What is the management approach for aluminium phosphide poisoning?

Management of Aluminum Phosphide Poisoning

Immediate Priorities and Decontamination

There is no specific antidote for aluminum phosphide (AlP) poisoning; aggressive supportive care with intensive monitoring is the cornerstone of management, as mortality ranges from 30-100% even with small ingestions. 1, 2, 3

• Rapid gastric decontamination should be performed immediately upon presentation, though the effectiveness diminishes rapidly as phosphine gas is released within minutes of contact with gastric moisture 2, 4
• Ensure proper ventilation of treatment areas as phosphine gas is highly toxic to healthcare providers 5
• Avoid physical restraints without adequate sedation as this worsens outcomes 5

Cardiovascular Support

Refractory hypotension and cardiac failure are the primary causes of death and require aggressive hemodynamic support. 2, 4

Inotropic and Vasopressor Support

• Initiate norepinephrine infusion for hypotension unresponsive to fluid resuscitation 4
• Administer crystalloid fluid supplementation while monitoring for fluid overload 4

Cardiac Arrhythmia Management

• Magnesium sulfate is recommended for ventricular arrhythmias and cardiac membrane stabilization 1, 3, 6
• Lidocaine should be used for ventricular arrhythmias 3
• Calcium gluconate (100-200 mg/kg/dose) via slow infusion with ECG monitoring can be given for life-threatening arrhythmias 7, 5
• Continuous cardiac monitoring is essential as ECG changes (ST elevation, T-wave inversions, atrial fibrillation) develop within hours 2, 6

Advanced Cardiac Support

• Consider veno-arterial ECMO for refractory cardiogenic shock in centers with capability, as successful outcomes have been reported with prolonged support (up to 16 days) 3
• Intra-aortic balloon pump may be considered in severe cases 1

Respiratory Management

• Intubate early for respiratory failure or decreased consciousness 2, 4
• Consider CPAP ventilation for patients with adequate consciousness and without contraindications 5
• Mechanical ventilation should be initiated promptly when respiratory failure develops 2

Metabolic and Renal Support

Metabolic Acidosis

• Severe metabolic acidosis is a hallmark of toxicity and requires aggressive correction 2, 3
• Sodium bicarbonate (1-2 mEq/kg IV push) can be administered for severe acidosis 7
• Monitor arterial blood gases frequently 2

Acute Kidney Injury

• Initiate continuous renal replacement therapy (CRRT) or hemodialysis for severe metabolic acidosis and acute kidney injury 3
• High-flux dialysis membranes are recommended for more effective clearance if aluminum toxicity is suspected 5
• CRRT may be required for extended periods (up to 24 days in severe cases) 3

Rhabdomyolysis

• Monitor serum creatinine kinase and potassium to detect rhabdomyolysis 5
• Treat with adequate hydration and urine alkalinization if myoglobinuria develops 5

Adjunctive Pharmacotherapy

Membrane stabilizers and cardioprotective agents may reduce mortality, though evidence is limited to case reports. 1

• Magnesium sulfate as a membrane stabilizer (dose and frequency vary in literature) 1, 6
• N-acetylcysteine for antioxidant support 1, 4
• Trimetazidine as a cardioprotective agent 1
• Thiamine, vitamin C, and hydrocortisone may have potential benefit 1

Aluminum Toxicity Management

• Measure serum aluminum levels if aluminum toxicity is suspected, particularly in dialysis-dependent patients 5
• For confirmed aluminum toxicity with levels >60μg/L but <200μg/L, administer deferoxamine (DFO) at 5 mg/kg 5
• Do NOT administer DFO if serum aluminum levels are >200μg/L due to risk of acute neurotoxicity; instead perform intensive dialysis with high-flux membranes 5
• If DFO is used, avoid intravenous iron to limit formation of feroxamine 5
• DFO therapy carries risk of fatal mucormycosis; use reduced dosing (5 mg/kg) with expanded intervals between treatments 5

Multi-Organ Monitoring

• Monitor hepatic function (AST, ALT) as hepatotoxicity develops rapidly 2
• Check coagulation studies (PT/INR) for hepatic synthetic dysfunction 2
• Serial ECGs to detect evolving cardiac injury 2, 6
• Cardiac troponin levels for myocardial injury 6

Critical Pitfalls to Avoid

• Do not delay supportive care waiting for confirmatory testing—clinical suspicion based on history and rapid progression of shock is sufficient 2, 4
• Do not use aluminum hydroxide as a phosphate binder for more than 1-2 days to avoid cumulative aluminum toxicity 7, 5
• Do not administer sodium bicarbonate and calcium through the same IV line 7
• Ingestion of as little as 150-500 mg (one tablet contains ~3 grams) can be fatal—all exposures require ICU-level care 1, 2

Disposition

• All suspected or confirmed AlP poisoning cases require immediate transfer to a tertiary care center with ECMO and CRRT capability given the potential for rapid progression to multiorgan failure 3
• ICU admission is mandatory for intensive monitoring and aggressive supportive care 2, 4