic monitoring. 1, 2

Immediate Assessment and Stabilization

Critical Initial Interventions

• Secure airway, establish IV access, and initiate continuous hemodynamic monitoring with consideration of Swan-Ganz catheter placement for severe cases with shock or cardiac dysfunction 2
• Control shock with intravenous fluids, blood products, oxygen, and vasopressors as needed 1
• Correct metabolic acidosis with bicarbonate administration 1, 2
• Monitor for and manage coagulopathy with blood product replacement 2, 3

Key Clinical Parameters to Monitor

• Serum iron concentration (toxicity defined as >500 mcg/dL; survival reported with levels up to 16,706 mcg/dL with aggressive treatment) 2, 4
• Liver function tests (ALT/AST for hepatotoxicity) 5, 2
• Coagulation studies 2, 3
• Arterial blood gas for acidosis 1, 2
• Hemoglobin/hematocrit for gastrointestinal hemorrhage 3

Deferoxamine Administration Protocol

Dosing and Route

• Administer deferoxamine 15 mg/kg/hour as continuous IV infusion for patients with severe iron poisoning (serum iron >500 mcg/dL or significant systemic toxicity) 1, 4
• Alternative dosing schedule: 25 mg/kg/hour for 12 hours daily for 3 days has been used successfully in massive overdose 2
• Do NOT use intramuscular route in ICU patients with hemodynamic instability 1

Duration of Therapy

• Continue deferoxamine until serum iron normalizes, acidosis resolves, and patient is clinically stable 1, 3
• Typical duration is 24-48 hours, but may extend to 3-4 days in massive ingestions 2
• Monitor for vin rosé (rose-colored) urine indicating ferrioxamine excretion 3

Critical Pitfall: Hypotension Risk

• High-dose IV deferoxamine can cause acute hypotension additive to iron-induced shock 5
• Requires careful hemodynamic monitoring and may necessitate vasopressor support 2
• Consider macromolecular deferoxamine derivatives if available (deferoxamine-dextran or deferoxamine-hydroxyethyl starch), which do not cause hypotension 5

Supportive Care Measures

Cardiovascular Management

• Use Swan-Ganz catheter monitoring to guide management of iron-induced cardiac failure and shock 2
• Dopamine and nitroprusside therapy for cardiogenic shock 2
• Volume replacement for hypovolemic shock 1, 2

Respiratory Support

• Mechanical ventilation for adult respiratory distress syndrome (ARDS), which can be caused by both iron toxicity and deferoxamine therapy 2
• Monitor oxygen saturation continuously 1

Gastrointestinal Complications

• Do NOT use activated charcoal, cathartics, or oral complexing agents (bicarbonate, phosphate) as they are ineffective 6
• Gastric lavage only if presentation is within 1 hour and massive ingestion 1, 6
• Monitor for late gastrointestinal scarring and obstruction (may occur weeks later) 3

Hepatic Monitoring

• Serial liver function tests to detect hepatic necrosis 2, 3
• Coagulation factor replacement for liver failure-induced coagulopathy 2

Indications for Deferoxamine in ICU Setting

Initiate deferoxamine if ANY of the following are present:

• Serum iron concentration >500 mcg/dL 4
• Severe or persistent symptoms (altered mental status, hematemesis, bloody diarrhea, shock) 6, 3
• Metabolic acidosis 1, 2
• Coma or significant CNS depression 2
• Evidence of hepatotoxicity 5, 3

Therapies NOT Recommended

• Hemodialysis and exchange transfusion: Reserved only for rare cases where conservative therapy fails 3
• Surgical removal of tablets: Only indicated in exceptional circumstances with large numbers of visible tablets causing obstruction 3
• Phlebotomy: This is for chronic iron overload (hemochromatosis, transfusion-dependent anemia), NOT acute poisoning 7

Expected Complications in ICU

Early Phase (First 24-48 Hours)

• Hypovolemic and cardiogenic shock 2
• Metabolic acidosis 1, 2
• Gastrointestinal hemorrhage 3
• Coagulopathy 2

Intermediate Phase (Days 2-4)

• Hepatic failure 2, 3
• ARDS 2
• Persistent shock requiring vasopressor support 2

Late Sequelae (Weeks Later)

• Gastric outlet obstruction from scarring 2, 3
• Hepatic necrosis 3

Monitoring Response to Treatment

• Serial serum iron levels (should decline with chelation) 4
• Resolution of metabolic acidosis 1, 2
• Improvement in mental status 2
• Stabilization of hemodynamics 2
• Normalization of liver function tests 5
• Cessation of gastrointestinal bleeding 3